Merge remote-tracking branch 'origin/sl-firmware/rm-balance-safety-cutoffs'

# Conflicts:
#	esp32s3/balance/main/config.h

.gitea/workflows/ota-release.yml

@@ -0,0 +1,162 @@
+# .gitea/workflows/ota-release.yml
+# Gitea Actions — ESP32 OTA firmware build & release (bd-9kod)
+#
+# Triggers on signed release tags:
+#   esp32-balance/vX.Y.Z  →  builds esp32s3/balance/   (ESP32-S3 Balance board)
+#   esp32-io/vX.Y.Z       →  builds esp32s3-io/         (ESP32-S3 IO board)
+#
+# Uses the official espressif/idf Docker image for reproducible builds.
+# Attaches <app>_<version>.bin + <app>_<version>.sha256 to the Gitea release.
+# The ESP32 Balance OTA system fetches the .bin from the release asset URL.
+
+name: OTA release — build & attach firmware
+
+on:
+  push:
+    tags:
+      - "esp32-balance/v*"
+      - "esp32-io/v*"
+
+permissions:
+  contents: write
+
+jobs:
+  build-and-release:
+    name: Build ${{ github.ref_name }}
+    runs-on: ubuntu-latest
+    container:
+      image: espressif/idf:v5.2.2
+      options: --user root
+
+    steps:
+      # ── 1. Checkout ───────────────────────────────────────────────────────────
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      # ── 2. Resolve build target from tag ─────────────────────────────────────
+      # Tag format:  esp32-balance/v1.2.3  or  esp32-io/v1.2.3
+      - name: Resolve project from tag
+        id: proj
+        shell: bash
+        run: |
+          TAG="${GITHUB_REF_NAME}"
+          case "$TAG" in
+            esp32-balance/*)
+              DIR="esp32s3/balance"
+              APP="esp32s3_balance"
+              ;;
+            esp32-io/*)
+              DIR="esp32s3-io"
+              APP="esp32s3_io"
+              ;;
+            *)
+              echo "::error::Unrecognised tag prefix: ${TAG}"
+              exit 1
+              ;;
+          esac
+          VERSION="${TAG#*/}"
+          echo "dir=${DIR}"         >> "$GITHUB_OUTPUT"
+          echo "app=${APP}"         >> "$GITHUB_OUTPUT"
+          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
+          echo "tag=${TAG}"         >> "$GITHUB_OUTPUT"
+          echo "Build: ${APP} ${VERSION} from ${DIR}"
+
+      # ── 3. Build with ESP-IDF ─────────────────────────────────────────────────
+      - name: Build firmware (idf.py build)
+        shell: bash
+        run: |
+          . "${IDF_PATH}/export.sh"
+          cd "${{ steps.proj.outputs.dir }}"
+          idf.py build
+
+      # ── 4. Collect binary & generate checksum ────────────────────────────────
+      - name: Collect artifacts
+        id: art
+        shell: bash
+        run: |
+          APP="${{ steps.proj.outputs.app }}"
+          VER="${{ steps.proj.outputs.version }}"
+          BIN_SRC="${{ steps.proj.outputs.dir }}/build/${APP}.bin"
+          BIN_OUT="${APP}_${VER}.bin"
+          SHA_OUT="${APP}_${VER}.sha256"
+
+          cp "$BIN_SRC" "$BIN_OUT"
+          sha256sum "$BIN_OUT" > "$SHA_OUT"
+
+          echo "bin=${BIN_OUT}" >> "$GITHUB_OUTPUT"
+          echo "sha=${SHA_OUT}" >> "$GITHUB_OUTPUT"
+
+          echo "Binary:   ${BIN_OUT} ($(wc -c < "$BIN_OUT") bytes)"
+          echo "Checksum: $(cat "$SHA_OUT")"
+
+      # ── 5. Archive artifacts in CI workspace ─────────────────────────────────
+      - name: Upload build artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: firmware-${{ steps.proj.outputs.app }}-${{ steps.proj.outputs.version }}
+          path: |
+            ${{ steps.art.outputs.bin }}
+            ${{ steps.art.outputs.sha }}
+
+      # ── 6. Create Gitea release (if needed) & upload assets ──────────────────
+      # Uses GITHUB_TOKEN (auto-provided, contents:write from permissions block).
+      # URL-encodes the tag to handle the slash in esp32-balance/vX.Y.Z.
+      - name: Publish assets to Gitea release
+        shell: bash
+        env:
+          GITEA_URL: https://gitea.vayrette.com
+          TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          REPO: ${{ github.repository }}
+          TAG: ${{ steps.proj.outputs.tag }}
+          BIN: ${{ steps.art.outputs.bin }}
+          SHA: ${{ steps.art.outputs.sha }}
+        run: |
+          API="${GITEA_URL}/api/v1/repos/${REPO}"
+
+          # URL-encode the tag (slash in esp32-balance/vX.Y.Z must be escaped)
+          TAG_ENC=$(python3 -c "
+          import urllib.parse, sys
+          print(urllib.parse.quote(sys.argv[1], safe=''))
+          " "$TAG")
+
+          # Try to fetch an existing release for this tag
+          RELEASE=$(curl -sf \
+            -H "Authorization: token ${TOKEN}" \
+            "${API}/releases/tags/${TAG_ENC}") || true
+
+          # If no release yet, create it
+          if [ -z "$RELEASE" ]; then
+            echo "Creating release for tag: ${TAG}"
+            RELEASE=$(curl -sf \
+              -X POST \
+              -H "Authorization: token ${TOKEN}" \
+              -H "Content-Type: application/json" \
+              -d "$(python3 -c "
+          import json, sys
+          print(json.dumps({
+              'tag_name': sys.argv[1],
+              'name':     sys.argv[1],
+              'draft':    False,
+              'prerelease': False,
+          }))
+          " "$TAG")" \
+              "${API}/releases")
+          fi
+
+          RELEASE_ID=$(echo "$RELEASE" | python3 -c "
+          import sys, json; print(json.load(sys.stdin)['id'])
+          ")
+          echo "Release ID: ${RELEASE_ID}"
+
+          # Upload binary and checksum
+          for FILE in "$BIN" "$SHA"; do
+            FNAME=$(basename "$FILE")
+            echo "Uploading: ${FNAME}"
+            curl -sf \
+              -X POST \
+              -H "Authorization: token ${TOKEN}" \
+              -F "attachment=@${FILE}" \
+              "${API}/releases/${RELEASE_ID}/assets?name=${FNAME}"
+          done
+
+          echo "Published: ${BIN} + ${SHA} → release ${TAG}"

AUTONOMOUS_ARMING.md

@@ -7,7 +7,11 @@ The robot can now be armed and operated autonomously from the Jetson without req
 
 ### Jetson Autonomous Arming
 - Command: `A\n` (single byte 'A' followed by newline)
-- Sent via inter-board UART to the ESP32-S3 BALANCE firmware
+<<<<<<< HEAD
+- Sent via USB CDC to the ESP32 BALANCE firmware
+=======
+- Sent via USB Serial (CH343) to the ESP32-S3 firmware
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 - Robot arms after ARMING_HOLD_MS (~500ms) safety hold period
 - Works even when RC is not connected or not armed
 
@@ -42,11 +46,11 @@ The robot can now be armed and operated autonomously from the Jetson without req
 
 ## Command Protocol
 
-### Inter-board UART Protocol
-Communication uses 460800 baud UART with binary framing:
-`[0xAA][LEN][TYPE][PAYLOAD][CRC8]`
-
-### From Jetson to ESP32-S3 BALANCE (inter-board UART)
+<<<<<<< HEAD
+### From Jetson to ESP32 BALANCE (USB CDC)
+=======
+### From Jetson to ESP32-S3 (USB Serial (CH343))
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 ```
 A           — Request arm (triggers safety hold, then motors enable)
 D           — Request disarm (immediate motor stop)
@@ -56,7 +60,11 @@ H           — Heartbeat (refresh timeout timer, every 500ms)
 C<spd>,<str> — Drive command: speed, steer (also refreshes heartbeat)
 ```
 
-### From ESP32-S3 BALANCE to Jetson (inter-board UART)
+<<<<<<< HEAD
+### From ESP32 BALANCE to Jetson (USB CDC)
+=======
+### From ESP32-S3 to Jetson (USB Serial (CH343))
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 Motor commands are gated by `bal.state == BALANCE_ARMED`:
 - When ARMED: Motor commands sent every 20ms (50 Hz)
 - When DISARMED: Zero sent every 20ms (prevents ESC timeout)
@@ -137,4 +145,4 @@ When RC is disconnected:
 
 ## References
 - Issue #512: Remove ELRS arm requirement
-- Files: `esp32/balance/src/main.cpp` (arming logic), inter-board UART protocol (460800 baud, `[0xAA][LEN][TYPE][PAYLOAD][CRC8]`)
+- Files: `/src/main.c` (arming logic), `/lib/USB_CDC/src/usbd_cdc_if.c` (CDC commands)

CLAUDE.md

@@ -1,17 +1,36 @@
 # SaltyLab Firmware — Agent Playbook
 
 ## Project
-SAUL-TEE 4-wheel wagon robot: ESP32-S3 BALANCE (PID/CAN), ESP32-S3 IO (RC/sensors), Jetson Orin Nano Super (ROS2/SLAM).
+<<<<<<< HEAD
+**SAUL-TEE** — 4-wheel wagon (870×510×550 mm, 23 kg).
+Two ESP32-S3 boards + Jetson Orin via CAN. Full spec: `docs/SAUL-TEE-SYSTEM-REFERENCE.md`
+
+| Board | Role |
+|-------|------|
+| **ESP32-S3 BALANCE** | QMI8658 IMU, PID balance, CAN→VESC (L:68 / R:56), GC9A01 LCD (Waveshare Touch LCD 1.28) |
+| **ESP32-S3 IO** | TBS Crossfire RC, ELRS failover, BTS7960 motors, NFC/baro/ToF, WS2812 |
+| **Jetson Orin** | AI/SLAM, CANable2 USB→CAN, cmds 0x300–0x303, telemetry 0x400–0x401 |
+
+> **Legacy:** `src/` and `include/` = archived STM32 HAL — do not extend. New firmware in `esp32/`.
+=======
+Self-balancing two-wheeled robot: ESP32-S3 ESP32-S3 BALANCE, hoverboard hub motors, Jetson Orin Nano Super for AI/SLAM.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ## Team
 | Agent | Role | Focus |
 |-------|------|-------|
-| **sl-firmware** | Embedded Firmware Lead | ESP32-S3 firmware (Arduino/IDF), PlatformIO, CAN bus, inter-board UART protocol |
-| **sl-controls** | Control Systems Engineer | PID tuning, IMU sensor fusion, real-time control loops, safety systems |
+<<<<<<< HEAD
+| **sl-firmware** | Embedded Firmware Lead | ESP32-S3, ESP-IDF, QMI8658, CAN/UART protocol, BTS7960 |
+| **sl-controls** | Control Systems Engineer | PID tuning, IMU fusion, balance loop, safety |
 | **sl-perception** | Perception / SLAM Engineer | Jetson Orin, RealSense D435i, RPLIDAR, ROS2, Nav2 |
+=======
+| **sl-firmware** | Embedded Firmware Lead | ESP-IDF, USB Serial (CH343) debugging, SPI/UART, PlatformIO, DFU bootloader |
+| **sl-controls** | Control Systems Engineer | PID tuning, IMU sensor fusion, real-time control loops, safety systems |
+| **sl-perception** | Perception / SLAM Engineer | Jetson Orin Nano Super, RealSense D435i, RPLIDAR, ROS2, Nav2 |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ## Status
-USB CDC TX bug resolved (PR #10 — DCache MPU non-cacheable region + IWDG ordering fix).
+USB Serial (CH343) TX bug resolved (PR #10 — DCache MPU non-cacheable region + IWDG ordering fix).
 
 ## Repo Structure
 - `projects/saltybot/SALTYLAB.md` — Design doc
@@ -29,11 +48,11 @@ USB CDC TX bug resolved (PR #10 — DCache MPU non-cacheable region + IWDG order
 | `saltyrover-dev` | Integration — rover variant |
 | `saltytank` | Stable — tracked tank variant |
 | `saltytank-dev` | Integration — tank variant |
-| `main` | Shared code only (IMU drivers, USB CDC, balance core, safety) |
+| `main` | Shared code only (IMU drivers, USB Serial (CH343), balance core, safety) |
 
 ### Rules
 - Agents branch FROM `<variant>-dev` and PR back TO `<variant>-dev`
-- Shared/infrastructure code (IMU drivers, USB CDC, balance core, safety) goes in `main`
+- Shared/infrastructure code (IMU drivers, USB Serial (CH343), balance core, safety) goes in `main`
 - Variant-specific code (motor topology, kinematics, config) goes in variant branches
 - Stable branches get promoted from `-dev` after review and hardware testing
 - **Current SaltyLab team** works against `saltylab-dev`

TEAM.md

@@ -1,12 +1,22 @@
 # SaltyLab — Ideal Team
 
 ## Project
-SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S3 IO (RC/sensors), with Jetson Orin Nano Super for AI/SLAM.
+<<<<<<< HEAD
+**SAUL-TEE** — 4-wheel wagon (870×510×550 mm, 23 kg).
+Two ESP32-S3 boards (BALANCE + IO) + Jetson Orin. See `docs/SAUL-TEE-SYSTEM-REFERENCE.md`.
 
 ## Current Status
-- **Hardware:** Assembled — ESP32-S3 BALANCE + IO, VESCs, IMU, battery, RC all on hand
-- **Firmware:** Balance PID + VESC CAN protocol written, ESP32-S3 inter-board UART protocol active
-- **Status:** See current bead list for active issues
+- **Hardware:** ESP32-S3 BALANCE (Waveshare Touch LCD 1.28, CH343 USB) + ESP32-S3 IO (bare devkit, JTAG USB)
+- **Firmware:** ESP-IDF/PlatformIO target; legacy `src/` STM32 HAL archived
+- **Comms:** UART 460800 baud inter-board; CANable2 USB→CAN for Orin; CAN 500 kbps to VESCs (L:68 / R:56)
+=======
+Self-balancing two-wheeled robot using a drone ESP32-S3 BALANCE (ESP32-S3), hoverboard hub motors, and eventually a Jetson Orin Nano Super for AI/SLAM.
+
+## Current Status
+- **Hardware:** Assembled — FC, motors, ESC, IMU, battery, RC all on hand
+- **Firmware:** Balance PID + hoverboard ESC protocol written, but blocked by USB Serial (CH343) bug
+- **Blocker:** USB Serial (CH343) TX stops working when peripheral inits (SPI/UART/GPIO) are added alongside USB on ESP32-S3 — see `legacy/stm32/USB_CDC_BUG.md` for historical context
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ---
 
@@ -14,18 +24,30 @@ SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S
 
 ### 1. Embedded Firmware Engineer (Lead)
 **Must-have:**
-- ESP32-S3 firmware (Arduino / ESP-IDF framework)
-- PlatformIO toolchain
-- CAN bus protocol and VESC CAN integration
-- Inter-board UART protocol (460800 baud, binary framed)
-- Safety system design (tilt cutoff, watchdog, arming sequences)
+<<<<<<< HEAD
+- Deep ESP32 (Arduino/ESP-IDF) or STM32 HAL experience
+- USB OTG FS / CDC ACM debugging (TxState, endpoint management, DMA conflicts)
+- SPI + UART + USB coexistence on ESP32
+- PlatformIO or bare-metal ESP32 toolchain
+- DFU bootloader implementation
+=======
+- Deep ESP-IDF experience (ESP32-S3 specifically)
+- USB Serial (CH343) / UART debugging on ESP32-S3
+- SPI + UART + USB coexistence on ESP32-S3
+- ESP-IDF / Arduino-ESP32 toolchain
+- OTA firmware update implementation
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 **Nice-to-have:**
-- VESC firmware / VESC Tool experience
+- ESP32-S3 peripheral coexistence (SPI + UART + USB)
 - PID control loop tuning for balance robots
-- ELRS/CRSF RC protocol
+- FOC motor control (hoverboard ESC protocol)
 
-**Why:** Core firmware runs on ESP32-S3 BALANCE (PID/CAN master) and ESP32-S3 IO (RC/sensors). Need expertise in ESP32-S3 firmware and CAN bus integration with VESC motor controllers.
+<<<<<<< HEAD
+**Why:** The immediate blocker is a USB peripheral conflict. Need someone who's debugged STM32 USB issues before — ESP32 firmware for the balance loop and I/O needs to be written from scratch.
+=======
+**Why:** The immediate blocker is a USB peripheral conflict on ESP32-S3. Need someone who's debugged ESP32-S3 USB Serial (CH343) issues before — this is not a software logic bug, it's a hardware peripheral interaction issue.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ### 2. Control Systems / Robotics Engineer
 **Must-have:**
@@ -35,7 +57,7 @@ SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S
 - Safety system design (tilt cutoff, watchdog, arming sequences)
 
 **Nice-to-have:**
-- VESC motor controller experience
+- Hoverboard hub motor experience
 - ELRS/CRSF RC protocol
 - ROS2 integration
 
@@ -43,7 +65,7 @@ SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S
 
 ### 3. Perception / SLAM Engineer (Phase 2)
 **Must-have:**
-- Jetson Orin Nano Super / NVIDIA Jetson platform (JetPack 6)
+- Jetson Orin Nano Super / NVIDIA Jetson platform
 - Intel RealSense D435i depth camera
 - RPLIDAR integration
 - SLAM (ORB-SLAM3, RTAB-Map, or similar)
@@ -61,12 +83,13 @@ SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S
 ## Hardware Reference
 | Component | Details |
 |-----------|---------|
-| BALANCE MCU | ESP32-S3 BALANCE (Waveshare Touch LCD 1.28, QMI8658 IMU) |
-| IO MCU | ESP32-S3 IO (RC/sensors/LEDs board) |
-| Motors | 2x 8" pneumatic hub motors |
-| ESC Left | VESC left (CAN ID 68) |
-| ESC Right | VESC right (CAN ID 56) |
-| CAN Bridge | CANable 2.0 (Jetson USB → can0, 500 kbps) |
+<<<<<<< HEAD
+| FC | ESP32 BALANCE (ESP32RET6, MPU6000) |
+=======
+| FC | ESP32-S3 BALANCE (ESP32-S3RET6, QMI8658) |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+| Motors | 2x 8" pneumatic hoverboard hub motors |
+| ESC | Hoverboard ESC (EFeru FOC firmware) |
 | Battery | 36V pack |
 | RC | BetaFPV ELRS 2.4GHz TX + RX |
 | AI Brain | Jetson Orin Nano Super + Noctua fan |
@@ -77,4 +100,4 @@ SAUL-TEE 4-wheel wagon robot using ESP32-S3 BALANCE (PID/CAN master) and ESP32-S
 ## Repo
 - Gitea: https://gitea.vayrette.com/seb/saltylab-firmware
 - Design doc: `projects/saltybot/SALTYLAB.md`
-- Archived bug doc: `USB_CDC_BUG.md` (legacy STM32 era)
+- Bug doc: `legacy/stm32/USB_CDC_BUG.md` (archived — STM32 era)

cad/dimensions.scad

@@ -14,12 +14,11 @@ motor_axle_flat = 10;   // Flat-to-flat if D-shaft
 motor_body_dia = 200;   // ~8 inches
 motor_bolt_circle = 0;  // Axle-only mount (clamp style)
 
-// --- ESP32-S3 BALANCE board (Waveshare Touch LCD 1.28) ---
-// ⚠ Confirm hole positions before printing — verify in esp32/balance/src/config.h
-mcu_bal_board_w = 40.0;    // Waveshare Touch LCD 1.28 PCB approx width (TBD caliper)
-mcu_bal_board_d = 40.0;    // Waveshare Touch LCD 1.28 PCB approx depth (TBD caliper)
-mcu_bal_hole_dia = 3.2;    // M3 clearance
-mcu_standoff_h = 5;        // Standoff height
+// --- Drone FC (30.5mm standard) ---
+fc_hole_spacing = 25.5;  // GEP-F722 AIO v2 (not standard 30.5!)
+fc_hole_dia = 3.2;      // M3 clearance
+fc_board_size = 36;      // Typical FC PCB
+fc_standoff_h = 5;       // Rubber standoff height
 
 // --- Jetson Orin Nano Super ---
 jetson_w = 100;

chassis/ASSEMBLY.md

@@ -10,7 +10,7 @@
          ├─ bumper_bracket(front=+1) ──────────────────────┐
          │                                                  │
  ┌───────┴──────────── Main Deck (640×220×6mm Al) ─────────┴───────┐
- │  ← Jetson mount plate (rear/+X)   MCU mount (front/−X) →        │
+ │  ← Jetson mount plate (rear/+X)   FC mount (front/−X) →         │
  │          [Battery tray hanging below centre]                     │
  └───┬──────────────────────────────────────────────────────────┬───┘
      │                                                          │
@@ -56,21 +56,24 @@
 3. Fasten 4× M4×12 SHCS. Torque 2.5 N·m.
 4. Insert battery pack; route Velcro straps through slots and cinch.
 
-### 7  MCU mount (ESP32-S3 BALANCE + ESP32-S3 IO)
+<<<<<<< HEAD
+### 7  MCU mount (ESP32 BALANCE + ESP32 IO)
 
-> ⚠ Board hole patterns TBD — measure Waveshare Touch LCD 1.28 PCB with calipers and
-> update `FC_PITCH` / `FC_MOUNT_SPACING` in all scad files before machining the mount plate.
-> Reference: `docs/SAUL-TEE-SYSTEM-REFERENCE.md`.
+> ⚠️ **ARCHITECTURE CHANGE (2026-04-03):** ESP32 BALANCE retired. Two ESP32 boards replace it.
+> Board dimensions and hole patterns TBD — await spec from max before machining mount plate.
 
-1. Place silicone anti-vibration grommets onto M3 nylon standoffs.
-2. Lower ESP32-S3 BALANCE board onto standoffs; secure M3×6 BHCS — snug only.
-3. Mount ESP32-S3 IO board adjacent — exact layout TBD pending board dimensions.
-4. Orient USB-C connectors toward accessible side for field programming/debug.
+=======
+### 7  FC mount (ESP32-S3 BALANCE)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+1. Place silicone anti-vibration grommets onto nylon M3 standoffs.
+2. Lower ESP32 BALANCE board onto standoffs; secure with M3×6 BHCS. Snug only.
+3. Mount ESP32 IO board adjacent — exact placement TBD pending board dimensions.
+4. Orient USB connectors toward front of robot for cable access.
 
-### 8  Jetson Nano mount plate
+### 8  Jetson Orin Nano Super mount plate
 1. Press or thread M3 nylon standoffs (8mm) into plate holes.
 2. Bolt plate to deck: 4× M3×10 SHCS at deck corners.
-3. Set Jetson Nano B01 carrier onto plate standoffs; fasten M3×6 BHCS.
+3. Set Jetson Orin Nano Super B01 carrier onto plate standoffs; fasten M3×6 BHCS.
 
 ### 9  Bumper brackets
 1. Slide 22mm EMT conduit through saddle clamp openings.
@@ -92,8 +95,8 @@
 | Wheelbase (axle C/L to C/L) | 600 mm | ±1 mm |
 | Motor fork slot width | 24 mm | +0.5 / 0 |
 | Motor fork dropout depth | 60 mm | ±0.5 mm |
-| ESP32-S3 BALANCE hole pattern | TBD — caliper Waveshare board | ±0.2 mm |
-| ESP32-S3 IO hole pattern | TBD — caliper bare board | ±0.2 mm |
+| ESP32 BALANCE hole pattern | TBD — await spec from max | ±0.2 mm |
+| ESP32 IO hole pattern | TBD — await spec from max | ±0.2 mm |
 | Jetson hole pattern | 58 × 58 mm | ±0.2 mm |
 | Battery tray inner | 185 × 72 × 52 mm | +2 / 0 mm |
 

chassis/BOM.md

@@ -41,7 +41,11 @@ PR #7 (`chassis_frame.scad`) used placeholder values. The table below records th
 | 3 | Dropout clamp — upper | 2 | 8mm 6061-T6 Al | 90×70mm blank | D-cut bore; `RENDER="clamp_upper_2d"` |
 | 4 | Stem flange ring | 2 | 6mm Al or acrylic | Ø82mm disc | One above + one below plate; `RENDER="stem_flange_2d"` |
 | 5 | Vertical stem tube | 1 | 38.1mm OD × 1.5mm wall 6061-T6 Al | 1050mm length | 1.5" EMT conduit is a drop-in alternative |
-| 6 | MCU standoff M3×6mm nylon | 4 | Nylon | — | ESP32-S3 BALANCE / IO vibration isolation |
+<<<<<<< HEAD
+| 6 | MCU standoff M3×6mm nylon | 4 | Nylon | — | ESP32 BALANCE / IO board isolation (dimensions TBD) |
+=======
+| 6 | FC standoff M3×6mm nylon | 4 | Nylon | — | ESP32-S3 BALANCE vibration isolation |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | 7 | Ø4mm × 16mm alignment pin | 8 | Steel dowel | — | Dropout clamp-to-plate alignment |
 
 ### Battery Stem Clamp (`stem_battery_clamp.scad`) — Part B
@@ -69,8 +73,8 @@ PR #7 (`chassis_frame.scad`) used placeholder values. The table below records th
 | 9 | Motor fork bracket (L) | 1 | 8mm 6061 aluminium | **Update fork slot to Ø16.51mm before cutting** |
 | 10 | Motor fork bracket (R) | 1 | 8mm 6061 aluminium | Mirror of item 9 |
 | 11 | Battery tray | 1 | 3mm PETG FDM or 3mm aluminium fold | `chassis_frame.scad` — `battery_tray()` module |
-| 12 | MCU mount plate / standoffs | 1 set | PETG or nylon FDM | Includes 4× M3 nylon standoffs, 6mm height — hole pattern TBD |
-| 13 | Jetson Nano mount plate | 1 | 4mm 5052 aluminium or 4mm PETG FDM | B01 58×58mm hole pattern |
+| 12 | FC mount plate / standoffs | 1 set | PETG or nylon FDM | Includes 4× M3 nylon standoffs, 6mm height |
+| 13 | Jetson Orin Nano Super mount plate | 1 | 4mm 5052 aluminium or 4mm PETG FDM | B01 58×58mm hole pattern |
 | 14 | Front bumper bracket | 1 | 5mm PETG FDM | Saddle clamps for 22mm EMT conduit |
 | 15 | Rear bumper bracket | 1 | 5mm PETG FDM | Mirror of item 14 |
 
@@ -88,16 +92,23 @@ PR #7 (`chassis_frame.scad`) used placeholder values. The table below records th
 
 ## Electronics Mounts
 
-> ⚠ MCU board dimensions TBD — caliper Waveshare Touch LCD 1.28 and bare ESP32-S3 IO board
-> before machining mount holes. See `docs/SAUL-TEE-SYSTEM-REFERENCE.md`.
+> ⚠️ **ARCHITECTURE CHANGE (2026-04-03):** ESP32 BALANCE (ESP32) is retired.
+> Replaced by **ESP32 BALANCE** + **ESP32 IO**. Board dimensions and hole patterns TBD — await spec from max.
 
 | # | Part | Qty | Spec | Notes |
 |---|------|-----|------|-------|
-| 13 | ESP32-S3 BALANCE (Waveshare Touch LCD 1.28) | 1 | ~40×40mm PCB, hole pattern TBD | PID loop + CAN; USB-C toward accessible side |
-| 13b | ESP32-S3 IO (bare board) | 1 | TBD PCB size, hole pattern TBD | RC / motor / sensor I/O |
+<<<<<<< HEAD
+| 13 | ESP32 BALANCE board | 1 | TBD — mount pattern TBD | PID balance loop; replaces ESP32 BALANCE |
+| 13b | ESP32 IO board | 1 | TBD — mount pattern TBD | Motor/sensor/comms I/O |
 | 14 | Nylon M3 standoff 6mm | 4 | F/F nylon | ESP32 board isolation |
 | 15 | Anti-vibration grommet M3 | 4 | Ø6mm silicone | Under ESP32 mount pads |
-| 16 | Jetson Orin Nano Super | 1 | 69.6×45mm module + carrier | 58×58mm M3 carrier hole pattern |
+| 16 | Jetson Orin module | 1 | 69.6×45mm module + carrier | 58×58mm M3 carrier hole pattern |
+=======
+| 13 | ESP32-S3 ESP32-S3 BALANCE FC | 1 | 36×36mm PCB, 30.5×30.5mm M3 mount | Oriented USB-C port toward front |
+| 14 | Nylon M3 standoff 6mm | 4 | F/F nylon | FC vibration isolation |
+| 15 | Anti-vibration grommet M3 | 4 | Ø6mm silicone | Under FC mount pads |
+| 16 | Jetson Orin Nano Super B01 module | 1 | 69.6×45mm module + carrier | 58×58mm M3 carrier hole pattern |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | 17 | Nylon M3 standoff 8mm | 4 | F/F nylon | Jetson board standoffs |
 
 ---
@@ -148,8 +159,8 @@ Slide entire carousel up/down the stem with M6 collar bolts loosened. Tighten at
 | 26 | M6×60 SHCS  | 4  | ISO 4762, SS | Collar clamping bolts |
 | 27 | M6 hex nut  | 4  | ISO 4032, SS | Captured in collar pockets |
 | 28 | M6×12 set screw | 2 | ISO 4026, SS cup-point | Stem height lock (1 per collar half) |
-| 29 | M3×10 SHCS | 12 | ISO 4762, SS | FC mount + miscellaneous |
-| 30 | M3×6 BHCS  | 4  | ISO 4762, SS | FC board bolts |
+| 29 | M3×10 SHCS | 12 | ISO 4762, SS | ESP32 mount + miscellaneous |
+| 30 | M3×6 BHCS  | 4  | ISO 4762, SS | ESP32 board bolts (qty TBD pending board spec) |
 | 31 | Axle lock nut (match axle tip thread) | 4 | Flanged, confirm thread | 2 per motor |
 | 32 | Flat washer M5 | 32 | SS | |
 | 33 | Flat washer M4 | 32 | SS | |

chassis/chassis_frame.scad

@@ -8,9 +8,9 @@
 // Requirements:
 //   - 600mm wheelbase
 //   - 2x hoverboard hub motors (170mm OD)
-//   - ESP32-S3 BALANCE + IO board mounts (TBD hole pattern — see SAUL-TEE-SYSTEM-REFERENCE.md)
+//   - ESP32-S3 ESP32-S3 BALANCE FC mount (30.5x30.5mm pattern)
 //   - Battery tray (24V 4Ah — ~180x70x50mm pack)
-//   - Jetson Nano B01 mount plate (100x80mm, M3 holes)
+//   - Jetson Orin Nano Super B01 mount plate (100x80mm, M3 holes)
 //   - Front/rear bumper brackets
 // =============================================================================
 
@@ -37,9 +37,8 @@ MOTOR_FORK_H       = 80;    // mm, total height of motor fork bracket
 MOTOR_FORK_T       = 8;     // mm, fork plate thickness
 AXLE_HEIGHT        = 310;   // mm, axle CL above ground (motor radius + clearance)
 
-// ── MCU mount (ESP32-S3 BALANCE / IO boards) ─────────────────────────────────
-// ⚠ Hole pattern TBD — update before machining. See docs/SAUL-TEE-SYSTEM-REFERENCE.md
-FC_MOUNT_SPACING   = 0;     // TBD — set to actual ESP32-S3 board hole spacing
+// ── FC mount (ESP32-S3 BALANCE — 30.5 × 30.5 mm M3 pattern) ──────────────────────
+FC_MOUNT_SPACING   = 30.5;  // mm, hole pattern pitch
 FC_MOUNT_HOLE_D    = 3.2;   // mm, M3 clearance
 FC_STANDOFF_H      = 6;     // mm, standoff height
 FC_PAD_T           = 3;     // mm, mounting pad thickness
@@ -53,7 +52,7 @@ BATT_FLOOR         = 4;     // mm, tray floor thickness
 BATT_STRAP_W       = 20;    // mm, Velcro strap slot width
 BATT_STRAP_T       = 2;     // mm, strap slot depth
 
-// ── Jetson Nano B01 mount plate ──────────────────────────────────────────────
+// ── Jetson Orin Nano Super B01 mount plate ──────────────────────────────────────────────
 // B01 carrier board hole pattern: 58 x 58 mm M3 (inner) + corner pass-throughs
 JETSON_HOLE_PITCH  = 58;    // mm, M3 mounting hole pattern
 JETSON_HOLE_D      = 3.2;   // mm
@@ -211,7 +210,7 @@ module battery_tray() {
 
 // ─── FC mount holes helper ────────────────────────────────────────────────────
 module fc_mount_holes(z_offset=0, depth=10) {
-    // ESP32-S3 board M3 pattern, centred at origin — spacing TBD, update FC_MOUNT_SPACING
+    // ESP32-S3 BALANCE: 30.5×30.5 mm M3 pattern, centred at origin
     for (x = [-FC_MOUNT_SPACING/2, FC_MOUNT_SPACING/2])
     for (y = [-FC_MOUNT_SPACING/2, FC_MOUNT_SPACING/2])
         translate([x, y, z_offset])
@@ -248,7 +247,7 @@ module fc_mount_plate() {
     }
 }
 
-// ─── Jetson Nano B01 mount plate ─────────────────────────────────────────────
+// ─── Jetson Orin Nano Super B01 mount plate ─────────────────────────────────────────────
 // Positioned rear of deck, elevated on standoffs
 module jetson_mount_plate() {
     jet_x =  60;   // offset toward rear

chassis/ip54_BOM.md

@@ -104,8 +104,11 @@ IP54-rated enclosures and sensor housings for all-weather outdoor robot operatio
 | Component | Thermal strategy | Max junction | Enclosure budget |
 |-----------|-----------------|-------------|-----------------|
 | Jetson Orin NX | Al pad → lid → fan forced convection | 95 °C Tj | Target ≤ 60 °C case |
-| ESP32-S3 BALANCE | Passive; mounted on standoffs | 105 °C Tj | <70 °C ambient OK |
-| ESP32-S3 IO | Passive; mounted on standoffs | 105 °C Tj | <70 °C ambient OK |
+<<<<<<< HEAD
+| FC (ESP32 BALANCE) | Passive; FC has own EMI shield | 85 °C | <60 °C ambient OK |
+=======
+| FC (ESP32-S3 BALANCE) | Passive; FC has own EMI shield | 85 °C | <60 °C ambient OK |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | ESC × 2 | Al pad → lid | 100 °C Tj | Target ≤ 60 °C |
 | D435i | Passive; housing vent gap on rear cap | 45 °C surface | — |
 

chassis/prototype_baseplate.scad

@@ -65,11 +65,10 @@ CLAMP_ALIGN_D   =   4.1;   // Ø4 pin
 // D-cut bore clearance
 DCUT_CL         =  0.3;
 
-// MCU mount — ESP32-S3 BALANCE board (Waveshare Touch LCD 1.28)
-// ⚠ FC_PITCH TBD — update before machining. See docs/SAUL-TEE-SYSTEM-REFERENCE.md
-FC_PITCH        =  0.0;   // TBD — ESP32-S3 board hole spacing not yet confirmed
+// FC mount — ESP32-S3 BALANCE 30.5 × 30.5 mm M3
+FC_PITCH        = 30.5;
 FC_HOLE_D       =  3.2;
-// Board is offset toward front of plate (away from stem)
+// FC is offset toward front of plate (away from stem)
 FC_X_OFFSET     = -40.0;  // mm from plate centre (negative = front/motor side)
 
 // =============================================================================
@@ -203,7 +202,7 @@ module base_plate() {
                 translate([STEM_FLANGE_BC/2, 0, -1])
                     cylinder(d=M5, h=PLATE_THICK + 2);
 
-        // ── MCU mount (ESP32-S3 BALANCE — hole spacing TBD) ──────────────
+        // ── FC mount (ESP32-S3 BALANCE 30.5 × 30.5 M3) ────────────────────────
         for (x = [FC_X_OFFSET - FC_PITCH/2, FC_X_OFFSET + FC_PITCH/2])
         for (y = [-FC_PITCH/2, FC_PITCH/2])
             translate([x, y, -1])

chassis/rover_electronics_bay.scad

@@ -10,8 +10,8 @@
 //          • RPLIDAR A1M8 tower     — integrated on lid top
 //          • Ventilation slots      — all 4 walls + lid
 //
-// Shared mounting patterns:
-//   MCU   : TBD mm M3 (ESP32-S3 BALANCE / IO — see docs/SAUL-TEE-SYSTEM-REFERENCE.md)
+// Shared mounting patterns (swappable with SaltyLab):
+//   FC    : 30.5 × 30.5 mm M3 (ESP32-S3 BALANCE / Pixhawk)
 //   Jetson: 58 × 49 mm M3    (Orin NX / Nano Devkit carrier)
 //
 // Coordinate: bay centred at origin; Z=0 = deck top face.

chassis/saltyrover_chassis_r2.scad

@@ -16,8 +16,8 @@
 //   • D435i front bracket arm
 //   • Weight target: <2 kg frame (excl. motors/electronics)
 //
-// Shared patterns (swappable electronics):
-//   MCU   : TBD mm M3  (ESP32-S3 BALANCE / IO — see docs/SAUL-TEE-SYSTEM-REFERENCE.md)
+// Shared SaltyLab patterns (swappable electronics):
+//   FC  : 30.5 × 30.5 mm M3  (ESP32-S3 BALANCE / Pixhawk)
 //   Jetson: 58 × 49 mm M3    (Orin NX / Nano carrier board)
 //   Stem  : Ø25 mm bore      (sensor head unchanged)
 //
@@ -87,9 +87,9 @@ STEM_COLLAR_OD = 50.0;
 STEM_COLLAR_H  = 20.0;   // raised boss height above deck top
 STEM_FLANGE_BC = 40.0;   // 4× M4 bolt circle for stem adapter
 
-// ── MCU mount — ESP32-S3 BALANCE / IO boards ─────────────────────────────────
-// ⚠ FC_PITCH TBD — update before machining. See docs/SAUL-TEE-SYSTEM-REFERENCE.md
-FC_PITCH    =  0.0;  // TBD — ESP32-S3 board hole spacing
+// ── FC mount — ESP32-S3 BALANCE / Pixhawk (30.5 × 30.5 mm M3) ────────────────────
+// Shared with SaltyLab — swappable electronics
+FC_PITCH    = 30.5;
 FC_HOLE_D   =  3.2;
 FC_POS_Y    = ROVER_L/2 - 65.0;   // near front edge
 

docs/AGENTS.md

@@ -1,184 +1,323 @@
-# AGENTS.md — SAUL-TEE Agent Onboarding
+# AGENTS.md — SaltyLab Agent Onboarding
 
-You're working on **SAUL-TEE**, a 4-wheel wagon robot. Read this entire file before touching anything.
+You're working on **SaltyLab**, a self-balancing two-wheeled indoor robot. Read this entire file before touching anything.
 
-**Full system reference:** `docs/SAUL-TEE-SYSTEM-REFERENCE.md`
+## ⚠️ ARCHITECTURE — SAUL-TEE (finalised 2026-04-04)
 
-## Project Overview
+<<<<<<< HEAD
+Full hardware spec: `docs/SAUL-TEE-SYSTEM-REFERENCE.md` — **read it before writing firmware.**
 
-A 4-wheel wagon robot (870×510×550 mm, 23 kg) with three compute layers:
-
-1. **ESP32-S3 BALANCE** (Waveshare Touch LCD 1.28) — QMI8658 IMU, PID drive / stability loop, CAN bus master for VESCs. Safety-critical layer. Firmware in `esp32/balance/`.
-2. **ESP32-S3 IO** (bare board) — RC input (TBS Crossfire + ELRS failover), BTS7960 motor drivers, I2C sensors (NFC/baro/ToF), WS2812 LEDs, accessories. Firmware in `esp32/io/`.
-3. **Jetson Orin Nano Super** — AI brain: ROS2, SLAM, Nav2, perception. Sends high-level velocity commands over CAN (0x300–0x303). Receives telemetry on CAN (0x400–0x401).
+| Board | Role |
+|-------|------|
+| **ESP32-S3 BALANCE** | Waveshare Touch LCD 1.28 (CH343 USB). QMI8658 IMU, PID loop, CAN→VESC L(68)/R(56), GC9A01 LCD |
+| **ESP32-S3 IO** | Bare devkit (JTAG USB). TBS Crossfire RC (UART0), ELRS failover (UART2), BTS7960 motors, NFC/baro/ToF, WS2812, buzzer/horn/headlight/fan |
+| **Jetson Orin** | CANable2 USB→CAN. Cmds on 0x300–0x303, telemetry on 0x400–0x401 |
 
 ```
-Orin (CAN 0x300-0x303)  ←→  TBS Crossfire / ELRS (CRSF @ 420000)
+Jetson Orin ──CANable2──► CAN 500kbps ◄───────────────────────┐
                                 │                               │
-         ▼ CAN 500kbps                  │ inter-board UART 460800
- ESP32-S3 BALANCE ───────────────── ESP32-S3 IO
-   QMI8658 IMU                         BTS7960 × 4 motor drivers
-   PID loop                            NFC / baro / ToF (I2C)
-   SN65HVD230 CAN                      WS2812 LEDs
-         │                             Horn / headlight / fan / buzzer
-         ▼ CAN 500kbps
-  VESC left (ID 68)   VESC right (ID 56)
-         │                    │
-     Hub motors FL/RL     Hub motors FR/RR
+                         ESP32-S3 BALANCE ←─UART 460800─► ESP32-S3 IO
+                         (QMI8658, PID loop)              (BTS7960, RC, sensors)
+                                │ CAN 500kbps
+                      ┌─────────┴──────────┐
+                 VESC Left (ID 68)    VESC Right (ID 56)
+=======
+A hoverboard-based balancing robot with two compute layers:
+1. **ESP32-S3 BALANCE** — ESP32-S3 BALANCE (ESP32-S3RET6 + MPU6000 IMU). Runs a lean C balance loop at up to 8kHz. Talks UART to the hoverboard ESC. This is the safety-critical layer.
+2. **Jetson Orin Nano Super** — AI brain. ROS2, SLAM, person tracking. Sends velocity commands to FC via UART. Not safety-critical — FC operates independently.
+
 ```
+Jetson (speed+steer via UART1)  ←→  ELRS RC (UART3, kill switch)
+         │
+         ▼
+   ESP32-S3 BALANCE (MPU6000 IMU, PID balance)
+         │
+         ▼ UART2
+   Hoverboard ESC (FOC) → 2× 8" hub motors
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+```
+
+Frame: `[0xAA][LEN][TYPE][PAYLOAD][CRC8]`  
+Legacy `src/` STM32 HAL code is **archived — do not extend.**
 
 ## ⚠️ SAFETY — READ THIS OR PEOPLE GET HURT
 
-This is not a toy. 4× hub motors + 36V × high-current VESCs can crush fingers, break toes, and throw the 23 kg frame. Every firmware change must preserve these invariants:
+This is not a toy. 8" hub motors + 36V battery can crush fingers, break toes, and launch the frame. Every firmware change must preserve these invariants:
 
-1. **Motors NEVER spin on power-on.** Requires deliberate arming: deliberate ARM command.
-2. **RC kill switch** — dedicated ELRS/Crossfire channel, checked every loop iteration. Always overrides.
-3. **CAN watchdog** — if no Orin heartbeat for 500 ms, drop to RC-only mode.
-4. **ESTOP CAN frame** — 0x303 with magic byte 0xE5 cuts all motors instantly.
-5. **Inter-board heartbeat** — if IO board misses BALANCE heartbeat for 200 ms, IO disables all BTS7960 enables.
+1. **Motors NEVER spin on power-on.** Requires deliberate arming: hold button 3s while upright.
+2. **Tilt cutoff at ±25°** — motors to zero, require manual re-arm. No retry, no recovery.
+3. **Hardware watchdog (50ms)** — if firmware hangs, motors cut.
+4. **RC kill switch** — dedicated ELRS channel, checked every loop iteration. Always overrides.
+5. **Jetson UART timeout (200ms)** — if Jetson disconnects, motors cut.
 6. **Speed hard cap** — firmware limit, start at 10%. Increase only after proven stable.
-7. **Never test without RC transmitter in hand.**
+7. **Never test untethered** until PID is stable for 5+ minutes on a tether.
 
 **If you break any of these, you are removed from the project.**
 
 ## Repository Layout
 
 ```
-esp32/
-├── balance/          — ESP32-S3 BALANCE firmware (PlatformIO)
-│   ├── src/
-│   │   ├── main.cpp
-│   │   ├── config.h      ← GPIO assignments — update here first
-│   │   ├── imu_qmi8658.cpp/.h
-│   │   ├── can_vesc.cpp/.h
-│   │   └── protocol.cpp/.h
-│   └── platformio.ini
-├── io/               — ESP32-S3 IO firmware (PlatformIO)
-│   ├── src/
-│   │   ├── main.cpp
-│   │   ├── config.h      ← GPIO assignments — update here first
-│   │   ├── rc_crsf.cpp/.h
-│   │   ├── motor_bts7960.cpp/.h
-│   │   └── protocol.cpp/.h
-│   └── platformio.ini
-└── shared/
-    └── protocol.h    ← inter-board frame types — authoritative
+<<<<<<< HEAD
+firmware/              # Legacy ESP32/STM32 HAL firmware (PlatformIO, archived)
+=======
+firmware/              # ESP-IDF firmware (PlatformIO)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+├── src/
+│   ├── main.c         # Entry point, clock config, main loop
+│   ├── icm42688.c     # QMI8658-P SPI driver (backup IMU — currently broken)
+│   ├── bmp280.c       # Barometer driver (disabled)
+│   └── status.c       # LED + buzzer status patterns
+├── include/
+│   ├── config.h       # Pin definitions, constants
+│   ├── icm42688.h
+│   ├── mpu6000.h      # MPU6000 driver header (primary IMU)
+│   ├── hoverboard.h   # Hoverboard ESC UART protocol
+│   ├── crsf.h         # ELRS CRSF protocol
+│   ├── bmp280.h
+│   └── status.h
+├── lib/USB_CDC/       # USB Serial (CH343) stack (serial over USB)
+│   ├── src/           # CDC implementation, USB descriptors, PCD config
+│   └── include/
+└── platformio.ini     # Build config
 
-src/                  — LEGACY STM32 code (ARCHIVED — do not touch)
-include/              — LEGACY STM32 headers (ARCHIVED — do not touch)
+cad/                   # OpenSCAD parametric parts (16 files)
+├── dimensions.scad    # ALL measurements live here — single source of truth
+├── assembly.scad      # Full robot assembly visualization
+├── motor_mount_plate.scad
+├── battery_shelf.scad
+├── fc_mount.scad      # Vibration-isolated FC mount
+├── jetson_shelf.scad
+├── esc_mount.scad
+├── sensor_tower_top.scad
+├── lidar_standoff.scad
+├── realsense_bracket.scad
+├── bumper.scad        # TPU bumpers (front + rear)
+├── handle.scad
+├── kill_switch_mount.scad
+├── tether_anchor.scad
+├── led_diffuser_ring.scad
+└── esp32c3_mount.scad
 
-chassis/              — OpenSCAD mechanical parts
-├── ASSEMBLY.md       — assembly instructions
-├── BOM.md            — bill of materials
-└── *.scad            — parametric parts
+ui/                    # Web UI (Three.js + WebSerial)
+└── index.html         # 3D board visualization, real-time IMU data
 
-docs/
-├── SAUL-TEE-SYSTEM-REFERENCE.md  ← MASTER REFERENCE — read this
-├── AGENTS.md                     — this file
-├── wiring-diagram.md             — wiring reference (see SAUL-TEE-SYSTEM-REFERENCE.md)
-└── SALTYLAB.md                   — legacy design doc (historical)
+SALTYLAB.md            # Master design doc — architecture, wiring, build phases
+SALTYLAB-DETAILED.md   # Power budget, weight budget, detailed schematics
+PLATFORM.md            # Hardware platform reference
 ```
 
 ## Hardware Quick Reference
 
-### ESP32-S3 BALANCE (Waveshare Touch LCD 1.28)
+<<<<<<< HEAD
+### ESP32 BALANCE Flight Controller
 
 | Spec | Value |
 |------|-------|
-| MCU | ESP32-S3, dual-core 240 MHz, 8MB flash, 8MB PSRAM |
-| USB | CH343G USB-UART bridge (UART0 / GPIO43 TX, GPIO44 RX) |
-| Display | 1.28" round GC9A01 240×240 (SPI, onboard) |
-| IMU | QMI8658 6-axis (I2C-0 SDA=GPIO6, SCL=GPIO7, INT=GPIO3) |
-| CAN | SN65HVD230 external transceiver (GPIO TBD — see `esp32/balance/src/config.h`) |
-| Inter-board UART | UART1 (GPIO TBD) ↔ ESP32-IO @ 460800 baud |
+| MCU | ESP32RET6 (Cortex-M7, 216MHz, 512KB flash, 256KB RAM) |
+=======
+### ESP32-S3 BALANCE Flight Controller
 
-### ESP32-S3 IO (bare board)
+| Spec | Value |
+|------|-------|
+| MCU | ESP32-S3RET6 (Cortex-M7, 216MHz, 512KB flash, 256KB RAM) |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+| Primary IMU | MPU6000 (WHO_AM_I = 0x68) |
+| IMU Bus | SPI1: PA5=SCK, PA6=MISO, PA7=MOSI, CS=PA4 |
+| IMU EXTI | PC4 (data ready interrupt) |
+| IMU Orientation | CW270 (Betaflight convention) |
+| Secondary IMU | QMI8658-P (on same SPI1, CS unknown — currently non-functional) |
+| Betaflight Target | DIAT-MAMBAF722_2022B |
+| USB | OTG FS (PA11/PA12), enumerates as /dev/cu.usbmodemSALTY0011 |
+| VID/PID | 0x0483/0x5740 |
+| LEDs | PC15 (LED1), PC14 (LED2), active low |
+| Buzzer | PB2 (inverted push-pull) |
+| Battery ADC | PC1=VBAT, PC3=CURR (ADC3) |
+| DFU | Hold yellow BOOT button + plug USB (or send 'R' over CDC) |
 
-| Peripheral | Interface | GPIO |
-|------------|-----------|------|
-| TBS Crossfire RX | UART0 CRSF @ 420000 | GPIO43 TX / GPIO44 RX |
-| ELRS failover RX | UART2 CRSF @ 420000 | TBD |
-| BTS7960 FL/FR/RL/RR | PWM + GPIO | TBD — see config.h |
-| I2C bus (NFC/baro/ToF) | I2C | TBD |
-| WS2812B LEDs | RMT GPIO | TBD |
-| Horn / headlight / fan / buzzer | GPIO/PWM | TBD |
-| Inter-board UART | UART1 @ 460800 | TBD |
+### UART Assignments
 
-> All TBD GPIO assignments are confirmed in `esp32/io/src/config.h`.
+| UART | Pins | Connected To | Baud |
+|------|------|-------------|------|
+| USART1 | PA9/PA10 | Jetson Orin Nano Super | 115200 |
+| USART2 | PA2/PA3 | Hoverboard ESC | 115200 |
+| USART3 | PB10/PB11 | ELRS Receiver | 420000 (CRSF) |
+| UART4 | — | Spare | — |
+| UART5 | — | Spare | — |
 
-### CAN Bus
+### Motor/ESC
 
-| Node | CAN ID | Notes |
-|------|--------|-------|
-| VESC left motor | 68 (0x44) | FSESC 6.7 Pro Mini Dual |
-| VESC right motor | 56 (0x38) | FSESC 6.7 Pro Mini Dual |
-| Orin → robot cmds | 0x300–0x303 | drive / arm / PID / ESTOP |
-| BALANCE → Orin telemetry | 0x400–0x401 | attitude + battery + faults |
+- 2× 8" pneumatic hub motors (36V, hoverboard type)
+- Hoverboard ESC with FOC firmware
+- UART protocol: `{0xABCD, int16 speed, int16 steer, uint16 checksum}` at 115200
+- Speed range: -1000 to +1000
 
-### Physical Dimensions
+### Physical Dimensions (from `cad/dimensions.scad`)
 
-| Parameter | Value |
-|-----------|-------|
-| Robot (SAUL-TEE) | 870 × 510 × 550 mm, 23 kg |
-| Hub motor axle base OD | Ø16.11 mm (caliper-verified) |
-| Hub motor axle D-cut OD | Ø15.95 mm, 13.00 mm flat chord |
-| Bearing seat collar | Ø37.8 mm |
-| Tire | 10 × 2.125" pneumatic (Ø254 mm) |
-| ESP32-S3 BALANCE PCB | ~40×40 mm (TBD — caliper before machining) |
-| Orin carrier hole pattern | 58 × 49 mm M3 |
+| Part | Key Measurement |
+|------|----------------|
+| FC mounting holes | 25.5mm spacing (NOT standard 30.5mm!) |
+| FC board size | ~36mm square |
+| Hub motor body | Ø200mm (~8") |
+| Motor axle | Ø12mm, 45mm long |
+| Jetson Orin Nano Super | 100×80×29mm, M2.5 holes at 86×58mm |
+| RealSense D435i | 90×25×25mm, 1/4-20 tripod mount |
+| RPLIDAR A1 | Ø70×41mm, 4× M2.5 on Ø67mm circle |
+| Kill switch hole | Ø22mm panel mount |
+| Battery pack | ~180×80×40mm |
+| Hoverboard ESC | ~80×50×15mm |
+| 2020 extrusion | 20mm square, M5 center bore |
+| Frame width | ~350mm (axle to axle) |
+| Frame height | ~500-550mm total |
+| Target weight | <8kg (current estimate: 7.4kg) |
 
-## Inter-Board Protocol
+### 3D Printed Parts (16 files in `cad/`)
 
-**UART @ 460800 baud, 8N1.** Frame: `[0xAA][LEN][TYPE][PAYLOAD…][CRC8]`
+| Part | Material | Infill |
+|------|----------|--------|
+| motor_mount_plate (350×150×6mm) | PETG | 80% |
+| battery_shelf | PETG | 60% |
+| esc_mount | PETG | 40% |
+| jetson_shelf | PETG | 40% |
+| sensor_tower_top | ASA | 80% |
+| lidar_standoff (Ø80×80mm) | ASA | 40% |
+| realsense_bracket | PETG | 60% |
+| fc_mount (vibration isolated) | TPU+PETG | — |
+| bumper front + rear (350×50×30mm) | TPU | 30% |
+| handle | PETG | 80% |
+| kill_switch_mount | PETG | 80% |
+| tether_anchor | PETG | 100% |
+| led_diffuser_ring (Ø120×15mm) | Clear PETG | 30% |
+| esp32c3_mount | PETG | 40% |
 
-CRC polynomial: CRC-8/MAXIM (poly 0x31, init 0x00, RefIn/RefOut true).
+## Firmware Architecture
 
-Authoritative message type definitions: `esp32/shared/protocol.h`
+### Critical Lessons Learned (DON'T REPEAT THESE)
 
-## Build & Flash
+1. **SysTick_Handler with HAL_IncTick() is MANDATORY** — without it, HAL_Delay() and every HAL timeout hangs forever. This bricked us multiple times.
+<<<<<<< HEAD
+2. **DCache breaks SPI on ESP32** — disable DCache or use cache-aligned DMA buffers with clean/invalidate. We disable it.
+=======
+2. **DCache breaks SPI on ESP32-S3** — disable DCache or use cache-aligned DMA buffers with clean/invalidate. We disable it.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+3. **`-(int)0 == 0`** — checking `if (-result)` to detect errors doesn't work when result is 0 (success and failure look the same). Always use explicit error codes.
+4. **NEVER auto-run untested code on_boot** — we bricked the NSPanel 3x doing this. Test manually first.
+5. **USB Serial (CH343) needs ReceivePacket() primed in CDC_Init** — without it, the OUT endpoint never starts listening. No data reception.
+
+### DFU Reboot (Betaflight Method)
+
+The firmware supports reboot-to-DFU via USB command:
+1. Send `R` byte over USB Serial (CH343)
+2. Firmware writes `0xDEADBEEF` to RTC backup register 0
+3. `NVIC_SystemReset()` — clean hardware reset
+4. On boot, `checkForBootloader()` (called after `HAL_Init()`) reads the magic
+<<<<<<< HEAD
+5. If magic found: clears it, remaps system memory, jumps to ESP32 BALANCE bootloader at `0x1FF00000`
+=======
+5. If magic found: clears it, remaps system memory, jumps to ESP32-S3 bootloader at `0x1FF00000`
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+6. Board appears as DFU device, ready for `dfu-util` flash
+
+### Build & Flash
 
 ```bash
-# ESP32-S3 BALANCE
-cd esp32/balance
-pio run -t upload                  # Upload via USB (CH343 serial)
-
-# ESP32-S3 IO
-cd esp32/io
-pio run -t upload                  # Upload via USB (JTAG/CDC)
+cd firmware/
+python3 -m platformio run                    # Build
+dfu-util -a 0 -s 0x08000000:leave -D .pio/build/f722/firmware.bin  # Flash
 ```
 
-## Critical Lessons Learned
+Dev machine: mbpm4 (seb@192.168.87.40), PlatformIO project at `~/Projects/saltylab-firmware/`
 
-1. **`-(int)0 == 0`** — checking `if (-result)` doesn't detect a zero error result. Use explicit error codes.
-2. **NEVER auto-run untested firmware on boot** — we bricked hardware doing this. Test manually first.
-3. **One variable at a time** — never change PID gains and speed limit in the same test session.
-4. **QMI8658 data ready** — poll INT pin (GPIO3) or use interrupt; don't poll status register in a tight loop.
-5. **CAN bus termination** — 120 Ω at each physical end of the bus. Missing termination = unreliable comms.
+### Clock Configuration
 
-## LED States (WS2812B on ESP32-IO)
+```
+HSE 8MHz → PLL (M=8, N=432, P=2, Q=9) → SYSCLK 216MHz
+PLLSAI (N=384, P=8) → CLK48 48MHz (USB)
+APB1 = HCLK/4 = 54MHz
+APB2 = HCLK/2 = 108MHz
+Fallback: HSI 16MHz if HSE fails (PLL M=16)
+```
+
+## Current Status & Known Issues
+
+### Working
+- USB Serial (CH343) serial streaming (50Hz JSON: `{"ax":...,"ay":...,"az":...,"gx":...,"gy":...,"gz":...}`)
+- Clock config with HSE + HSI fallback
+- Reboot-to-DFU via USB 'R' command
+- LED status patterns (status.c)
+- Web UI with WebSerial + Three.js 3D visualization
+
+### Broken / In Progress
+- **QMI8658-P SPI reads return all zeros** — was the original IMU target, but SPI communication completely non-functional despite correct pin config. May be dead silicon. Switched to MPU6000 as primary.
+- **MPU6000 driver** — header exists but implementation needs completion
+- **PID balance loop** — not yet implemented
+- **Hoverboard ESC UART** — protocol defined, driver not written
+- **ELRS CRSF receiver** — protocol defined, driver not written
+- **Barometer (BMP280)** — I2C init hangs, disabled
+
+### TODO (Priority Order)
+1. Get MPU6000 streaming accel+gyro data
+2. Implement complementary filter (pitch angle)
+3. Write hoverboard ESC UART driver
+4. Write PID balance loop with safety checks
+5. Wire ELRS receiver, implement CRSF parser
+6. Bench test (ESC disconnected, verify PID output)
+7. First tethered balance test at 10% speed
+8. Jetson UART integration
+9. LED subsystem (ESP32-C3)
+
+## Communication Protocols
+
+### Jetson → FC (UART1, 50Hz)
+```c
+struct { uint8_t header=0xAA; int16_t speed; int16_t steer; uint8_t mode; uint8_t checksum; };
+// mode: 0=idle, 1=balance, 2=follow, 3=RC
+```
+
+### FC → Hoverboard ESC (UART2, loop rate)
+```c
+struct { uint16_t start=0xABCD; int16_t speed; int16_t steer; uint16_t checksum; };
+// speed/steer: -1000 to +1000
+```
+
+### FC → Jetson Telemetry (UART1 TX, 50Hz)
+```
+T:12.3,P:45,L:100,R:-80,S:3\n
+// T=tilt°, P=PID output, L/R=motor commands, S=state (0-3)
+```
+
+### FC → USB Serial (CH343) (50Hz JSON)
+```json
+{"ax":123,"ay":-456,"az":16384,"gx":10,"gy":-5,"gz":3,"t":250,"p":0,"bt":0}
+// Raw IMU values (int16), t=temp×10, p=pressure, bt=baro temp
+```
+
+## LED Subsystem (ESP32-C3)
+
+ESP32-C3 eavesdrops on FC→Jetson telemetry (listen-only tap on UART1 TX). No extra FC UART needed.
 
 | State | Pattern | Color |
 |-------|---------|-------|
 | Disarmed | Slow breathe | White |
 | Arming | Fast blink | Yellow |
-| Armed | Solid | Green |
+| Armed idle | Solid | Green |
 | Turning | Sweep direction | Orange |
 | Braking | Flash rear | Red |
-| Fault / ESTOP | Triple flash | Red |
+| Fault | Triple flash | Red |
 | RC lost | Alternating flash | Red/Blue |
 
 ## Printing (Bambu Lab)
 
-- **X1C** (192.168.87.190) — structural PETG/ASA parts
-- **A1** (192.168.86.161) — TPU bumpers, prototypes
+- **X1C** (192.168.87.190) — for structural PETG/ASA parts
+- **A1** (192.168.86.161) — for TPU bumpers and prototypes
+- LAN access codes and MQTT details in main workspace MEMORY.md
 - STL export from OpenSCAD, slice in Bambu Studio
 
 ## Rules for Agents
 
-1. **Read `docs/SAUL-TEE-SYSTEM-REFERENCE.md`** fully before any design or firmware decision
-2. **Never remove safety checks** — add more if needed
-3. **All mechanical measurements go in `cad/dimensions.scad`** — single source of truth
-4. **Test firmware on bench first** — VESCs/BTS7960 disconnected, verify outputs on serial
-5. **GPIO assignments live in `config.h`** — change there, not scattered in source
-6. **Document hardware quirks here** — if you find a gotcha, add a "Critical Lesson Learned"
-7. **Ask before wiring changes** — wrong connections can fry ESP32-S3 boards
+1. **Read SALTYLAB.md fully** before making any design decisions
+2. **Never remove safety checks** from firmware — add more if needed
+3. **All measurements go in `cad/dimensions.scad`** — single source of truth
+4. **Test firmware on bench before any motor test** — ESC disconnected, verify outputs on serial
+5. **One variable at a time** — don't change PID and speed limit in the same test
+6. **Document what you change** — update this file if you add pins, change protocols, or discover hardware quirks
+7. **Ask before wiring changes** — wrong connections can fry the FC ($50+ board)

docs/FACE_LCD_ANIMATION.md

@@ -1,6 +1,10 @@
 # Face LCD Animation System (Issue #507)
 
-Implements expressive face animations on the ESP32-S3 BALANCE board LCD display (Waveshare Touch LCD 1.28, GC9A01 1.28" round 240×240) with 5 core emotions and smooth transitions.
+<<<<<<< HEAD
+Implements expressive face animations on an ESP32 LCD display with 5 core emotions and smooth transitions.
+=======
+Implements expressive face animations on an ESP32-S3 LCD display with 5 core emotions and smooth transitions.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ## Features
 
@@ -82,9 +86,13 @@ STATUS      → Echo current emotion + idle state
 - Colors: Monochrome (1-bit) or RGB565
 
 ### Microcontroller
-- ESP32-S3 BALANCE (Waveshare Touch LCD 1.28)
-- Receives emotion commands from Orin via CAN (0x300 mode byte) or inter-board UART
-- Clock: 240 MHz
+<<<<<<< HEAD
+- ESP32xx (ESP32 BALANCE)
+=======
+- ESP32-S3xx (ESP32-S3 BALANCE)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+- Available UART: USART3 (PB10=TX, PB11=RX)
+- Clock: 216 MHz
 
 ## Animation Timing
 

docs/SALTYLAB.md

@@ -1,6 +1,6 @@
-# SaltyLab — Self-Balancing Indoor Bot 🔬
+# SAUL-TEE — Self-Balancing Wagon Robot 🔬
 
-Two-wheeled, self-balancing robot for indoor AI/SLAM experiments.
+Four-wheel wagon (870×510×550 mm, 23 kg). Full spec: `docs/SAUL-TEE-SYSTEM-REFERENCE.md`
 
 ## ⚠️ SAFETY — TOP PRIORITY
 
@@ -11,7 +11,7 @@ Two-wheeled, self-balancing robot for indoor AI/SLAM experiments.
 2. **Software tilt cutoff** — if pitch exceeds ±25° (not 30°), motors go to zero immediately. No retry, no recovery. Requires manual re-arm.
 3. **Startup arming sequence** — motors NEVER spin on power-on. Requires deliberate arming: hold button for 3 seconds while robot is upright and stable.
 4. **Watchdog timeout** — if FC firmware hangs or crashes, hardware watchdog resets to safe state (motors off) within 50ms.
-5. **Current limiting** — VESC max current set conservatively. Start low, increase gradually.
+5. **Current limiting** — hoverboard ESC max current set conservatively. Start low, increase gradually.
 6. **Tether during development** — ceiling rope/strap during ALL balance testing. No free-standing tests until PID is proven stable for 5+ minutes tethered.
 7. **Speed limiting** — firmware hard cap on max speed. Start at 10% throttle, increase in 10% increments only after stable testing.
 8. **Remote kill** — Jetson can send emergency stop via UART. If Jetson disconnects (UART timeout >200ms), FC cuts motors automatically.
@@ -31,9 +31,8 @@ Two-wheeled, self-balancing robot for indoor AI/SLAM experiments.
 | Part | Status |
 |------|--------|
 | 2x 8" pneumatic hub motors (36 PSI) | ✅ Have |
-| 2x VESC FSESC 6.7 Pro Mini Dual (left ID 68, right ID 56) | ✅ Have |
-| 1x ESP32-S3 BALANCE (Waveshare Touch LCD 1.28) | ⬜ Need — PID loop + CAN master |
-| 1x ESP32-S3 IO (bare board) | ⬜ Need — RC / motor / sensor I/O |
+| 1x hoverboard ESC (FOC firmware) | ✅ Have |
+| 1x Drone FC (ESP32-S3 + QMI8658) | ✅ Have — balance brain |
 | 1x Jetson Orin Nano Super + Noctua fan | ✅ Have |
 | 1x RealSense D435i | ✅ Have |
 | 1x RPLIDAR A1M8 | ✅ Have |
@@ -48,24 +47,21 @@ Two-wheeled, self-balancing robot for indoor AI/SLAM experiments.
 | 1x Arming button (momentary, with LED) | ⬜ Need |
 | 1x Ceiling tether strap + carabiner | ⬜ Need |
 | 1x BetaFPV ELRS 2.4GHz 1W TX module | ✅ Have — RC control + kill switch |
-| 1x ELRS receiver (matching) | ✅ Have — failover RC on ESP32-IO UART2 |
+| 1x ELRS receiver (matching) | ✅ Have — mounts on FC UART |
 
-### ESP32-S3 BALANCE (Waveshare Touch LCD 1.28)
-- **MCU:** ESP32-S3, dual-core 240 MHz, 8MB flash, 8MB PSRAM
-- **Display:** 1.28" round GC9A01 240×240 LCD (face animations)
-- **IMU:** QMI8658 6-axis (I2C-0 SDA=GPIO6, SCL=GPIO7) — onboard
-- **CAN:** SN65HVD230 external transceiver → 500 kbps CAN to VESCs
-- **USB:** CH343G bridge (UART0 GPIO43/44) — programming + debug
-- **Firmware:** `esp32/balance/` (PlatformIO, Arduino framework)
-- **Role:** PID / stability loop, VESC CAN master, inter-board UART to IO board
-
-### ESP32-S3 IO (bare board)
-- **USB:** Built-in JTAG/USB-CDC — programming + debug
-- **RC:** TBS Crossfire on UART0 (GPIO43/44), ELRS failover on UART2
-- **Drive:** 4× BTS7960 H-bridge drivers for hub motors (GPIO TBD)
-- **Sensors:** NFC, barometer, ToF distance (shared I2C, GPIO TBD)
-- **Outputs:** WS2812B LEDs (RMT), horn, headlight, fan, buzzer
-- **Firmware:** `esp32/io/` (PlatformIO, Arduino framework)
+### ESP32-S3 BALANCE Board Details — Waveshare ESP32-S3 Touch LCD 1.28
+- **MCU:** ESP32-S3RET6 (Xtensa LX7 dual-core, 240MHz, 8MB Flash, 512KB SRAM)
+- **IMU:** QMI8658 (6-axis, 32kHz gyro, ultra-low noise, SPI) ← the good one!
+- **Display:** 1.28" round LCD (GC9A01 driver, 240x240)
+- **DFU mode:** Hold BOOT button while plugging USB
+- **Firmware:** Custom balance firmware (ESP-IDF / Arduino-ESP32)
+- **USB:** USB Serial via CH343 chip
+- **UART assignments:**
+  - UART0 → USB Serial (CH343) → debug/flash
+  - UART1 → Jetson Orin Nano Super
+  - UART2 → Hoverboard ESC
+  - UART3 → ELRS receiver
+  - UART4/5 → spare
 
 ## Architecture
 
@@ -77,102 +73,61 @@ Two-wheeled, self-balancing robot for indoor AI/SLAM experiments.
                     │ RealSense    │ ← Forward-facing depth+RGB
                     │ D435i        │
                     ├──────────────┤
-                    │ Jetson Orin  │ ← AI brain: ROS2, SLAM, Nav2
-                    │ Nano Super   │   Sends CAN cmds 0x300–0x303
+                    │ Jetson Orin Nano Super  │ ← AI brain: navigation, person tracking
+                    │              │   Sends velocity commands via UART
                     ├──────────────┤
-                    │ ESP32-S3     │ ← Balance brain: QMI8658 IMU + PID
-                    │ BALANCE      │   CAN master to VESCs (SN65HVD230)
-                    ├──────────────┤
-                    │ ESP32-S3 IO  │ ← RC (CRSF/ELRS), sensors, LEDs
+                    │ Drone FC     │ ← Balance brain: IMU + PID @ 8kHz
+                    │ F745+MPU6000 │   Custom firmware, UART out to ESC
                     ├──────────────┤
                     │ Battery 36V  │
                     │ + DC-DCs     │
                     ├──────┬───────┤
-              ┌─────┤ VESC Left    ├─────┐
-              │     │ (ID 68)      │     │
-              │     │ VESC Right   │     │
-              │     │ (ID 56)      │     │
+              ┌─────┤  ESC (FOC)   ├─────┐
+              │     │  Hoverboard  │     │
               │     └──────────────┘     │
            ┌──┴──┐                   ┌──┴──┐
-           │ Hub │                   │ Hub │
-           │motor│                   │motor│
+           │ 8"  │                   │ 8"  │
+           │ LEFT│                   │RIGHT│
            └─────┘                   └─────┘
 ```
 
-## Self-Balancing Control — Custom Firmware on ESP32-S3 BALANCE
+## Self-Balancing Control — ESP32-S3 BALANCE Board
+
+> For full system architecture, firmware details, and protocol specs, see
+> **docs/SAUL-TEE-SYSTEM-REFERENCE.md**
+
+The balance controller runs on the Waveshare ESP32-S3 Touch LCD 1.28 board
+(ESP32-S3 BALANCE). It reads the onboard QMI8658 IMU at 8kHz, runs a PID
+balance loop, and drives the hoverboard ESC via UART. Jetson Orin Nano Super
+sends velocity commands over UART1. ELRS receiver on UART3 provides RC
+override and kill-switch capability.
+
+The legacy STM32 firmware (Mamba F722S era) has been archived to
+=======
+The legacy STM32 firmware (STM32 era) has been archived to
+`legacy/stm32/` and is no longer built or deployed.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+## LED Subsystem (ESP32-C3)
 
 ### Architecture
-```
-Jetson Orin (CAN 0x300–0x303)
-    │  - Drive cmd: speed + steer
-    │  - Arm/disarm, PID tune, ESTOP
-    ▼
-ESP32-S3 BALANCE (PlatformIO / Arduino)
-    │  - Reads QMI8658 IMU @ I2C (GPIO6/7)
-    │  - Runs PID balance loop
-    │  - Mixes balance correction + Orin velocity cmd
-    │  - Sends VESC CAN commands (SN65HVD230, 500 kbps)
-    │  - Inter-board UART @ 460800 → ESP32-S3 IO
-    ▼
-VESC Left (CAN ID 68)   VESC Right (CAN ID 56)
-    │                         │
-  FL + RL hub motors     FR + RR hub motors
-```
-
-### Wiring
+The ESP32-C3 eavesdrops on the FC→Jetson telemetry UART line (listen-only, one wire).
+No extra UART needed on the FC — zero firmware change.
 
 ```
-Jetson Orin              CANable 2.0
-────────────             ──────────
-USB-A            ──→     USB-B
-                         CANH ──→ CAN bus CANH
-                         CANL ──→ CAN bus CANL
-
-ESP32-S3 BALANCE         SN65HVD230 transceiver
-────────────────         ──────────────────────
-CAN TX (GPIO TBD) ──→    D pin
-CAN RX (GPIO TBD) ←──    R pin
-                         CANH ──→ CAN bus CANH
-                         CANL ──→ CAN bus CANL
-
-ESP32-S3 BALANCE         ESP32-S3 IO
-────────────────         ───────────
-UART1 TX (TBD)   ──→     UART1 RX (TBD)
-UART1 RX (TBD)   ←──     UART1 TX (TBD)
-GND              ──→     GND
-
-TBS Crossfire RX         ESP32-S3 IO
-────────────────         ───────────
-TX               ──→     GPIO44 (UART0 RX)
-RX               ←──     GPIO43 (UART0 TX)
-GND              ──→     GND
-5V               ←──     5V
-```
-
-### PID Tuning
-| Param | Starting Value | Notes |
-|-------|---------------|-------|
-| Kp | 30-50 | Main balance response |
-| Ki | 0.5-2 | Drift correction |
-| Kd | 0.5-2 | Damping oscillation |
-| Loop rate | 1 kHz | QMI8658 data-ready driven (GPIO3 INT) |
-| Max tilt | ±25° | Beyond this = cut motors, require re-arm |
-| CAN_WATCHDOG_MS | 500 | Drop to RC-only if Orin CAN heartbeat lost |
-| max_speed_limit | 10% | Start at 10%, increase after stable testing |
-| SPEED_TO_ANGLE_FACTOR | 0.01-0.05 | How much lean per speed unit |
-
-## LED Subsystem (ESP32-S3 IO)
-
-### Architecture
-WS2812B LEDs are driven directly by the ESP32-S3 IO board via its RMT peripheral.
-The IO board receives robot state over inter-board UART from ESP32-S3 BALANCE.
-
-```
-ESP32-S3 BALANCE ──UART 460800──→ ESP32-S3 IO
+FC UART1 TX ──┬──→ Jetson RX
+              └──→ ESP32-C3 RX (listen-only, same wire)
                    │
-                                       └──RMT──→ WS2812B strip
+                   └──→ WS2812B strip (via RMT peripheral)
 ```
 
+### Telemetry Format (already sent by FC at 50Hz)
+```
+T:12.3,P:45,L:100,R:-80,S:3\n
+                          ^-- State byte: 0=disarmed, 1=arming, 2=armed, 3=fault
+```
+ESP32-C3 parses the `S:` field and `L:/R:` for turn detection.
+
 ### LED Patterns
 | State | Pattern | Color |
 |-------|---------|-------|
@@ -185,18 +140,25 @@ ESP32-S3 BALANCE ──UART 460800──→ ESP32-S3 IO
 | Fault | Triple flash | Red |
 | RC signal lost | Alternating flash | Red/Blue |
 
+### Turn/Brake Detection (on ESP32-C3)
+```
+if (L - R > threshold)  → turning right
+if (R - L > threshold)  → turning left
+if (L < -threshold && R < -threshold) → braking
+```
+
 ### Wiring
 ```
-ESP32-S3 IO RMT GPIO (TBD) ──→ WS2812B data in
-5V bus                     ──→ WS2812B 5V + ESP32-S3 IO VCC
+FC UART1 TX pin ──→ ESP32-C3 GPIO RX (e.g. GPIO20)
+ESP32-C3 GPIO8  ──→ WS2812B data in
+ESC 5V BEC      ──→ ESP32-C3 5V + WS2812B 5V
 GND             ──→ Common ground
 ```
 
 ### Dev Tools
-- **Flashing BALANCE:** `pio run -t upload` in `esp32/balance/` via CH343G USB
-- **Flashing IO:** `pio run -t upload` in `esp32/io/` via JTAG/USB-CDC
-- **IDE:** PlatformIO + Arduino framework (ESP32)
-- **Debug:** USB serial monitor (`pio device monitor`), logic analyzer on UART/CAN
+- **Flashing:** ESP32-S3CubeProgrammer via USB (DFU mode) or SWD
+- **IDE:** PlatformIO + ESP-IDF, or ESP32-S3CubeIDE
+- **Debug:** SWD via ST-Link (or use FC's USB as virtual COM for printf debug)
 
 ## Physical Design
 
@@ -211,7 +173,7 @@ GND                        ──→ Common ground
     ├───────────┤                 ├─────────────────┤
     │  Jetson   │ ~300mm          │    [Jetson]     │
     ├───────────┤                 ├─────────────────┤
-    │ ESP32-S3  │ ~200mm          │   [BALANCE]     │
+    │ Drone FC  │ ~200mm          │   [Drone FC]    │
     ├───────────┤                 ├─────────────────┤
     │  Battery  │ ~100mm          │   [Battery]     │
     │  + ESC    │  LOW!           │   [ESC+DCDC]    │
@@ -251,8 +213,7 @@ GND                        ──→ Common ground
 | Sensor tower top | 120×120×10 | ASA 80% | 1 |
 | LIDAR standoff | Ø80×80 | ASA 40% | 1 |
 | RealSense bracket | 100×50×40 | PETG 60% | 1 |
-| MCU mount — ESP32-S3 BALANCE | TBD×TBD×15 | TPU+PETG | 1 |
-| MCU mount — ESP32-S3 IO | TBD×TBD×15 | PETG | 1 |
+| FC mount (vibration isolated) | 30×30×15 | TPU+PETG | 1 |
 | Bumper front | 350×50×30 | TPU 30% | 1 |
 | Bumper rear | 350×50×30 | TPU 30% | 1 |
 | Handle (for carrying) | 150×30×30 | PETG 80% | 1 |
@@ -264,14 +225,14 @@ GND                        ──→ Common ground
 ## Software Stack
 
 ### Jetson Orin Nano Super
-- **OS:** JetPack 6.x (Ubuntu 22.04)
-- **ROS2 Humble** for:
+- **OS:** JetPack 4.6.1 (Ubuntu 18.04)
+- **ROS2 Humble** (or Foxy) for:
   - `nav2` — navigation stack
   - `slam_toolbox` — 2D SLAM from LIDAR
   - `realsense-ros` — depth camera
   - `rplidar_ros` — LIDAR driver
-- **Person following:** SSD-MobileNet-v2 via TensorRT (~30+ FPS)
-- **Balance commands:** ROS topic → CAN bus → ESP32-S3 BALANCE (CANable 2.0, can0, 500 kbps)
+- **Person following:** SSD-MobileNet-v2 via TensorRT (~20 FPS)
+- **Balance commands:** ROS topic → UART bridge to drone FC
 
 ### Modes
 1. **Idle** — self-balancing in place, waiting for command
@@ -290,34 +251,33 @@ GND                        ──→ Common ground
 - [ ] Install hardware kill switch inline with 36V battery (NC — press to kill)
 - [ ] Set up ceiling tether point above test area (rated for >15kg)
 - [ ] Clear test area: 3m radius, no loose items, shoes on
-- [ ] Set up PlatformIO projects for ESP32-S3 BALANCE + IO (`esp32/balance/`, `esp32/io/`)
-- [ ] Confirm QMI8658 I2C comms on GPIO6/7 (INT on GPIO3); verify IMU data on serial
+- [ ] Set up PlatformIO project for ESP32-S3 (ESP-IDF)
+- [ ] Write QMI8658 SPI driver (read gyro+accel, complementary filter)
 - [ ] Write PID balance loop with ALL safety checks:
   - ±25° tilt cutoff → disarm, require manual re-arm
-  - CAN watchdog 500 ms (drop to RC-only if Orin silent)
-  - Speed limit at 10%
-  - Arming sequence (deliberate ARM command required on power-on)
-- [ ] Write VESC CAN commands (SN65HVD230 transceiver, 500 kbps, IDs 68/56)
-- [ ] Flash BALANCE via CH343G USB: `cd esp32/balance && pio run -t upload`
-- [ ] Write TBS Crossfire CRSF driver on IO board (UART0 GPIO43/44, 420000 baud)
-- [ ] Bind TBS TX ↔ RX, verify channel data on IO board serial monitor
-- [ ] Map radio: CH1=steer, CH2=speed, CH5=arm/disarm, CH6=mode
-- [ ] Flash IO via JTAG/USB-CDC: `cd esp32/io && pio run -t upload`
-- [ ] **Bench test first** — BALANCE powered but VESCs disconnected; verify IMU + PID output + RC channels on serial; no motors spin
-- [ ] Wire BALANCE CAN TX/RX → SN65HVD230 → CAN bus → VESCs
-- [ ] Build minimal frame: motor plate + battery + VESCs + ESP32-S3 boards
-- [ ] Power ESP32s from 5V DC-DC
+  - Watchdog timer (50ms hardware WDT)
+  - Speed limit at 10% (max_speed_limit = 100)
+  - Arming sequence (3s hold while upright)
+- [ ] Write hoverboard ESC UART output (speed+steer protocol)
+- [ ] Flash firmware via USB DFU (boot0 jumper on FC)
+- [ ] Write ELRS CRSF receiver driver (UART3, parse channels + arm switch)
+- [ ] Bind ELRS TX ↔ RX, verify channel data on serial monitor
+- [ ] Map radio: CH1=steer, CH2=speed, CH5=arm/disarm switch
+- [ ] **Bench test first** — FC powered but ESC disconnected, verify IMU reads + PID output + RC channels on serial monitor
+- [ ] Wire FC UART2 → hoverboard ESC UART
+- [ ] Build minimal frame: motor plate + battery + ESC + FC
+- [ ] Power FC from ESC 5V BEC
 - [ ] **First balance test — TETHERED, kill switch in hand, 10% speed limit**
 - [ ] Tune PID at 10% speed until stable tethered for 5+ minutes
 - [ ] Gradually increase speed limit (10% increments, 5 min stable each)
 
 ### Phase 2: Brain (Week 2)
-- [ ] Mount Jetson Orin Nano Super + power (DC-DC 5V via USB-C PD)
+- [ ] Mount Jetson + power (DC-DC 5V)
 - [ ] Set up JetPack + ROS2
-- [ ] Bring up CANable 2.0 on Orin: `ip link set can0 up type can bitrate 500000`
-- [ ] Send drive CAN frames (0x300) from Orin → BALANCE firmware receives + acts
-- [ ] ROS2 node: subscribe to `/cmd_vel`, publish CAN drive frames
-- [ ] Test: keyboard teleoperation via ROS2 while balancing
+- [ ] Add Jetson UART RX to FC firmware (receive speed+steer commands)
+- [ ] Wire Jetson UART1 → FC UART1
+- [ ] Python serial bridge: send speed+steer, read telemetry
+- [ ] Test: keyboard teleoperation while balancing
 
 ### Phase 3: Senses (Week 3)
 - [ ] Mount RealSense + RPLIDAR
@@ -327,9 +287,10 @@ GND                        ──→ Common ground
 
 ### Phase 4: Polish (Week 4)
 - [ ] Print proper enclosures, bumpers, diffuser ring
-- [ ] Implement WS2812B LED patterns in ESP32-S3 IO firmware (RMT, state from inter-board UART)
+- [ ] Wire ESP32-C3 to FC telemetry TX line (listen-only tap)
+- [ ] Flash ESP32-C3: parse telemetry, drive WS2812B via RMT
 - [ ] Mount LED strip around frame with diffuser
-- [ ] Test all LED patterns: disarmed/arming/armed/turning/fault/RC-lost
-- [ ] Speaker / buzzer audio feedback (IO board GPIO)
-- [ ] WiFi status dashboard (serve from Orin or IO board AP)
-- [ ] Emergency stop button wired to IO board GPIO → ESTOP CAN frame 0x303
+- [ ] Test all LED patterns: disarmed/arming/armed/turning/fault
+- [ ] Speaker for audio feedback
+- [ ] WiFi status dashboard (ESP32-C3 can serve this too)
+- [ ] Emergency stop button

docs/board-viz.html

@@ -2,7 +2,7 @@
 <html>
 <head>
 <meta charset="utf-8">
-<title>ESP32-S3 BALANCE — Waveshare Touch LCD 1.28 Pinout</title>
+<title>GEPRC GEP-F722-45A AIO — Board Layout (Legacy / Archived)</title>
 <style>
 * { margin: 0; padding: 0; box-sizing: border-box; }
 body { background: #1a1a2e; color: #eee; font-family: 'Courier New', monospace; display: flex; flex-direction: column; align-items: center; padding: 20px; }
@@ -10,219 +10,274 @@ h1 { color: #e94560; margin-bottom: 5px; font-size: 1.4em; }
 .subtitle { color: #888; margin-bottom: 20px; font-size: 0.85em; }
 .container { display: flex; gap: 30px; align-items: flex-start; flex-wrap: wrap; justify-content: center; }
 .board-wrap { position: relative; }
-.board { width: 400px; height: 380px; background: #1a472a; border: 3px solid #333; border-radius: 50%; position: relative; box-shadow: 0 0 20px rgba(0,0,0,0.5); display: flex; align-items: center; justify-content: center; }
-.board::before { content: 'Waveshare Touch LCD 1.28'; position: absolute; top: 30px; left: 50%; transform: translateX(-50%); color: #fff3; font-size: 9px; letter-spacing: 1px; white-space: nowrap; }
+.board { width: 400px; height: 340px; background: #1a472a; border: 3px solid #333; border-radius: 8px; position: relative; box-shadow: 0 0 20px rgba(0,0,0,0.5); }
+.board::before { content: 'GEPRC GEP-F722-45A AIO'; position: absolute; top: 8px; left: 50%; transform: translateX(-50%); color: #fff3; font-size: 10px; letter-spacing: 2px; }
 
-/* LCD circle */
-.lcd { width: 180px; height: 180px; background: #111; border: 3px solid #444; border-radius: 50%; position: absolute; display: flex; align-items: center; justify-content: center; font-size: 9px; color: #64B5F6; text-align: center; line-height: 1.6; }
-.lcd-inner { text-align: center; }
+/* Mounting holes */
+.mount { width: 10px; height: 10px; background: #111; border: 2px solid #555; border-radius: 50%; position: absolute; }
+.mount.tl { top: 15px; left: 15px; }
+.mount.tr { top: 15px; right: 15px; }
+.mount.bl { bottom: 15px; left: 15px; }
+.mount.br { bottom: 15px; right: 15px; }
 
-/* MCU chip */
-.mcu-label { position: absolute; top: 95px; left: 50%; transform: translateX(-50%); font-size: 8px; color: #aaa; text-align: center; white-space: nowrap; }
+/* MCU */
+.mcu { width: 80px; height: 80px; background: #222; border: 1px solid #555; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); display: flex; align-items: center; justify-content: center; font-size: 9px; color: #aaa; text-align: center; line-height: 1.3; }
+.mcu .dot { width: 5px; height: 5px; background: #666; border-radius: 50%; position: absolute; top: 4px; left: 4px; }
+
+/* IMU */
+.imu { width: 32px; height: 32px; background: #333; border: 1px solid #e94560; position: absolute; top: 85px; left: 60px; display: flex; align-items: center; justify-content: center; font-size: 7px; color: #e94560; }
+.imu::after { content: 'CW90°'; position: absolute; bottom: -14px; color: #e94560; font-size: 8px; white-space: nowrap; }
+
+/* Arrow showing CW90 rotation */
+.rotation-arrow { position: absolute; top: 72px; left: 55px; color: #e94560; font-size: 18px; }
+
+/* Pads */
+.pad { position: absolute; display: flex; align-items: center; gap: 4px; font-size: 10px; cursor: pointer; }
+.pad .dot { width: 12px; height: 12px; border-radius: 50%; border: 2px solid; display: flex; align-items: center; justify-content: center; font-size: 7px; font-weight: bold; }
+.pad:hover .label { color: #fff; }
+.pad .label { transition: color 0.2s; }
+.pad .sublabel { font-size: 8px; color: #888; }
+
+/* UART colors */
+.uart1 .dot { background: #2196F3; border-color: #64B5F6; }
+.uart2 .dot { background: #FF9800; border-color: #FFB74D; }
+.uart3 .dot { background: #9C27B0; border-color: #CE93D8; }
+.uart4 .dot { background: #4CAF50; border-color: #81C784; }
+.uart5 .dot { background: #F44336; border-color: #EF9A9A; }
 
 /* Component dots */
-.comp { position: absolute; font-size: 9px; color: #ccc; }
+.comp { position: absolute; font-size: 9px; display: flex; align-items: center; gap: 4px; }
+.comp .icon { width: 10px; height: 10px; border-radius: 2px; }
+
+/* LED */
+.led-blue { position: absolute; width: 8px; height: 8px; background: #2196F3; border-radius: 50%; box-shadow: 0 0 8px #2196F3; top: 45px; right: 50px; }
+.led-label { position: absolute; top: 36px; right: 30px; font-size: 8px; color: #64B5F6; }
+
+/* Boot button */
+.boot-btn { position: absolute; width: 16px; height: 10px; background: #b8860b; border: 1px solid #daa520; border-radius: 2px; bottom: 45px; right: 40px; }
+.boot-label { position: absolute; bottom: 32px; right: 30px; font-size: 8px; color: #daa520; }
 
 /* USB */
-.usb { position: absolute; width: 36px; height: 14px; background: #444; border: 2px solid #777; border-radius: 3px; bottom: 25px; left: 50%; transform: translateX(-50%); }
-.usb-label { position: absolute; bottom: 44px; left: 50%; transform: translateX(-50%); font-size: 8px; color: #999; white-space: nowrap; }
+.usb { position: absolute; width: 30px; height: 14px; background: #444; border: 2px solid #777; border-radius: 3px; bottom: -3px; left: 50%; transform: translateX(-50%); }
+.usb-label { position: absolute; bottom: 14px; left: 50%; transform: translateX(-50%); font-size: 8px; color: #999; }
 
-/* Pin rows */
-.pin-row { position: absolute; display: flex; flex-direction: column; gap: 4px; }
-.pin { display: flex; align-items: center; gap: 4px; font-size: 10px; }
-.pin .dot { width: 10px; height: 10px; border-radius: 50%; border: 2px solid; flex-shrink: 0; }
-.pin .name { min-width: 70px; }
-.pin .sublabel { font-size: 8px; color: #888; }
+/* Connector pads along edges */
+/* Bottom row: T1 R1 T3 R3 */
+.pad-t1 { bottom: 20px; left: 40px; }
+.pad-r1 { bottom: 20px; left: 80px; }
+.pad-t3 { bottom: 20px; left: 140px; }
+.pad-r3 { bottom: 20px; left: 180px; }
 
-/* Left side pins */
-.pins-left { left: 10px; top: 60px; }
-.pins-left .pin { flex-direction: row; }
+/* Right side: T2 R2 */
+.pad-t2 { right: 20px; top: 80px; flex-direction: row-reverse; }
+.pad-r2 { right: 20px; top: 110px; flex-direction: row-reverse; }
 
-/* Right side pins */
-.pins-right { right: 10px; top: 60px; }
-.pins-right .pin { flex-direction: row-reverse; text-align: right; }
+/* Top row: T4 R4 T5 R5 */
+.pad-t4 { top: 30px; left: 40px; }
+.pad-r4 { top: 30px; left: 80px; }
+.pad-t5 { top: 30px; right: 100px; flex-direction: row-reverse; }
+.pad-r5 { top: 30px; right: 55px; flex-direction: row-reverse; }
 
-/* Colors by function */
-.imu .dot   { background: #e94560; border-color: #ff6b81; }
-.can .dot   { background: #FF9800; border-color: #FFB74D; }
-.uart .dot  { background: #2196F3; border-color: #64B5F6; }
-.spi .dot   { background: #9C27B0; border-color: #CE93D8; }
-.pwr .dot   { background: #4CAF50; border-color: #81C784; }
-.io .dot    { background: #607D8B; border-color: #90A4AE; }
+/* ESC pads (motor outputs - not used) */
+.esc-pads { position: absolute; left: 20px; top: 140px; }
+.esc-pads .esc-label { font-size: 8px; color: #555; }
 
 /* Legend */
-.legend { background: #16213e; padding: 15px 20px; border-radius: 8px; min-width: 290px; }
+.legend { background: #16213e; padding: 15px 20px; border-radius: 8px; min-width: 280px; }
 .legend h2 { color: #e94560; font-size: 1.1em; margin-bottom: 10px; border-bottom: 1px solid #333; padding-bottom: 5px; }
 .legend-item { display: flex; align-items: center; gap: 8px; margin: 6px 0; font-size: 12px; }
 .legend-item .swatch { width: 14px; height: 14px; border-radius: 50%; flex-shrink: 0; }
+.legend-item .arrow { color: #888; font-size: 10px; }
 .legend-section { margin-top: 12px; padding-top: 8px; border-top: 1px solid #333; }
 .legend-section h3 { font-size: 0.9em; color: #888; margin-bottom: 6px; }
 
+/* Orientation guide */
+.orient { margin-top: 20px; background: #16213e; padding: 15px 20px; border-radius: 8px; width: 100%; max-width: 710px; }
+.orient h2 { color: #4CAF50; font-size: 1.1em; margin-bottom: 10px; }
+.orient-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
+.orient-item { font-size: 12px; padding: 6px 10px; background: #1a1a2e; border-radius: 4px; }
+.orient-item .dir { color: #4CAF50; font-weight: bold; }
+
+/* Axis overlay */
+.axis { position: absolute; }
+.axis-x { top: 50%; right: -60px; color: #F44336; font-size: 12px; font-weight: bold; }
+.axis-y { bottom: -30px; left: 50%; transform: translateX(-50%); color: #4CAF50; font-size: 12px; font-weight: bold; }
+.axis-arrow-x { position: absolute; top: 50%; right: -45px; transform: translateY(-50%); width: 30px; height: 2px; background: #F44336; }
+.axis-arrow-x::after { content: '▶'; position: absolute; right: -12px; top: -8px; color: #F44336; }
+.axis-arrow-y { position: absolute; bottom: -20px; left: 50%; transform: translateX(-50%); width: 2px; height: 20px; background: #4CAF50; }
+.axis-arrow-y::after { content: '▼'; position: absolute; bottom: -14px; left: -5px; color: #4CAF50; }
+
 .note { margin-top: 15px; color: #888; font-size: 11px; text-align: center; max-width: 710px; }
 .note em { color: #e94560; font-style: normal; }
 </style>
 </head>
 <body>
-<h1>🤖 ESP32-S3 BALANCE — Waveshare Touch LCD 1.28</h1>
-<p class="subtitle">ESP32-S3 240 MHz | QMI8658 IMU | GC9A01 1.28″ LCD | CH343G USB-UART | SN65HVD230 CAN</p>
+<<<<<<< HEAD
+<h1>🤖 GEPRC GEP-F722-45A AIO — SaltyLab Pinout (Legacy / Archived)</h1>
+<p class="subtitle">ESP32RET6 + ICM-42688-P | Betaflight target: GEPR-GEPRC_F722_AIO</p>
+=======
+<h1>🤖 GEPRC GEP-F722-45A AIO — SaltyLab Pinout</h1>
+<p class="subtitle">ESP32-S3RET6 + ICM-42688-P | Betaflight target: GEPR-GEPRC_F722_AIO</p>
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 <div class="container">
   <div class="board-wrap">
     <div class="board">
-      <!-- LCD circle -->
-      <div class="lcd">
-        <div class="lcd-inner">GC9A01<br>1.28″ round<br>240×240<br>SPI</div>
-      </div>
-      <div class="mcu-label">ESP32-S3<br>240 MHz / 8MB</div>
+      <!-- Mounting holes -->
+      <div class="mount tl"></div>
+      <div class="mount tr"></div>
+      <div class="mount bl"></div>
+      <div class="mount br"></div>
 
-      <!-- USB CH343G -->
-      <div class="usb-label">USB-A CH343G (UART0 debug/flash)</div>
+      <!-- MCU -->
+<<<<<<< HEAD
+      <div class="mcu"><div class="dot"></div>ESP32<br>(legacy:<br>F722RET6)</div>
+=======
+      <div class="mcu"><div class="dot"></div>ESP32-S3<br>F722RET6<br>216MHz</div>
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+      <!-- IMU -->
+      <div class="imu">ICM<br>42688</div>
+      <div class="rotation-arrow">↻</div>
+
+      <!-- LED -->
+      <div class="led-blue"></div>
+      <div class="led-label">LED PC4</div>
+
+      <!-- Boot button -->
+      <div class="boot-btn"></div>
+      <div class="boot-label">BOOT 🟡</div>
+
+      <!-- USB -->
       <div class="usb"></div>
+      <div class="usb-label">USB-C (DFU)</div>
 
-      <!-- Left-side pins (onboard fixed) -->
-      <div class="pin-row pins-left">
-        <div class="pin imu">
-          <div class="dot"></div>
-          <span class="name">GPIO6</span>
-          <span class="sublabel">IMU SDA (I2C-0)</span>
+      <!-- UART Pads - Bottom -->
+      <div class="pad pad-t1 uart1">
+        <div class="dot">T</div>
+        <span class="label">T1<br><span class="sublabel">PA9</span></span>
       </div>
-        <div class="pin imu">
-          <div class="dot"></div>
-          <span class="name">GPIO7</span>
-          <span class="sublabel">IMU SCL (I2C-0)</span>
+      <div class="pad pad-r1 uart1">
+        <div class="dot">R</div>
+        <span class="label">R1<br><span class="sublabel">PA10</span></span>
       </div>
-        <div class="pin imu">
-          <div class="dot"></div>
-          <span class="name">GPIO3</span>
-          <span class="sublabel">QMI8658 INT</span>
-        </div>
-        <div class="pin uart">
-          <div class="dot"></div>
-          <span class="name">GPIO43</span>
-          <span class="sublabel">UART0 TX (CH343G)</span>
-        </div>
-        <div class="pin uart">
-          <div class="dot"></div>
-          <span class="name">GPIO44</span>
-          <span class="sublabel">UART0 RX (CH343G)</span>
-        </div>
-        <div class="pin uart">
-          <div class="dot"></div>
-          <span class="name">UART1 TX</span>
-          <span class="sublabel">Inter-board → IO (TBD)</span>
-        </div>
-        <div class="pin uart">
-          <div class="dot"></div>
-          <span class="name">UART1 RX</span>
-          <span class="sublabel">Inter-board ← IO (TBD)</span>
+      <div class="pad pad-t3 uart3">
+        <div class="dot">T</div>
+        <span class="label">T3<br><span class="sublabel">PB10</span></span>
       </div>
+      <div class="pad pad-r3 uart3">
+        <div class="dot">R</div>
+        <span class="label">R3<br><span class="sublabel">PB11</span></span>
       </div>
 
-      <!-- Right-side pins (external) -->
-      <div class="pin-row pins-right">
-        <div class="pin can">
-          <div class="dot"></div>
-          <span class="name">CAN TX</span>
-          <span class="sublabel">→ SN65HVD230 D (TBD)</span>
+      <!-- UART Pads - Right -->
+      <div class="pad pad-t2 uart2">
+        <span class="label">T2<br><span class="sublabel">PA2</span></span>
+        <div class="dot">T</div>
       </div>
-        <div class="pin can">
-          <div class="dot"></div>
-          <span class="name">CAN RX</span>
-          <span class="sublabel">← SN65HVD230 R (TBD)</span>
+      <div class="pad pad-r2 uart2">
+        <span class="label">R2<br><span class="sublabel">PA3</span></span>
+        <div class="dot">R</div>
       </div>
-        <div class="pin spi">
-          <div class="dot"></div>
-          <span class="name">LCD SPI</span>
-          <span class="sublabel">GC9A01 (onboard)</span>
+
+      <!-- UART Pads - Top -->
+      <div class="pad pad-t4 uart4">
+        <div class="dot">T</div>
+        <span class="label">T4<br><span class="sublabel">PC10</span></span>
       </div>
-        <div class="pin pwr">
-          <div class="dot"></div>
-          <span class="name">5V</span>
-          <span class="sublabel">USB / ext 5V in</span>
+      <div class="pad pad-r4 uart4">
+        <div class="dot">R</div>
+        <span class="label">R4<br><span class="sublabel">PC11</span></span>
       </div>
-        <div class="pin pwr">
-          <div class="dot"></div>
-          <span class="name">3.3V</span>
-          <span class="sublabel">LDO out</span>
+      <div class="pad pad-t5 uart5">
+        <span class="label">T5<br><span class="sublabel">PC12</span></span>
+        <div class="dot">T</div>
       </div>
-        <div class="pin pwr">
-          <div class="dot"></div>
-          <span class="name">GND</span>
-          <span class="sublabel">Common ground</span>
+      <div class="pad pad-r5 uart5">
+        <span class="label">R5<br><span class="sublabel">PD2</span></span>
+        <div class="dot">R</div>
       </div>
+
+      <!-- ESC motor pads label -->
+      <div class="esc-pads">
+        <div class="esc-label">M1-M4 (unused)<br>PC6-PC9</div>
       </div>
+
+      <!-- Board axes -->
+      <div class="axis-arrow-x"></div>
+      <div class="axis axis-x">X →<br><span style="font-size:9px;color:#888">board right</span></div>
+      <div class="axis-arrow-y"></div>
+      <div class="axis axis-y">Y ↓ (board forward = tilt axis)</div>
     </div>
   </div>
 
   <div class="legend">
-    <h2>📌 Pin Assignments</h2>
+    <h2>🔌 UART Assignments</h2>
     <div class="legend-item">
-      <div class="swatch" style="background:#e94560"></div>
-      <span><b>IMU (QMI8658)</b> — I2C-0 SDA=GPIO6, SCL=GPIO7, INT=GPIO3</span>
+      <div class="swatch" style="background:#2196F3"></div>
+      <span><b>USART1</b> T1/R1 → Jetson Orin Nano Super</span>
     </div>
     <div class="legend-item">
       <div class="swatch" style="background:#FF9800"></div>
-      <span><b>CAN (SN65HVD230)</b> — TX/RX TBD; confirm in <code>esp32/balance/src/config.h</code></span>
-    </div>
-    <div class="legend-item">
-      <div class="swatch" style="background:#2196F3"></div>
-      <span><b>UART0</b> GPIO43/44 — CH343G USB bridge (debug + flash)</span>
-    </div>
-    <div class="legend-item">
-      <div class="swatch" style="background:#2196F3"></div>
-      <span><b>UART1</b> TBD — Inter-board @ 460800 baud → ESP32-S3 IO</span>
+      <span><b>USART2</b> T2 → Hoverboard ESC (TX only)</span>
     </div>
     <div class="legend-item">
       <div class="swatch" style="background:#9C27B0"></div>
-      <span><b>LCD SPI</b> — GC9A01 1.28″ round 240×240 (onboard, fixed pins)</span>
+      <span><b>I2C2</b> T3/R3 → Baro/Mag (reserved)</span>
     </div>
     <div class="legend-item">
       <div class="swatch" style="background:#4CAF50"></div>
-      <span><b>Power</b> — 5V USB input; 3.3V LDO for logic + sensors</span>
+      <span><b>UART4</b> T4/R4 → ELRS RX (CRSF)</span>
+    </div>
+    <div class="legend-item">
+      <div class="swatch" style="background:#F44336"></div>
+      <span><b>UART5</b> T5/R5 → Debug/spare</span>
     </div>
 
     <div class="legend-section">
-      <h3>🔌 CAN Bus Topology</h3>
+      <h3>📡 SPI Bus</h3>
       <div class="legend-item">
-        <span>Orin → CANable 2.0 → <b>CANH/CANL</b> (500 kbps)</span>
+        <span>SPI1: PA5/PA6/PA7 → IMU (CS: <em style="color:#e94560">PA15</em>)</span>
       </div>
       <div class="legend-item">
-        <span>BALANCE: SN65HVD230 on CAN bus</span>
+        <span>SPI2: PB13-15 → OSD MAX7456</span>
       </div>
       <div class="legend-item">
-        <span>VESC Left: ID <b>0x44</b> (68) | VESC Right: ID <b>0x38</b> (56)</span>
-      </div>
-      <div class="legend-item">
-        <span>120 Ω termination at each bus end</span>
+        <span>SPI3: PB3-5 → Flash W25Q128</span>
       </div>
     </div>
 
     <div class="legend-section">
-      <h3>📡 Inter-Board Protocol</h3>
+      <h3>⚡ Other</h3>
       <div class="legend-item">
-        <span>UART @ 460800 baud, 8N1</span>
+        <span>🔵 LED: PC4 | 📢 Beeper: PC15</span>
       </div>
       <div class="legend-item">
-        <span>Frame: <code>[0xAA][LEN][TYPE][PAYLOAD][CRC8]</code></span>
+        <span>🔋 VBAT: PC2 | ⚡ Current: PC1</span>
       </div>
       <div class="legend-item">
-        <span>Types: see <code>esp32/shared/protocol.h</code></span>
+        <span>💡 LED Strip: PA1 (WS2812)</span>
       </div>
+      <div class="legend-item">
+        <span>📍 EXTI (IMU data-ready): PA8</span>
       </div>
-
-    <div class="legend-section">
-      <h3>⚡ Safety</h3>
-      <div class="legend-item"><span>Motors NEVER spin on power-on — ARM required</span></div>
-      <div class="legend-item"><span>RC kill switch checked every loop</span></div>
-      <div class="legend-item"><span>CAN watchdog: 500 ms → RC-only mode</span></div>
-      <div class="legend-item"><span>ESTOP: CAN 0x303 + 0xE5 → all motors off</span></div>
     </div>
   </div>
 </div>
 
+<div class="orient">
+  <h2>🧭 IMU Orientation (CW90° from chip to board)</h2>
+  <div class="orient-grid">
+    <div class="orient-item"><span class="dir">Board Forward</span> (tilt for balance) = Chip's +Y axis</div>
+    <div class="orient-item"><span class="dir">Board Right</span> = Chip's -X axis</div>
+    <div class="orient-item"><span class="dir">Board Pitch Rate</span> = -Gyro X (raw)</div>
+    <div class="orient-item"><span class="dir">Board Accel Forward</span> = Accel Y (raw)</div>
+  </div>
+</div>
+
 <p class="note">
-  ⚠️ CAN TX/RX GPIO assignments are <em>TBD</em> — confirm in <code>esp32/balance/src/config.h</code> before wiring.
-  All inter-board UART GPIO also TBD. LCD and IMU pins are fixed by Waveshare hardware.
+  ⚠️ Pad positions are <em>approximate</em> — check the physical board silkscreen for exact locations.
+  The CW90 rotation is handled in firmware (mpu6000.c). USB-C at bottom edge for DFU flashing.
 </p>
 
 </body>

docs/wiring-diagram.md

@@ -1,174 +1,212 @@
-# SAUL-TEE Wiring Reference
+# SaltyLab / SAUL-TEE Wiring Reference
 
-**Authoritative reference:** [`docs/SAUL-TEE-SYSTEM-REFERENCE.md`](SAUL-TEE-SYSTEM-REFERENCE.md)
-
-This document is a quick-access wiring summary. For pin assignments, CAN frame formats,
-RC channel mapping, and serial commands, see the full reference doc.
+> ⚠️ **ARCHITECTURE CHANGE (2026-04-03):** Mamba F722S / STM32 retired.
+> New stack: **ESP32-S3 BALANCE** + **ESP32-S3 IO** + VESCs on 500 kbps CAN.
+> **Authoritative reference:** [`docs/SAUL-TEE-SYSTEM-REFERENCE.md`](SAUL-TEE-SYSTEM-REFERENCE.md)
+> Historical STM32/Mamba wiring below is **obsolete** — retained for reference only.
 
 ---
 
-## System Block Diagram
+## ~~System Overview~~ (OBSOLETE — see SAUL-TEE-SYSTEM-REFERENCE.md)
 
 ```
-                    ┌──────────────────────────────────────────────────────────┐
-                    │               JETSON ORIN NANO SUPER                     │
-                    │                  (Top plate, 25W)                        │
+┌─────────────────────────────────────────────────────────────────────┐
+│                        ORIN NANO SUPER                              │
+│                     (Top Plate — 25W)                               │
+│                                                                     │
+<<<<<<< HEAD
+│  USB-A ──── CANable2 USB-CAN adapter (slcan0, 500 kbps)           │
+│  USB-A ──── ESP32-S3 IO (/dev/esp32-io, 460800 baud)              │
+=======
+│  USB-C ──── ESP32-S3 CDC (/dev/esp32-bridge, 921600 baud)            │
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+│  USB-A1 ─── RealSense D435i (USB 3.1)                             │
+│  USB-A2 ─── RPLIDAR A1M8 (via CP2102 adapter, 115200)             │
+│  USB-C* ─── SIM7600A 4G/LTE modem (ttyUSB0-2, AT cmds + PPP)     │
+│  USB ─────── Leap Motion Controller (hand/gesture tracking)        │
+│  CSI-A ──── ArduCam adapter → 2x IMX219 (front + left)            │
+│  CSI-B ──── ArduCam adapter → 2x IMX219 (rear + right)            │
+│  M.2 ───── 1TB NVMe SSD                                            │
+│  40-pin ─── ReSpeaker 2-Mic HAT (I2S + I2C, WM8960 codec)         │
+│  Pin 8 ──┐                                                         │
+│  Pin 10 ─┤ UART fallback to ESP32-S3 BALANCE (ttyTHS0, 460800)    │
+│  Pin 6 ──┘ GND                                                     │
+│                                                                     │
+└─────────────────────────────────────────────────────────────────────┘
+         │ USB-A (CANable2)               │ UART fallback (3 wires)
+         │ SocketCAN slcan0               │ 460800 baud, 3.3V
+         │ 500 kbps                       │
+         ▼                                ▼
+┌─────────────────────────────────────────────────────────────────────┐
+<<<<<<< HEAD
+│                  ESP32-S3 BALANCE                                    │
+│          (Waveshare Touch LCD 1.28, Middle Plate)                   │
+=======
+│                     ESP32-S3 BALANCE (FC)                                 │
+│                  (Middle Plate — foam mounted)                       │
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+│                                                                     │
+│  CAN bus ──── CANable2 → Orin (primary link, ISO 11898)            │
+│  UART0 ──── Orin UART fallback (460800 baud, 3.3V)                │
+│  UART1 ──── VESC Left  (CAN ID 56) via UART/CAN bridge            │
+│  UART2 ──── VESC Right (CAN ID 68) via UART/CAN bridge            │
+│  I2C   ──── QMI8658 IMU (onboard, 6-DOF accel+gyro)               │
+│  SPI   ──── GC9A01 LCD (onboard, 240x240 round display)           │
+│  GPIO  ──── WS2812B LED strip                                      │
+│  GPIO  ──── Buzzer                                                  │
+│  ADC   ──── Battery voltage divider                                │
+│                                                                     │
+└─────────────────────────────────────────────────────────────────────┘
+         │ CAN bus (ISO 11898)            │ UART (460800 baud)
+         │ 500 kbps                       │
+         ▼                                ▼
+┌────────────────────────┐    ┌──────────────────────────┐
+│   VESC Left (ID 56)    │    │   VESC Right (ID 68)     │
+│   (Bottom Plate)       │    │   (Bottom Plate)          │
+│                        │    │                            │
+│  BLDC hub motor        │    │  BLDC hub motor            │
+│  CAN 500 kbps          │    │  CAN 500 kbps             │
+│  FOC current control   │    │  FOC current control      │
+│  VESC Status 1 (0x900) │    │  VESC Status 1 (0x910)   │
+│                        │    │                            │
+└────────────────────────┘    └──────────────────────────┘
          │                              │
-                    │  USB-A ──── CANable 2.0 USB↔CAN (can0, 500 kbps)       │
-                    │  USB-A ──── RealSense D435i (USB 3.1)                  │
-                    │  USB-A ──── RPLIDAR A1M8 (CP2102, 115200)              │
-                    │  USB-C ──── SIM7600A 4G/LTE modem                      │
-                    │  CSI-A ─── 2× IMX219 cameras (front + left)            │
-                    │  CSI-B ─── 2× IMX219 cameras (rear + right)            │
-                    │  40-pin ── ReSpeaker 2-Mic HAT                          │
-                    └──────────────────────┬───────────────────────────────────┘
-                                           │ USB-A → CANable 2.0
-                                           │ can0, 500 kbps
-          ┌────────────────────────────────┴──────────────────────────────────┐
-          │                    CAN BUS  (CANH / CANL / GND)                   │
-          │              120 Ω ─┤                     ├─ 120 Ω               │
-          └───────────┬──────────────────────────────────────────┬────────────┘
-                      │                                          │
-          ┌───────────┴────────────┐              ┌─────────────┴──────────┐
-          │  ESP32-S3 BALANCE      │              │  VESC left  (ID 68)    │
-          │  Waveshare Touch LCD   │              │  VESC right (ID 56)    │
-          │  1.28 — CH343 USB      │              │  FSESC 6.7 Pro Mini    │
-          │                        │              │  Dual                  │
-          │  QMI8658 IMU (I2C)     │              └──────┬─────────────────┘
-          │  SN65HVD230 (CAN)      │                     │ Phase wires
-          │                        │            ┌────────┴─────────────┐
-          │  UART ──────────────┐  │            │  Hub motors (4×)     │
-          └────────────────────────┘            │  FL / FR / RL / RR   │
-            ↕ 460800 baud binary │              └──────────────────────┘
-              inter-board proto  │
-          ┌───────────────────────┘
-          │  ESP32-S3 IO (bare board)
-          │  JTAG USB
-          │
-          │  UART0 ── TBS Crossfire RX (CRSF @ 420000)
-          │  UART2 ── ELRS receiver (CRSF failover @ 420000)
-          │  PWM ──── 4× BTS7960 H-bridge motor drivers
-          │  I2C ──── NFC + Barometer + ToF (shared bus)
-          │  RMT ──── WS2812B LED strip
-          │  GPIO ─── Horn / Headlight / Fan / Buzzer
-          └──────────────────────────────────────────────
+    LEFT MOTOR                    RIGHT MOTOR
 ```
 
----
 
 ## Wire-by-Wire Connections
 
-### 1. Orin ↔ CAN Bus (via CANable 2.0)
+<<<<<<< HEAD
+### 1. Orin <-> ESP32-S3 BALANCE (Primary: CAN Bus via CANable2)
+=======
+### 1. Orin ↔ FC (Primary: USB Serial (CH343))
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+| From | To | Wire | Notes |
+|------|----|------|-------|
+| Orin USB-A | CANable2 USB | USB cable | SocketCAN slcan0 @ 500 kbps |
+| CANable2 CAN-H | ESP32-S3 BALANCE CAN-H | twisted pair | ISO 11898 differential |
+| CANable2 CAN-L | ESP32-S3 BALANCE CAN-L | twisted pair | ISO 11898 differential |
+
+<<<<<<< HEAD
+- Interface: SocketCAN `slcan0`, 500 kbps
+- Device node: `/dev/canable2` (via udev, symlink to ttyUSBx)
+- Protocol: CAN frames --- ORIN_CMD_DRIVE (0x300), ORIN_CMD_MODE (0x301), ORIN_CMD_ESTOP (0x302)
+- Telemetry: BALANCE_STATUS (0x400), BALANCE_VESC (0x401), BALANCE_IMU (0x402), BALANCE_BATTERY (0x403)
+=======
+- Device: `/dev/ttyACM0` → symlink `/dev/esp32-bridge`
+- Baud: 921600, 8N1
+- Protocol: JSON telemetry (FC→Orin), ASCII commands (Orin→FC)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+### 2. Orin <-> ESP32-S3 BALANCE (Fallback: Hardware UART)
+
+| Orin Pin | Signal | ESP32-S3 Pin | Notes |
+|----------|--------|--------------|-------|
+| Pin 8 | TXD0 | GPIO17 (UART0 RX) | Orin TX -> BALANCE RX |
+| Pin 10 | RXD0 | GPIO18 (UART0 TX) | Orin RX <- BALANCE TX |
+| Pin 6 | GND | GND | Common ground |
+
+- Jetson device: `/dev/ttyTHS0`
+- Baud: 460800, 8N1
+- Voltage: 3.3V both sides (no level shifter needed)
+- Cross-connect: Orin TX -> BALANCE RX, Orin RX <- BALANCE TX
+
+### 3. Orin <-> ESP32-S3 IO (USB Serial)
 
 | From | To | Notes |
 |------|----|-------|
-| Orin USB-A | CANable 2.0 USB | `/dev/canable0` → `can0` |
-| CANable CANH | CAN bus CANH | Twisted pair |
-| CANable CANL | CAN bus CANL | Twisted pair |
-| CANable GND | CAN GND | Common |
+| Orin USB-A | ESP32-S3 IO USB-C | USB cable, /dev/esp32-io |
 
-Setup: `ip link set can0 up type can bitrate 500000`
+- Device node: `/dev/esp32-io` (udev symlink)
+- Baud: 460800, 8N1
+- Protocol: Binary frames `[0xAA][LEN][TYPE][PAYLOAD][CRC8]`
+- Use: IO expansion, GPIO control, sensor polling
 
-### 2. ESP32-S3 BALANCE ↔ CAN Bus
+### 4. ESP32-S3 BALANCE <-> VESC Motors (CAN Bus)
 
-| Signal | GPIO | CAN bus |
-|--------|------|---------|
-| CAN TX | TBD | → SN65HVD230 D pin |
-| CAN RX | TBD | ← SN65HVD230 R pin |
+| BALANCE Pin | Signal | VESC Pin | Notes |
+|-------------|--------|----------|-------|
+| GPIO21 | CAN-H | CAN-H | ISO 11898 differential pair |
+| GPIO22 | CAN-L | CAN-L | ISO 11898 differential pair |
+| GND | GND | GND | Common ground |
 
-> TBD pins — confirm in `esp32/balance/src/config.h`
+- Baud: 500 kbps CAN
+- VESC Left: CAN ID 56, VESC Right: CAN ID 68
+- Commands: COMM_SET_RPM, COMM_SET_CURRENT, COMM_SET_DUTY
+- Telemetry: VESC Status 1 at 50 Hz (RPM, current, duty)
 
-### 3. ESP32-S3 BALANCE ↔ ESP32-S3 IO (Inter-Board UART)
-
-| Signal | BALANCE GPIO | IO GPIO | Baud |
-|--------|-------------|---------|------|
-| TX | TBD | TBD (RX) | 460800 |
-| RX | TBD (RX) | TBD (TX) | 460800 |
-| GND | GND | GND | — |
-
-Frame: `[0xAA][LEN][TYPE][PAYLOAD…][CRC8]` — see `esp32/shared/protocol.h`
-
-### 4. ESP32-S3 IO ↔ TBS Crossfire RX (UART0)
-
-| IO GPIO | Signal | Crossfire pin | Notes |
-|---------|--------|---------------|-------|
-| GPIO43 | TX | RX | CRSF telemetry to TX module |
-| GPIO44 | RX | TX | CRSF RC frames in |
-| GND | GND | GND | |
-| 5V | — | VCC | Power from 5V bus |
-
-Baud: 420000 (CRSF). Failsafe: disarm after 300 ms without frame.
-
-### 5. ESP32-S3 IO ↔ ELRS Receiver (UART2, failover)
-
-| IO GPIO | Signal | ELRS pin |
-|---------|--------|----------|
-| TBD | TX | RX |
-| TBD | RX | TX |
-| GND | GND | GND |
-| 5V | — | VCC |
-
-Baud: 420000 (CRSF). Activates automatically if Crossfire link lost >300 ms.
-
-### 6. ESP32-S3 IO ↔ BTS7960 Motor Drivers (4×)
-
-TBD GPIO assignments — see `esp32/io/src/config.h`.
-
-| Signal | Per-driver | Notes |
-|--------|-----------|-------|
-| RPWM | GPIO TBD | Forward PWM |
-| LPWM | GPIO TBD | Reverse PWM |
-| R_EN | GPIO TBD | Enable H |
-| L_EN | GPIO TBD | Enable H |
-| Motor+ / Motor− | Hub motor | 36V via B+ / B− on BTS7960 |
-
-### 7. ESP32-S3 IO I2C Sensors
-
-| Device | I2C Address | Notes |
-|--------|-------------|-------|
-| NFC (PN532) | 0x24 | NFC tag read/write |
-| Barometer (BMP280/388) | 0x76 | Altitude + temp |
-| ToF range (VL53L0X) | 0x29 | Proximity/obstacle |
-
-> SDA / SCL GPIOs TBD — confirm in `esp32/io/src/config.h`
-
-### 8. Power Distribution
+### 5. Power Distribution
 
 ```
-36V BATTERY
+BATTERY (36V) ──┬── VESC Left  (36V direct -> BLDC left motor)
+                ├── VESC Right (36V direct -> BLDC right motor)
                 │
-  ├── VESC left  (36V) ─── Front-left + Rear-left hub motors
-  ├── VESC right (36V) ─── Front-right + Rear-right hub motors
-  ├── BTS7960 boards (B+/B−) — 36V motor power
+                ├── 5V BEC/regulator ──┬── Orin (USB-C PD or barrel jack)
+                │                      ├── ESP32-S3 BALANCE (5V via USB-C)
+                │                      ├── ESP32-S3 IO (5V via USB-C)
+                │                      ├── WS2812B LEDs (5V)
+                │                      └── RPLIDAR (5V via USB)
                 │
-  ├── DC-DC 12V ──── Fan / Headlight / Accessories
-  │
-  └── DC-DC 5V ─┬── Jetson Orin (USB-C PD)
-                 ├── ESP32-S3 BALANCE (USB 5V)
-                 ├── ESP32-S3 IO (USB 5V)
-                 ├── TBS Crossfire RX (5V)
-                 ├── ELRS RX (5V)
-                 ├── WS2812B strip (5V)
-                 ├── RPLIDAR A1M8 (5V via USB)
-                 └── Sensors (3.3V from ESP32-IO LDO)
+                └── Battery monitor ──── ESP32-S3 BALANCE ADC (voltage divider)
 ```
 
----
+### 6. Sensors on Orin (USB/CSI)
 
-## Orin USB Peripherals
+| Device | Interface | Orin Port | Device Node |
+|--------|-----------|-----------|-------------|
+| RealSense D435i | USB 3.1 | USB-A (blue) | `/dev/bus/usb/...` |
+| RPLIDAR A1M8 | USB-UART | USB-A | `/dev/rplidar` |
+| IMX219 front+left | MIPI CSI-2 | CSI-A (J5) | `/dev/video0,2` |
+| IMX219 rear+right | MIPI CSI-2 | CSI-B (J8) | `/dev/video4,6` |
+| 1TB NVMe | PCIe Gen3 x4 | M.2 Key M | `/dev/nvme0n1` |
+| CANable2 | USB-CAN | USB-A | `/dev/canable2` -> `slcan0` |
 
-| Device | Interface | Node |
-|--------|-----------|------|
-| CANable 2.0 | USB-A | `can0` (after `ip link set can0 up type can bitrate 500000`) |
-| RealSense D435i | USB 3.1 | `/dev/bus/usb/...` |
-| RPLIDAR A1M8 | USB-UART | `/dev/rplidar` |
-| SIM7600A 4G | USB | `/dev/ttyUSB0–2` |
-| ESP32-S3 BALANCE debug | USB-A (CH343) | `/dev/esp32-balance` |
-| ESP32-S3 IO debug | USB-A (JTAG/CDC) | `/dev/esp32-io` |
 
----
+<<<<<<< HEAD
+## FC UART Summary (MAMBA F722S — OBSOLETE)
 
-## ReSpeaker 2-Mic HAT (Orin 40-pin)
+| Interface | Pins | Baud/Rate | Assignment | Notes |
+|-----------|------|-----------|------------|-------|
+| UART0 | GPIO17=RX, GPIO18=TX | 460800 | Orin UART fallback | 3.3V, cross-connect |
+| UART1 | GPIO19=RX, GPIO20=TX | 115200 | Debug serial | Optional |
+| CAN (TWAI) | GPIO21=H, GPIO22=L | 500 kbps | CAN bus (VESCs + Orin) | SN65HVD230 transceiver |
+| I2C | GPIO4=SDA, GPIO5=SCL | 400 kHz | QMI8658 IMU (addr 0x6B) | Onboard |
+| SPI | GPIO36=MOSI, GPIO37=SCLK, GPIO35=CS | 40 MHz | GC9A01 LCD (onboard) | 240x240 round |
+| USB CDC | USB-C | 460800 | Orin USB fallback | /dev/esp32-balance |
+
+## CAN Frame ID Map
+
+| CAN ID | Direction | Name | Contents |
+|--------|-----------|------|----------|
+| 0x300 | Orin -> BALANCE | ORIN_CMD_DRIVE | left_rpm_f32, right_rpm_f32 (8 bytes LE) |
+| 0x301 | Orin -> BALANCE | ORIN_CMD_MODE | mode byte (0=IDLE, 1=DRIVE, 2=ESTOP) |
+| 0x302 | Orin -> BALANCE | ORIN_CMD_ESTOP | flags byte (bit0=stop, bit1=clear) |
+| 0x400 | BALANCE -> Orin | BALANCE_STATUS | pitch x10:i16, motor_cmd:u16, vbat_mv:u16, state:u8, flags:u8 |
+| 0x401 | BALANCE -> Orin | BALANCE_VESC | l_rpm x10:i16, r_rpm x10:i16, l_cur x10:i16, r_cur x10:i16 |
+| 0x402 | BALANCE -> Orin | BALANCE_IMU | pitch x100:i16, roll x100:i16, yaw x100:i16, ax x100:i16, ay x100:i16, az x100:i16 |
+| 0x403 | BALANCE -> Orin | BALANCE_BATTERY | vbat_mv:u16, current_ma:i16, soc_pct:u8 |
+| 0x900+ID | VESC Left -> | VESC_STATUS_1 | erpm:i32, current x10:i16, duty x1000:i16 |
+| 0x910+ID | VESC Right -> | VESC_STATUS_1 | erpm:i32, current x10:i16, duty x1000:i16 |
+
+VESC Left CAN ID = 56 (0x38), VESC Right CAN ID = 68 (0x44).
+=======
+## FC UART Summary (ESP32-S3 BALANCE)
+
+| UART | Pins | Baud | Assignment | Notes |
+|------|------|------|------------|-------|
+| USART1 | PB6=TX, PB7=RX | — | SmartAudio/VTX | Unused in SaltyLab |
+| USART2 | PA2=TX, PA3=RX | 26400 | Hoverboard ESC | Binary motor commands |
+| USART3 | PB10=TX, PB11=RX | — | Available | Was SBUS default |
+| UART4 | PA0=TX, PA1=RX | 420000 | ELRS RX (CRSF) | RC control |
+| UART5 | PC12=TX, PD2=RX | 115200 | Debug serial | Optional |
+| USART6 | PC6=TX, PC7=RX | 921600 | Jetson UART | Fallback link |
+| USB Serial (CH343) | USB-C | 921600 | Jetson primary | `/dev/esp32-bridge` |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+
+### 7. ReSpeaker 2-Mic HAT (on Orin 40-pin header)
 
 | Orin Pin | Signal | Function |
 |----------|--------|----------|
@@ -176,20 +214,117 @@ TBD GPIO assignments — see `esp32/io/src/config.h`.
 | Pin 35 (GPIO 19) | I2S LRCLK | Audio left/right clock |
 | Pin 38 (GPIO 20) | I2S DIN | Audio data in (from mics) |
 | Pin 40 (GPIO 21) | I2S DOUT | Audio data out (to speaker) |
-| Pin 3 (GPIO 2) | I2C SDA | WM8960 codec (i2c-7) |
-| Pin 5 (GPIO 3) | I2C SCL | WM8960 codec (i2c-7) |
+| Pin 3 (GPIO 2) | I2C SDA | WM8960 codec control (i2c-7) |
+| Pin 5 (GPIO 3) | I2C SCL | WM8960 codec control (i2c-7) |
+| Pin 32 (GPIO 12) | GPIO | Button input |
+| Pin 11 (GPIO 17) | GPIO | RGB LED (APA102 data) |
 | Pin 2, 4 | 5V | Power |
 | Pin 6, 9 | GND | Ground |
 
-Codec: Wolfson WM8960 (0x1A). Use: voice commands, wake word, audio feedback.
+- Codec: Wolfson WM8960 (I2C addr 0x1A)
+- Mics: 2x MEMS (left + right) --- basic stereo / sound localization
+- Speaker: 3W class-D amp output (JST connector)
+- Headset: 3.5mm TRRS jack
+- Requires: WM8960 device tree overlay for Jetson (community port)
+- Use: Voice commands (faster-whisper), wake word (openWakeWord), audio feedback, status announcements
 
----
-
-## SIM7600A 4G/LTE HAT (Orin USB)
+### 8. SIM7600A 4G/LTE HAT (via USB)
 
 | Connection | Detail |
 |-----------|--------|
-| Interface | USB (micro-B on HAT → USB-A on Orin) |
+| Interface | USB (micro-B on HAT -> USB-A/C on Orin) |
 | Device nodes | `/dev/ttyUSB0` (AT), `/dev/ttyUSB1` (PPP/data), `/dev/ttyUSB2` (GPS NMEA) |
-| Power | 5V from USB (peak 2A during TX) |
-| SIM | Nano-SIM slot |
+| Power | 5V from USB or separate 5V supply (peak 2A during TX) |
+| SIM | Nano-SIM slot on HAT |
+| Antenna | 4G LTE + GPS/GNSS (external SMA antennas --- mount high on chassis) |
+
+- Data: PPP or QMI for internet connectivity
+- GPS/GNSS: Built-in receiver, NMEA sentences on ttyUSB2 --- outdoor positioning
+- AT commands: `AT+CGPS=1` (enable GPS), `AT+CGPSINFO` (get fix)
+- Connected via USB (not 40-pin) --- avoids UART conflict with BALANCE fallback, flexible antenna placement
+- Use: Remote telemetry, 4G connectivity outdoors, GPS positioning, remote SSH/control
+
+### 9. Leap Motion Controller (USB)
+
+| Connection | Detail |
+|-----------|--------|
+| Interface | USB 3.0 (micro-B on controller -> USB-A on Orin) |
+| Power | ~0.5W |
+| Range | ~80cm, 150 deg FOV |
+| SDK | Ultraleap Gemini V5+ (Linux ARM64 support) |
+| ROS2 | `leap_motion_ros2` wrapper available |
+
+- 2x IR cameras + 3x IR LEDs --- tracks all 10 fingers in 3D, sub-mm precision
+- Mount: Forward-facing on sensor tower or upward on Orin plate
+- Use: Gesture control (palm=stop, point=go, fist=arm), hand-following mode, demos
+- Combined with ReSpeaker: Voice + gesture control with zero hardware in hand
+
+### 10. Power Budget (USB)
+
+| Device | Interface | Power Draw |
+|--------|-----------|------------|
+<<<<<<< HEAD
+| CANable2 USB-CAN | USB-A | ~0.5W |
+| ESP32-S3 BALANCE | USB-C | ~0.8W (WiFi off) |
+| ESP32-S3 IO | USB-C | ~0.5W |
+=======
+| ESP32-S3 FC (CDC) | USB-C | ~0.5W (data only, FC on 5V bus) |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+| RealSense D435i | USB-A | ~1.5W (3.5W peak) |
+| RPLIDAR A1M8 | USB-A | ~2.6W (motor on) |
+| SIM7600A | USB | ~1W idle, 3W TX peak |
+| Leap Motion | USB-A | ~0.5W |
+| ReSpeaker HAT | 40-pin | ~0.5W |
+| **Total USB** | | **~7.9W typical, ~11W peak** |
+
+Orin Nano Super delivers up to 25W --- USB peripherals are well within budget.
+
+---
+
+## Data Flow
+
+```
+                    ┌──────────────┐
+                    │  RC TX       │ (in your hand)
+                    │  (2.4GHz)    │
+                    └──────┬───────┘
+                           │ radio
+                    ┌──────▼───────┐
+                    │  RC RX       │ CRSF 420kbaud (future)
+                    └──────┬───────┘
+                           │ UART
+              ┌────────────▼────────────┐
+<<<<<<< HEAD
+              │   ESP32-S3 BALANCE      │
+              │  (Waveshare LCD 1.28)   │
+=======
+              │      ESP32-S3 BALANCE        │
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+              │                         │
+              │  QMI8658 -> Balance PID │
+              │  RC -> Mode Manager     │
+              │  Safety Monitor         │
+              │                         │
+              └──┬──────────┬───────────┘
+<<<<<<< HEAD
+    CAN 500kbps─┘          └───── CAN bus / UART fallback
+=======
+    USART2 ─────┘          └───── USB Serial (CH343) / USART6
+    26400 baud                    921600 baud
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+         │                              │
+    ┌────┴────────────┐                 ▼
+    │ CAN bus (500k)  │        ┌───────────────────┐
+    ├─ VESC Left  56  │        │   Orin Nano Super  │
+    └─ VESC Right 68  │        │                     │
+         │    │                │  SLAM / Nav2 / AI  │
+         ▼    ▼                │  Person following   │
+       LEFT  RIGHT             │  Voice commands     │
+       MOTOR MOTOR             │  4G telemetry       │
+                               └──┬──────────┬───────┘
+                                  │          │
+                       ┌──────────▼─┐   ┌────▼──────────┐
+                       │ ReSpeaker  │   │  SIM7600A     │
+                       │ 2-Mic HAT  │   │  4G/LTE + GPS │
+                       └────────────┘   └───────────────┘
+```

esp32s3/balance/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.16)
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(esp32s3_balance)

esp32s3/balance/main/CMakeLists.txt

@@ -0,0 +1,23 @@
+idf_component_register(
+    SRCS
+        "main.c"
+        "orin_serial.c"
+        "vesc_can.c"
+        "gc9a01.c"
+        "gitea_ota.c"
+        "ota_self.c"
+        "uart_ota.c"
+        "ota_display.c"
+    INCLUDE_DIRS "."
+    REQUIRES
+        esp_wifi
+        esp_http_client
+        esp_https_ota
+        nvs_flash
+        app_update
+        mbedtls
+        espressif__cjson
+        driver
+        freertos
+        esp_timer
+)

esp32s3/balance/main/config.h

@@ -0,0 +1,50 @@
+#pragma once
+
+/* ── ESP32-S3 BALANCE board — Waveshare ESP32-S3-Touch-LCD-1.28 pinout ─────
+ *
+ * Orin comms:  CH343 USB-to-serial on UART0 (GPIO43/44) → /dev/ttyACM0 on Orin
+ * VESC CAN:    SN65HVD230 transceiver on GPIO15 (TX) / GPIO16 (RX)
+ * Display:     GC9A01 on SPI2 — BL=GPIO40, RST=GPIO12
+ *
+ * GPIO2 is NOT used for CAN — it is free. Earlier versions had an erroneous
+ * conflict between DISP_BL (GPIO2) and VESC_CAN_TX (GPIO2); corrected here
+ * to match motor-test-firmware verified hardware layout (commit 8e66430).
+ */
+
+/* ── Orin serial (CH343 USB-to-UART, 1a86:55d3 on Orin side) ── */
+#define ORIN_UART_PORT          UART_NUM_0
+#define ORIN_UART_BAUD          460800
+#define ORIN_UART_TX_GPIO       43      /* ESP32 UART0 TX → CH343 RXD */
+#define ORIN_UART_RX_GPIO       44      /* CH343 TXD → ESP32 UART0 RX */
+#define ORIN_UART_RX_BUF        1024
+#define ORIN_TX_QUEUE_DEPTH     16
+
+/* ── Inter-board UART (ESP32 BALANCE ↔ ESP32 IO) ── */
+#define IO_UART_TX_GPIO         17
+#define IO_UART_RX_GPIO         18
+
+/* ── VESC CAN TWAI (SN65HVD230 on Waveshare header GPIO15/16) ── */
+#define VESC_CAN_TX_GPIO        15      /* ESP32 TWAI TX → SN65HVD230 TXD */
+#define VESC_CAN_RX_GPIO        16      /* SN65HVD230 RXD → ESP32 TWAI RX */
+#define VESC_CAN_RX_QUEUE       32
+
+/* VESC node IDs */
+#define VESC_ID_A               61u     /* FRONT VESC — drive + telemetry (0x81) */
+#define VESC_ID_B               79u     /* REAR  VESC — telemetry only    (0x82) */
+
+/* ── GC9A01 240×240 round display (Waveshare ESP32-S3-Touch-LCD-1.28, SPI2) ── */
+#define DISP_DC_GPIO     8
+#define DISP_CS_GPIO     9
+#define DISP_SCK_GPIO   10
+#define DISP_MOSI_GPIO  11
+#define DISP_RST_GPIO   12
+#define DISP_BL_GPIO    40
+
+/* ── Safety / timing ── */
+#define HB_TIMEOUT_MS           500u    /* heartbeat watchdog: disarm if exceeded */
+#define DRIVE_TIMEOUT_MS        500u    /* drive command staleness timeout */
+#define TELEM_STATUS_PERIOD_MS  100u    /* 10 Hz status telemetry to Orin */
+#define TELEM_VESC_PERIOD_MS    100u    /* 10 Hz VESC telemetry to Orin */
+
+/* ── Drive → VESC RPM scaling ── */
+#define RPM_PER_SPEED_UNIT      5       /* speed_units=1000 → 5000 ERPM */

esp32s3/balance/main/gc9a01.c

@@ -0,0 +1,269 @@
+/* gc9a01.c — GC9A01 240×240 round LCD SPI driver (bd-1yr8 display bead) */
+
+#include "gc9a01.h"
+#include "config.h"
+#include "driver/spi_master.h"
+#include "driver/gpio.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+#include <string.h>
+#include <math.h>
+
+static const char *TAG = "gc9a01";
+static spi_device_handle_t s_spi;
+
+/* ── 5×7 bitmap font, one byte per column (bit0 = top row), ASCII 32..126 ── */
+static const uint8_t s_font[95][5] = {
+    {0x00,0x00,0x00,0x00,0x00}, /* ' ' */  {0x00,0x00,0x5F,0x00,0x00}, /* '!' */
+    {0x00,0x07,0x00,0x07,0x00}, /* '"' */  {0x14,0x7F,0x14,0x7F,0x14}, /* '#' */
+    {0x24,0x2A,0x7F,0x2A,0x12}, /* '$' */  {0x23,0x13,0x08,0x64,0x62}, /* '%' */
+    {0x36,0x49,0x55,0x22,0x50}, /* '&' */  {0x00,0x05,0x03,0x00,0x00}, /* '\'' */
+    {0x00,0x1C,0x22,0x41,0x00}, /* '(' */  {0x00,0x41,0x22,0x1C,0x00}, /* ')' */
+    {0x14,0x08,0x3E,0x08,0x14}, /* '*' */  {0x08,0x08,0x3E,0x08,0x08}, /* '+' */
+    {0x00,0x50,0x30,0x00,0x00}, /* ',' */  {0x08,0x08,0x08,0x08,0x08}, /* '-' */
+    {0x00,0x60,0x60,0x00,0x00}, /* '.' */  {0x20,0x10,0x08,0x04,0x02}, /* '/' */
+    {0x3E,0x51,0x49,0x45,0x3E}, /* '0' */  {0x00,0x42,0x7F,0x40,0x00}, /* '1' */
+    {0x42,0x61,0x51,0x49,0x46}, /* '2' */  {0x21,0x41,0x45,0x4B,0x31}, /* '3' */
+    {0x18,0x14,0x12,0x7F,0x10}, /* '4' */  {0x27,0x45,0x45,0x45,0x39}, /* '5' */
+    {0x3C,0x4A,0x49,0x49,0x30}, /* '6' */  {0x01,0x71,0x09,0x05,0x03}, /* '7' */
+    {0x36,0x49,0x49,0x49,0x36}, /* '8' */  {0x06,0x49,0x49,0x29,0x1E}, /* '9' */
+    {0x00,0x36,0x36,0x00,0x00}, /* ':' */  {0x00,0x56,0x36,0x00,0x00}, /* ';' */
+    {0x08,0x14,0x22,0x41,0x00}, /* '<' */  {0x14,0x14,0x14,0x14,0x14}, /* '=' */
+    {0x00,0x41,0x22,0x14,0x08}, /* '>' */  {0x02,0x01,0x51,0x09,0x06}, /* '?' */
+    {0x32,0x49,0x79,0x41,0x3E}, /* '@' */  {0x7E,0x11,0x11,0x11,0x7E}, /* 'A' */
+    {0x7F,0x49,0x49,0x49,0x36}, /* 'B' */  {0x3E,0x41,0x41,0x41,0x22}, /* 'C' */
+    {0x7F,0x41,0x41,0x22,0x1C}, /* 'D' */  {0x7F,0x49,0x49,0x49,0x41}, /* 'E' */
+    {0x7F,0x09,0x09,0x09,0x01}, /* 'F' */  {0x3E,0x41,0x49,0x49,0x3A}, /* 'G' */
+    {0x7F,0x08,0x08,0x08,0x7F}, /* 'H' */  {0x00,0x41,0x7F,0x41,0x00}, /* 'I' */
+    {0x20,0x40,0x41,0x3F,0x01}, /* 'J' */  {0x7F,0x08,0x14,0x22,0x41}, /* 'K' */
+    {0x7F,0x40,0x40,0x40,0x40}, /* 'L' */  {0x7F,0x02,0x0C,0x02,0x7F}, /* 'M' */
+    {0x7F,0x04,0x08,0x10,0x7F}, /* 'N' */  {0x3E,0x41,0x41,0x41,0x3E}, /* 'O' */
+    {0x7F,0x09,0x09,0x09,0x06}, /* 'P' */  {0x3E,0x41,0x51,0x21,0x5E}, /* 'Q' */
+    {0x7F,0x09,0x19,0x29,0x46}, /* 'R' */  {0x46,0x49,0x49,0x49,0x31}, /* 'S' */
+    {0x01,0x01,0x7F,0x01,0x01}, /* 'T' */  {0x3F,0x40,0x40,0x40,0x3F}, /* 'U' */
+    {0x1F,0x20,0x40,0x20,0x1F}, /* 'V' */  {0x3F,0x40,0x38,0x40,0x3F}, /* 'W' */
+    {0x63,0x14,0x08,0x14,0x63}, /* 'X' */  {0x07,0x08,0x70,0x08,0x07}, /* 'Y' */
+    {0x61,0x51,0x49,0x45,0x43}, /* 'Z' */  {0x00,0x7F,0x41,0x41,0x00}, /* '[' */
+    {0x02,0x04,0x08,0x10,0x20}, /* '\\' */ {0x00,0x41,0x41,0x7F,0x00}, /* ']' */
+    {0x04,0x02,0x01,0x02,0x04}, /* '^' */  {0x40,0x40,0x40,0x40,0x40}, /* '_' */
+    {0x00,0x01,0x02,0x04,0x00}, /* '`' */  {0x20,0x54,0x54,0x54,0x78}, /* 'a' */
+    {0x7F,0x48,0x44,0x44,0x38}, /* 'b' */  {0x38,0x44,0x44,0x44,0x20}, /* 'c' */
+    {0x38,0x44,0x44,0x48,0x7F}, /* 'd' */  {0x38,0x54,0x54,0x54,0x18}, /* 'e' */
+    {0x08,0x7E,0x09,0x01,0x02}, /* 'f' */  {0x0C,0x52,0x52,0x52,0x3E}, /* 'g' */
+    {0x7F,0x08,0x04,0x04,0x78}, /* 'h' */  {0x00,0x44,0x7D,0x40,0x00}, /* 'i' */
+    {0x20,0x40,0x44,0x3D,0x00}, /* 'j' */  {0x7F,0x10,0x28,0x44,0x00}, /* 'k' */
+    {0x00,0x41,0x7F,0x40,0x00}, /* 'l' */  {0x7C,0x04,0x18,0x04,0x78}, /* 'm' */
+    {0x7C,0x08,0x04,0x04,0x78}, /* 'n' */  {0x38,0x44,0x44,0x44,0x38}, /* 'o' */
+    {0x7C,0x14,0x14,0x14,0x08}, /* 'p' */  {0x08,0x14,0x14,0x18,0x7C}, /* 'q' */
+    {0x7C,0x08,0x04,0x04,0x08}, /* 'r' */  {0x48,0x54,0x54,0x54,0x20}, /* 's' */
+    {0x04,0x3F,0x44,0x40,0x20}, /* 't' */  {0x3C,0x40,0x40,0x20,0x7C}, /* 'u' */
+    {0x1C,0x20,0x40,0x20,0x1C}, /* 'v' */  {0x3C,0x40,0x30,0x40,0x3C}, /* 'w' */
+    {0x44,0x28,0x10,0x28,0x44}, /* 'x' */  {0x0C,0x50,0x50,0x50,0x3C}, /* 'y' */
+    {0x44,0x64,0x54,0x4C,0x44}, /* 'z' */  {0x00,0x08,0x36,0x41,0x00}, /* '{' */
+    {0x00,0x00,0x7F,0x00,0x00}, /* '|' */  {0x00,0x41,0x36,0x08,0x00}, /* '}' */
+    {0x10,0x08,0x08,0x10,0x08},             /* '~' */
+};
+
+/* ── Static buffers (internal SRAM → DMA-safe) ── */
+static uint8_t s_line_buf[240 * 2];
+static uint8_t s_char_buf[5 * 5 * 7 * 5 * 2]; /* max scale=5: 25×35×2 */
+
+/* ── Low-level SPI helpers ── */
+static void write_cmd(uint8_t cmd)
+{
+    gpio_set_level(DISP_DC_GPIO, 0);
+    spi_transaction_t t = { .length = 8, .flags = SPI_TRANS_USE_TXDATA };
+    t.tx_data[0] = cmd;
+    spi_device_polling_transmit(s_spi, &t);
+}
+
+static void write_bytes(const uint8_t *data, size_t len)
+{
+    if (!len) return;
+    gpio_set_level(DISP_DC_GPIO, 1);
+    spi_transaction_t t = { .length = len * 8, .tx_buffer = data };
+    spi_device_polling_transmit(s_spi, &t);
+}
+
+static inline void write_byte(uint8_t b)  { write_bytes(&b, 1); }
+
+/* ── Address window ── */
+static void set_window(int x1, int y1, int x2, int y2)
+{
+    uint8_t d[4];
+    d[0] = x1 >> 8; d[1] = x1 & 0xFF; d[2] = x2 >> 8; d[3] = x2 & 0xFF;
+    write_cmd(0x2A); write_bytes(d, 4);
+    d[0] = y1 >> 8; d[1] = y1 & 0xFF; d[2] = y2 >> 8; d[3] = y2 & 0xFF;
+    write_cmd(0x2B); write_bytes(d, 4);
+}
+
+/* ── GC9A01 register init ── */
+static void init_regs(void)
+{
+    write_cmd(0xEF);
+    write_cmd(0xEB); write_byte(0x14);
+    write_cmd(0xFE);
+    write_cmd(0xEF);
+    write_cmd(0xEB); write_byte(0x14);
+    write_cmd(0x84); write_byte(0x40);
+    write_cmd(0x85); write_byte(0xFF);
+    write_cmd(0x86); write_byte(0xFF);
+    write_cmd(0x87); write_byte(0xFF);
+    write_cmd(0x88); write_byte(0x0A);
+    write_cmd(0x89); write_byte(0x21);
+    write_cmd(0x8A); write_byte(0x00);
+    write_cmd(0x8B); write_byte(0x80);
+    write_cmd(0x8C); write_byte(0x01);
+    write_cmd(0x8D); write_byte(0x01);
+    write_cmd(0x8E); write_byte(0xFF);
+    write_cmd(0x8F); write_byte(0xFF);
+    { uint8_t d[] = {0x00,0x20}; write_cmd(0xB6); write_bytes(d,2); }
+    write_cmd(0x36); write_byte(0x08);   /* MADCTL: normal, BGR */
+    write_cmd(0x3A); write_byte(0x05);   /* COLMOD: 16-bit RGB565 */
+    { uint8_t d[] = {0x08,0x08,0x08,0x08}; write_cmd(0x90); write_bytes(d,4); }
+    write_cmd(0xBD); write_byte(0x06);
+    write_cmd(0xBC); write_byte(0x00);
+    { uint8_t d[] = {0x60,0x01,0x04}; write_cmd(0xFF); write_bytes(d,3); }
+    write_cmd(0xC3); write_byte(0x13);
+    write_cmd(0xC4); write_byte(0x13);
+    write_cmd(0xC9); write_byte(0x22);
+    write_cmd(0xBE); write_byte(0x11);
+    { uint8_t d[] = {0x10,0x0E}; write_cmd(0xE1); write_bytes(d,2); }
+    { uint8_t d[] = {0x21,0x0C,0x02}; write_cmd(0xDF); write_bytes(d,3); }
+    { uint8_t d[] = {0x45,0x09,0x08,0x08,0x26,0x2A}; write_cmd(0xF0); write_bytes(d,6); }
+    { uint8_t d[] = {0x43,0x70,0x72,0x36,0x37,0x6F}; write_cmd(0xF1); write_bytes(d,6); }
+    { uint8_t d[] = {0x45,0x09,0x08,0x08,0x26,0x2A}; write_cmd(0xF2); write_bytes(d,6); }
+    { uint8_t d[] = {0x43,0x70,0x72,0x36,0x37,0x6F}; write_cmd(0xF3); write_bytes(d,6); }
+    { uint8_t d[] = {0x1B,0x0B}; write_cmd(0xED); write_bytes(d,2); }
+    write_cmd(0xAE); write_byte(0x77);
+    write_cmd(0xCD); write_byte(0x63);
+    { uint8_t d[] = {0x07,0x07,0x04,0x0E,0x0F,0x09,0x07,0x08,0x03};
+      write_cmd(0x70); write_bytes(d,9); }
+    write_cmd(0xE8); write_byte(0x34);
+    { uint8_t d[] = {0x18,0x0D,0xB7,0x18,0x0D,0x8B,0x88,0x08};
+      write_cmd(0x62); write_bytes(d,8); }
+    { uint8_t d[] = {0x18,0x0D,0xB7,0x58,0x1E,0x0B,0x00,0xA7,0x88,0x08};
+      write_cmd(0x63); write_bytes(d,10); }
+    { uint8_t d[] = {0x20,0x07,0x04}; write_cmd(0x64); write_bytes(d,3); }
+    { uint8_t d[] = {0x10,0x85,0x80,0x00,0x00,0x4E,0x00};
+      write_cmd(0x74); write_bytes(d,7); }
+    { uint8_t d[] = {0x3E,0x07}; write_cmd(0x98); write_bytes(d,2); }
+    write_cmd(0x35);           /* TEON */
+    write_cmd(0x21);           /* INVON */
+    write_cmd(0x11);           /* SLPOUT */
+    vTaskDelay(pdMS_TO_TICKS(120));
+    write_cmd(0x29);           /* DISPON */
+    vTaskDelay(pdMS_TO_TICKS(20));
+}
+
+/* ── Public init ── */
+void gc9a01_init(void)
+{
+    /* SPI bus */
+    spi_bus_config_t bus = {
+        .mosi_io_num     = DISP_MOSI_GPIO,
+        .miso_io_num     = -1,
+        .sclk_io_num     = DISP_SCK_GPIO,
+        .quadwp_io_num   = -1,
+        .quadhd_io_num   = -1,
+        .max_transfer_sz = 4096,
+    };
+    ESP_ERROR_CHECK(spi_bus_initialize(SPI2_HOST, &bus, SPI_DMA_CH_AUTO));
+
+    spi_device_interface_config_t dev = {
+        .clock_speed_hz = 40 * 1000 * 1000,
+        .mode           = 0,
+        .spics_io_num   = DISP_CS_GPIO,
+        .queue_size     = 1,
+    };
+    ESP_ERROR_CHECK(spi_bus_add_device(SPI2_HOST, &dev, &s_spi));
+
+    /* DC, RST, BL GPIOs */
+    gpio_set_direction(DISP_DC_GPIO,  GPIO_MODE_OUTPUT);
+    gpio_set_direction(DISP_RST_GPIO, GPIO_MODE_OUTPUT);
+    gpio_set_direction(DISP_BL_GPIO,  GPIO_MODE_OUTPUT);
+
+    /* Hardware reset */
+    gpio_set_level(DISP_RST_GPIO, 0); vTaskDelay(pdMS_TO_TICKS(10));
+    gpio_set_level(DISP_RST_GPIO, 1); vTaskDelay(pdMS_TO_TICKS(120));
+
+    init_regs();
+
+    /* Backlight on */
+    gpio_set_level(DISP_BL_GPIO, 1);
+    ESP_LOGI(TAG, "GC9A01 init OK: DC=%d CS=%d SCK=%d MOSI=%d RST=%d BL=%d",
+             DISP_DC_GPIO, DISP_CS_GPIO, DISP_SCK_GPIO, DISP_MOSI_GPIO,
+             DISP_RST_GPIO, DISP_BL_GPIO);
+}
+
+/* ── display_fill_rect ── */
+void display_fill_rect(int x, int y, int w, int h, uint16_t rgb565)
+{
+    if (w <= 0 || h <= 0) return;
+    if (x < 0) { w += x; x = 0; }
+    if (y < 0) { h += y; y = 0; }
+    if (x + w > 240) w = 240 - x;
+    if (y + h > 240) h = 240 - y;
+    if (w <= 0 || h <= 0) return;
+
+    set_window(x, y, x + w - 1, y + h - 1);
+    write_cmd(0x2C);
+
+    uint8_t hi = rgb565 >> 8, lo = rgb565 & 0xFF;
+    for (int i = 0; i < w * 2; i += 2) { s_line_buf[i] = hi; s_line_buf[i+1] = lo; }
+    for (int row = 0; row < h; row++) { write_bytes(s_line_buf, (size_t)(w * 2)); }
+}
+
+/* ── Glyph rasteriser (handles scale 1..5) ── */
+static void draw_char_s(int x, int y, char c, uint16_t fg, uint16_t bg, int scale)
+{
+    if ((uint8_t)c < 32 || (uint8_t)c > 126) return;
+    if (scale < 1) scale = 1;
+    if (scale > 5) scale = 5;
+    const uint8_t *g = s_font[(uint8_t)c - 32];
+    int cw = 5 * scale, ch = 7 * scale;
+
+    uint8_t *p = s_char_buf;
+    for (int row = 0; row < 7; row++) {
+        for (int sr = 0; sr < scale; sr++) {
+            for (int col = 0; col < 5; col++) {
+                uint16_t color = ((g[col] >> row) & 1) ? fg : bg;
+                uint8_t hi = color >> 8, lo = color & 0xFF;
+                for (int sc = 0; sc < scale; sc++) { *p++ = hi; *p++ = lo; }
+            }
+        }
+    }
+    set_window(x, y, x + cw - 1, y + ch - 1);
+    write_cmd(0x2C);
+    write_bytes(s_char_buf, (size_t)(cw * ch * 2));
+}
+
+/* ── display_draw_string / display_draw_string_s ── */
+void display_draw_string(int x, int y, const char *str, uint16_t fg, uint16_t bg)
+{
+    display_draw_string_s(x, y, str, fg, bg, 1);
+}
+
+void display_draw_string_s(int x, int y, const char *str,
+                           uint16_t fg, uint16_t bg, int scale)
+{
+    int cx = x;
+    while (*str) {
+        draw_char_s(cx, y, *str++, fg, bg, scale);
+        cx += 6 * scale;
+    }
+}
+
+/* ── display_draw_arc ── */
+void display_draw_arc(int cx, int cy, int r, int start_deg, int end_deg,
+                      int thickness, uint16_t color)
+{
+    for (int deg = start_deg; deg <= end_deg; deg++) {
+        float rad = (float)deg * (3.14159265f / 180.0f);
+        int px = cx + (int)((float)r * cosf(rad));
+        int py = cy + (int)((float)r * sinf(rad));
+        int half = thickness / 2;
+        display_fill_rect(px - half, py - half, thickness, thickness, color);
+    }
+}

esp32s3/balance/main/gc9a01.h

@@ -0,0 +1,24 @@
+#pragma once
+/* gc9a01.h — GC9A01 240×240 round LCD SPI driver (bd-1yr8 display bead) */
+
+#include <stdint.h>
+
+/* ── Initialise SPI bus + GC9A01. Call once from app_main. ── */
+void gc9a01_init(void);
+
+/* ── Display primitives (also satisfy ota_display.h contract) ── */
+void display_fill_rect(int x, int y, int w, int h, uint16_t rgb565);
+void display_draw_string(int x, int y, const char *str, uint16_t fg, uint16_t bg);
+void display_draw_string_s(int x, int y, const char *str,
+                           uint16_t fg, uint16_t bg, int scale);
+void display_draw_arc(int cx, int cy, int r,
+                      int start_deg, int end_deg, int thickness, uint16_t color);
+
+/* ── Colour palette (RGB565) ── */
+#define COL_BG     0x0000u
+#define COL_WHITE  0xFFFFu
+#define COL_GREEN  0x07E0u
+#define COL_YELLOW 0xFFE0u
+#define COL_RED    0xF800u
+#define COL_BLUE   0x001Fu
+#define COL_ORANGE 0xFD20u

esp32s3/balance/main/gitea_ota.c

@@ -0,0 +1,285 @@
+/* gitea_ota.c — Gitea version checker (bd-3hte)
+ *
+ * Uses esp_http_client + cJSON to query:
+ *   GET /api/v1/repos/{repo}/releases?limit=10
+ * Filters releases by tag prefix, extracts version and download URLs.
+ */
+
+#include "gitea_ota.h"
+#include "version.h"
+#include "esp_log.h"
+#include "esp_wifi.h"
+#include "esp_event.h"
+#include "esp_netif.h"
+#include "esp_http_client.h"
+#include "nvs_flash.h"
+#include "nvs.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/event_groups.h"
+#include "cJSON.h"
+#include <string.h>
+#include <stdio.h>
+
+static const char *TAG = "gitea_ota";
+
+ota_update_info_t g_balance_update = {0};
+ota_update_info_t g_io_update      = {0};
+
+/* ── WiFi connection ── */
+#define WIFI_CONNECTED_BIT  BIT0
+#define WIFI_FAIL_BIT       BIT1
+#define WIFI_MAX_RETRIES    5
+
+/* Compile-time WiFi fallback (override in NVS "wifi"/"ssid","pass") */
+#define DEFAULT_WIFI_SSID   "saltylab"
+#define DEFAULT_WIFI_PASS   ""
+
+static EventGroupHandle_t s_wifi_eg;
+static int s_wifi_retries = 0;
+
+static void wifi_event_handler(void *arg, esp_event_base_t base,
+                                int32_t id, void *data)
+{
+    if (base == WIFI_EVENT && id == WIFI_EVENT_STA_START) {
+        esp_wifi_connect();
+    } else if (base == WIFI_EVENT && id == WIFI_EVENT_STA_DISCONNECTED) {
+        if (s_wifi_retries < WIFI_MAX_RETRIES) {
+            esp_wifi_connect();
+            s_wifi_retries++;
+        } else {
+            xEventGroupSetBits(s_wifi_eg, WIFI_FAIL_BIT);
+        }
+    } else if (base == IP_EVENT && id == IP_EVENT_STA_GOT_IP) {
+        s_wifi_retries = 0;
+        xEventGroupSetBits(s_wifi_eg, WIFI_CONNECTED_BIT);
+    }
+}
+
+static bool wifi_connect(void)
+{
+    char ssid[64] = DEFAULT_WIFI_SSID;
+    char pass[64] = DEFAULT_WIFI_PASS;
+
+    /* Try to read credentials from NVS */
+    nvs_handle_t nvs;
+    if (nvs_open("wifi", NVS_READONLY, &nvs) == ESP_OK) {
+        size_t sz = sizeof(ssid);
+        nvs_get_str(nvs, "ssid", ssid, &sz);
+        sz = sizeof(pass);
+        nvs_get_str(nvs, "pass", pass, &sz);
+        nvs_close(nvs);
+    }
+
+    s_wifi_eg = xEventGroupCreate();
+    s_wifi_retries = 0;
+
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+    esp_netif_create_default_wifi_sta();
+
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+
+    esp_event_handler_instance_t h1, h2;
+    ESP_ERROR_CHECK(esp_event_handler_instance_register(
+        WIFI_EVENT, ESP_EVENT_ANY_ID, wifi_event_handler, NULL, &h1));
+    ESP_ERROR_CHECK(esp_event_handler_instance_register(
+        IP_EVENT, IP_EVENT_STA_GOT_IP, wifi_event_handler, NULL, &h2));
+
+    wifi_config_t wcfg = {0};
+    strlcpy((char *)wcfg.sta.ssid,     ssid, sizeof(wcfg.sta.ssid));
+    strlcpy((char *)wcfg.sta.password, pass, sizeof(wcfg.sta.password));
+
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wcfg));
+    ESP_ERROR_CHECK(esp_wifi_start());
+
+    EventBits_t bits = xEventGroupWaitBits(s_wifi_eg,
+        WIFI_CONNECTED_BIT | WIFI_FAIL_BIT, pdFALSE, pdFALSE,
+        pdMS_TO_TICKS(15000));
+
+    esp_event_handler_instance_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, h2);
+    esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, h1);
+    vEventGroupDelete(s_wifi_eg);
+
+    if (bits & WIFI_CONNECTED_BIT) {
+        ESP_LOGI(TAG, "WiFi connected SSID=%s", ssid);
+        return true;
+    }
+    ESP_LOGW(TAG, "WiFi connect failed SSID=%s", ssid);
+    return false;
+}
+
+/* ── HTTP fetch into a heap buffer ── */
+#define HTTP_RESP_MAX   (8 * 1024)
+
+typedef struct { char *buf; int len; int cap; } http_buf_t;
+
+static esp_err_t http_event_cb(esp_http_client_event_t *evt)
+{
+    http_buf_t *b = (http_buf_t *)evt->user_data;
+    if (evt->event_id == HTTP_EVENT_ON_DATA && b) {
+        if (b->len + evt->data_len < b->cap) {
+            memcpy(b->buf + b->len, evt->data, evt->data_len);
+            b->len += evt->data_len;
+        }
+    }
+    return ESP_OK;
+}
+
+static char *http_get(const char *url)
+{
+    char *buf = malloc(HTTP_RESP_MAX);
+    if (!buf) return NULL;
+    http_buf_t b = {.buf = buf, .len = 0, .cap = HTTP_RESP_MAX};
+    buf[0] = '\0';
+
+    esp_http_client_config_t cfg = {
+        .url            = url,
+        .event_handler  = http_event_cb,
+        .user_data      = &b,
+        .timeout_ms     = GITEA_API_TIMEOUT_MS,
+        .skip_cert_common_name_check = true,
+    };
+    esp_http_client_handle_t client = esp_http_client_init(&cfg);
+    esp_err_t err = esp_http_client_perform(client);
+    int status = esp_http_client_get_status_code(client);
+    esp_http_client_cleanup(client);
+
+    if (err != ESP_OK || status != 200) {
+        ESP_LOGW(TAG, "HTTP GET %s → err=%d status=%d", url, err, status);
+        free(buf);
+        return NULL;
+    }
+    buf[b.len] = '\0';
+    return buf;
+}
+
+/* ── Version comparison: returns true if remote > local ── */
+static bool version_newer(const char *local, const char *remote)
+{
+    int la=0,lb=0,lc=0, ra=0,rb=0,rc=0;
+    sscanf(local,  "%d.%d.%d", &la, &lb, &lc);
+    sscanf(remote, "%d.%d.%d", &ra, &rb, &rc);
+    if (ra != la) return ra > la;
+    if (rb != lb) return rb > lb;
+    return rc > lc;
+}
+
+/* ── Parse releases JSON array, fill ota_update_info_t ── */
+static void parse_releases(const char *json, const char *tag_prefix,
+                             const char *bin_asset, const char *sha_asset,
+                             const char *local_version,
+                             ota_update_info_t *out)
+{
+    cJSON *arr = cJSON_Parse(json);
+    if (!arr || !cJSON_IsArray(arr)) {
+        ESP_LOGW(TAG, "JSON parse failed");
+        cJSON_Delete(arr);
+        return;
+    }
+
+    cJSON *rel;
+    cJSON_ArrayForEach(rel, arr) {
+        cJSON *tag_j = cJSON_GetObjectItem(rel, "tag_name");
+        if (!cJSON_IsString(tag_j)) continue;
+
+        const char *tag = tag_j->valuestring;
+        if (strncmp(tag, tag_prefix, strlen(tag_prefix)) != 0) continue;
+
+        /* Extract version after prefix */
+        const char *ver = tag + strlen(tag_prefix);
+        if (*ver == 'v') ver++;  /* strip leading 'v' */
+
+        if (!version_newer(local_version, ver)) continue;
+
+        /* Found a newer release — extract asset URLs */
+        cJSON *assets = cJSON_GetObjectItem(rel, "assets");
+        if (!cJSON_IsArray(assets)) continue;
+
+        out->available = false;
+        out->download_url[0] = '\0';
+        out->sha256[0] = '\0';
+        strlcpy(out->version, ver, sizeof(out->version));
+
+        cJSON *asset;
+        cJSON_ArrayForEach(asset, assets) {
+            cJSON *name_j = cJSON_GetObjectItem(asset, "name");
+            cJSON *url_j  = cJSON_GetObjectItem(asset, "browser_download_url");
+            if (!cJSON_IsString(name_j) || !cJSON_IsString(url_j)) continue;
+
+            if (strcmp(name_j->valuestring, bin_asset) == 0) {
+                strlcpy(out->download_url, url_j->valuestring,
+                        sizeof(out->download_url));
+                out->available = true;
+            } else if (strcmp(name_j->valuestring, sha_asset) == 0) {
+                /* Download the SHA256 asset inline */
+                char *sha = http_get(url_j->valuestring);
+                if (sha) {
+                    /* sha file is just hex+newline */
+                    size_t n = strspn(sha, "0123456789abcdefABCDEF");
+                    if (n == 64) {
+                        memcpy(out->sha256, sha, 64);
+                        out->sha256[64] = '\0';
+                    }
+                    free(sha);
+                }
+            }
+        }
+
+        if (out->available) {
+            ESP_LOGI(TAG, "update: tag=%s ver=%s", tag, out->version);
+        }
+        break;  /* use first matching release */
+    }
+
+    cJSON_Delete(arr);
+}
+
+/* ── Main check ── */
+void gitea_ota_check_now(void)
+{
+    char url[512];
+    snprintf(url, sizeof(url),
+             "%s/api/v1/repos/%s/releases?limit=10",
+             GITEA_BASE_URL, GITEA_REPO);
+
+    char *json = http_get(url);
+    if (!json) {
+        ESP_LOGW(TAG, "releases fetch failed");
+        return;
+    }
+
+    parse_releases(json, BALANCE_TAG_PREFIX, BALANCE_BIN_ASSET,
+                   BALANCE_SHA256_ASSET, BALANCE_FW_VERSION, &g_balance_update);
+    parse_releases(json, IO_TAG_PREFIX, IO_BIN_ASSET,
+                   IO_SHA256_ASSET, IO_FW_VERSION, &g_io_update);
+    free(json);
+}
+
+/* ── Background task ── */
+static void version_check_task(void *arg)
+{
+    /* Initial check immediately after WiFi up */
+    vTaskDelay(pdMS_TO_TICKS(2000));
+    gitea_ota_check_now();
+
+    for (;;) {
+        vTaskDelay(pdMS_TO_TICKS(VERSION_CHECK_PERIOD_MS));
+        gitea_ota_check_now();
+    }
+}
+
+void gitea_ota_init(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+
+    if (!wifi_connect()) {
+        ESP_LOGW(TAG, "WiFi unavailable — version checks disabled");
+        return;
+    }
+
+    xTaskCreate(version_check_task, "ver_check", 6144, NULL, 3, NULL);
+    ESP_LOGI(TAG, "version check task started");
+}

esp32s3/balance/main/gitea_ota.h

@@ -0,0 +1,42 @@
+#pragma once
+/* gitea_ota.h — Gitea release version checker (bd-3hte)
+ *
+ * WiFi task: on boot and every 30 min, queries Gitea releases API,
+ * compares tag version against embedded FW_VERSION, stores update info.
+ *
+ * WiFi credentials read from NVS namespace "wifi" keys "ssid"/"pass".
+ * Fall back to compile-time defaults if NVS is empty.
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/* Gitea instance */
+#define GITEA_BASE_URL      "http://gitea.vayrette.com"
+#define GITEA_REPO          "seb/saltylab-firmware"
+#define GITEA_API_TIMEOUT_MS 10000
+
+/* Version check interval */
+#define VERSION_CHECK_PERIOD_MS  (30u * 60u * 1000u)  /* 30 minutes */
+
+/* Max URL/version string lengths */
+#define OTA_URL_MAX     384
+#define OTA_VER_MAX     32
+#define OTA_SHA256_MAX  65
+
+typedef struct {
+    bool    available;
+    char    version[OTA_VER_MAX];      /* remote version string, e.g. "1.2.3" */
+    char    download_url[OTA_URL_MAX]; /* direct download URL for .bin */
+    char    sha256[OTA_SHA256_MAX];    /* hex SHA256 (from .sha256 asset), or "" */
+} ota_update_info_t;
+
+/* Shared state — written by gitea_ota_check_task, read by display/OTA tasks */
+extern ota_update_info_t g_balance_update;
+extern ota_update_info_t g_io_update;
+
+/* Initialize WiFi and start version check task */
+void gitea_ota_init(void);
+
+/* One-shot sync check (can be called from any task) */
+void gitea_ota_check_now(void);

esp32s3/balance/main/idf_component.yml

@@ -0,0 +1,5 @@
+dependencies:
+  idf:
+    version: '>=5.0'
+  espressif/cjson:
+    version: "^1.7.19~2"

esp32s3/balance/main/main.c

@@ -0,0 +1,110 @@
+/* main.c — ESP32-S3 BALANCE app_main (bd-66hx + OTA beads) */
+
+#include "orin_serial.h"
+#include "vesc_can.h"
+#include "gc9a01.h"
+#include "gitea_ota.h"
+#include "ota_self.h"
+#include "uart_ota.h"
+#include "ota_display.h"
+#include "config.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/queue.h"
+#include "esp_log.h"
+#include "esp_timer.h"
+#include <string.h>
+
+static const char *TAG = "main";
+
+static QueueHandle_t s_orin_tx_q;
+
+/* ── Telemetry task: sends TELEM_STATUS to Orin at 10 Hz ── */
+static void telem_task(void *arg)
+{
+    for (;;) {
+        vTaskDelay(pdMS_TO_TICKS(TELEM_STATUS_PERIOD_MS));
+
+        uint32_t now_ms = (uint32_t)(esp_timer_get_time() / 1000LL);
+        bool hb_timeout = (now_ms - g_orin_ctrl.hb_last_ms) > HB_TIMEOUT_MS;
+
+        /* Determine balance state for telemetry */
+        bal_state_t state;
+        if (g_orin_ctrl.estop) {
+            state = BAL_ESTOP;
+        } else if (!g_orin_ctrl.armed) {
+            state = BAL_DISARMED;
+        } else {
+            state = BAL_ARMED;
+        }
+
+        /* flags: bit0=estop_active, bit1=heartbeat_timeout */
+        uint8_t flags = (g_orin_ctrl.estop ? 0x01u : 0x00u) |
+                        (hb_timeout         ? 0x02u : 0x00u);
+
+        /* Battery voltage from VESC_ID_A STATUS_5 (V×10 → mV) */
+        uint16_t vbat_mv = (uint16_t)((int32_t)g_vesc[0].voltage_x10 * 100);
+
+        orin_send_status(s_orin_tx_q,
+                         0,      /* pitch_x10: stub — full IMU in future bead */
+                         0,      /* motor_cmd: stub */
+                         vbat_mv,
+                         state,
+                         flags);
+    }
+}
+
+/* ── Drive task: applies Orin drive commands to VESCs @ 50 Hz ── */
+static void drive_task(void *arg)
+{
+    for (;;) {
+        vTaskDelay(pdMS_TO_TICKS(20));  /* 50 Hz */
+
+        uint32_t now_ms   = (uint32_t)(esp_timer_get_time() / 1000LL);
+        bool hb_timeout   = (now_ms - g_orin_ctrl.hb_last_ms) > HB_TIMEOUT_MS;
+        bool drive_stale  = (now_ms - g_orin_drive.updated_ms) > DRIVE_TIMEOUT_MS;
+
+        int32_t front_erpm = 0;
+
+        if (g_orin_ctrl.armed && !g_orin_ctrl.estop &&
+            !hb_timeout && !drive_stale) {
+            front_erpm = (int32_t)g_orin_drive.speed * RPM_PER_SPEED_UNIT;
+        }
+
+        vesc_can_send_rpm(VESC_ID_A, front_erpm);
+    }
+}
+
+void app_main(void)
+{
+    ESP_LOGI(TAG, "ESP32-S3 BALANCE starting");
+
+    /* OTA rollback health check — must be called within OTA_ROLLBACK_WINDOW_S */
+    ota_self_health_check();
+
+    /* Init peripherals — gc9a01 before vesc_can so BL/GPIO2 is high before TWAI takes it */
+    gc9a01_init();
+    orin_serial_init();
+    vesc_can_init();
+
+    /* TX queue for outbound serial frames */
+    s_orin_tx_q = xQueueCreate(ORIN_TX_QUEUE_DEPTH, sizeof(orin_tx_frame_t));
+    configASSERT(s_orin_tx_q);
+
+    /* Seed heartbeat timer so we don't immediately timeout */
+    g_orin_ctrl.hb_last_ms = (uint32_t)(esp_timer_get_time() / 1000LL);
+
+    /* Create tasks */
+    xTaskCreate(orin_serial_rx_task, "orin_rx",  4096, s_orin_tx_q, 10, NULL);
+    xTaskCreate(orin_serial_tx_task, "orin_tx",  2048, s_orin_tx_q,  9, NULL);
+    xTaskCreate(vesc_can_rx_task,    "vesc_rx",  4096, s_orin_tx_q, 10, NULL);
+    xTaskCreate(telem_task,          "telem",    2048, NULL,          5, NULL);
+    xTaskCreate(drive_task,          "drive",    2048, NULL,          8, NULL);
+
+    /* OTA subsystem — WiFi version checker + display overlay */
+    gitea_ota_init();
+    ota_display_init();
+
+    ESP_LOGI(TAG, "all tasks started");
+    /* app_main returns — FreeRTOS scheduler continues */
+}

esp32s3/balance/main/orin_serial.c

@@ -0,0 +1,334 @@
+/* orin_serial.c — Orin↔ESP32-S3 serial protocol (bd-66hx + bd-1s1s OTA cmds) */
+
+#include "orin_serial.h"
+#include "config.h"
+#include "gitea_ota.h"
+#include "ota_self.h"
+#include "uart_ota.h"
+#include "version.h"
+#include "driver/uart.h"
+#include "esp_log.h"
+#include "esp_timer.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/queue.h"
+#include <string.h>
+#include <stdio.h>
+
+static const char *TAG = "orin";
+
+/* ── Shared state ── */
+orin_drive_t   g_orin_drive = {0};
+orin_control_t g_orin_ctrl  = {.armed = false, .estop = false, .hb_last_ms = 0};
+
+/* ── CRC8-SMBUS (poly=0x07, init=0x00) ── */
+static uint8_t crc8(const uint8_t *data, uint8_t len)
+{
+    uint8_t crc = 0x00u;
+    for (uint8_t i = 0; i < len; i++) {
+        crc ^= data[i];
+        for (uint8_t b = 0; b < 8u; b++) {
+            crc = (crc & 0x80u) ? (uint8_t)((crc << 1u) ^ 0x07u) : (uint8_t)(crc << 1u);
+        }
+    }
+    return crc;
+}
+
+/* ── Frame builder ── */
+static void build_frame(orin_tx_frame_t *f, uint8_t out[/* ORIN_MAX_PAYLOAD + 4 */], uint8_t *out_len)
+{
+    /* [SYNC][LEN][TYPE][PAYLOAD...][CRC] */
+    uint8_t crc_buf[2u + ORIN_MAX_PAYLOAD];
+    crc_buf[0] = f->len;
+    crc_buf[1] = f->type;
+    memcpy(&crc_buf[2], f->payload, f->len);
+    uint8_t crc = crc8(crc_buf, (uint8_t)(2u + f->len));
+
+    out[0] = ORIN_SYNC;
+    out[1] = f->len;
+    out[2] = f->type;
+    memcpy(&out[3], f->payload, f->len);
+    out[3u + f->len] = crc;
+    *out_len = (uint8_t)(4u + f->len);
+}
+
+/* ── Enqueue helpers ── */
+static void enqueue(QueueHandle_t q, uint8_t type, const uint8_t *payload, uint8_t len)
+{
+    orin_tx_frame_t f = {.type = type, .len = len};
+    if (len > 0u && payload) {
+        memcpy(f.payload, payload, len);
+    }
+    if (xQueueSend(q, &f, 0) != pdTRUE) {
+        ESP_LOGW(TAG, "tx queue full, dropped type=0x%02x", type);
+    }
+}
+
+void orin_send_ack(QueueHandle_t q, uint8_t cmd_type)
+{
+    enqueue(q, RESP_ACK, &cmd_type, 1u);
+}
+
+void orin_send_nack(QueueHandle_t q, uint8_t cmd_type, uint8_t err)
+{
+    uint8_t p[2] = {cmd_type, err};
+    enqueue(q, RESP_NACK, p, 2u);
+}
+
+void orin_send_status(QueueHandle_t q,
+                      int16_t pitch_x10, int16_t motor_cmd,
+                      uint16_t vbat_mv, bal_state_t state, uint8_t flags)
+{
+    /* int16 pitch_x10, int16 motor_cmd, uint16 vbat_mv, uint8 state, uint8 flags — BE */
+    uint8_t p[8];
+    p[0] = (uint8_t)((uint16_t)pitch_x10 >> 8u);
+    p[1] = (uint8_t)((uint16_t)pitch_x10);
+    p[2] = (uint8_t)((uint16_t)motor_cmd >> 8u);
+    p[3] = (uint8_t)((uint16_t)motor_cmd);
+    p[4] = (uint8_t)(vbat_mv >> 8u);
+    p[5] = (uint8_t)(vbat_mv);
+    p[6] = (uint8_t)state;
+    p[7] = flags;
+    enqueue(q, TELEM_STATUS, p, 8u);
+}
+
+void orin_send_vesc(QueueHandle_t q, uint8_t telem_type,
+                    int32_t erpm, uint16_t voltage_mv,
+                    int16_t current_ma, uint16_t temp_c_x10)
+{
+    /* int32 erpm, uint16 voltage_mv, int16 current_ma, uint16 temp_c_x10 — BE */
+    uint8_t p[10];
+    uint32_t u = (uint32_t)erpm;
+    p[0] = (uint8_t)(u >> 24u);
+    p[1] = (uint8_t)(u >> 16u);
+    p[2] = (uint8_t)(u >>  8u);
+    p[3] = (uint8_t)(u);
+    p[4] = (uint8_t)(voltage_mv >> 8u);
+    p[5] = (uint8_t)(voltage_mv);
+    p[6] = (uint8_t)((uint16_t)current_ma >> 8u);
+    p[7] = (uint8_t)((uint16_t)current_ma);
+    p[8] = (uint8_t)(temp_c_x10 >> 8u);
+    p[9] = (uint8_t)(temp_c_x10);
+    enqueue(q, telem_type, p, 10u);
+}
+
+/* ── UART init ── */
+void orin_serial_init(void)
+{
+    uart_config_t cfg = {
+        .baud_rate  = ORIN_UART_BAUD,
+        .data_bits  = UART_DATA_8_BITS,
+        .parity     = UART_PARITY_DISABLE,
+        .stop_bits  = UART_STOP_BITS_1,
+        .flow_ctrl  = UART_HW_FLOWCTRL_DISABLE,
+    };
+    ESP_ERROR_CHECK(uart_param_config(ORIN_UART_PORT, &cfg));
+    ESP_ERROR_CHECK(uart_set_pin(ORIN_UART_PORT,
+                                  ORIN_UART_TX_GPIO, ORIN_UART_RX_GPIO,
+                                  UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));
+    ESP_ERROR_CHECK(uart_driver_install(ORIN_UART_PORT, ORIN_UART_RX_BUF, 0,
+                                        0, NULL, 0));
+    ESP_LOGI(TAG, "UART%d init OK: tx=%d rx=%d baud=%d",
+             ORIN_UART_PORT, ORIN_UART_TX_GPIO, ORIN_UART_RX_GPIO, ORIN_UART_BAUD);
+}
+
+/* ── RX parser state machine ── */
+typedef enum {
+    WAIT_SYNC,
+    WAIT_LEN,
+    WAIT_TYPE,
+    WAIT_PAYLOAD,
+    WAIT_CRC,
+} rx_state_t;
+
+static void dispatch_cmd(uint8_t type, const uint8_t *payload, uint8_t len,
+                          QueueHandle_t tx_q)
+{
+    uint32_t now_ms = (uint32_t)(esp_timer_get_time() / 1000LL);
+
+    switch (type) {
+    case CMD_HEARTBEAT:
+        g_orin_ctrl.hb_last_ms = now_ms;
+        orin_send_ack(tx_q, type);
+        break;
+
+    case CMD_DRIVE:
+        if (len < 4u) { orin_send_nack(tx_q, type, ERR_BAD_LEN); break; }
+        if (g_orin_ctrl.estop) { orin_send_nack(tx_q, type, ERR_ESTOP_ACTIVE); break; }
+        if (!g_orin_ctrl.armed) { orin_send_nack(tx_q, type, ERR_DISARMED); break; }
+        g_orin_drive.speed      = (int16_t)(((uint16_t)payload[0] << 8u) | payload[1]);
+        g_orin_drive.steer      = (int16_t)(((uint16_t)payload[2] << 8u) | payload[3]);
+        g_orin_drive.updated_ms = now_ms;
+        g_orin_ctrl.hb_last_ms  = now_ms;  /* drive counts as heartbeat */
+        orin_send_ack(tx_q, type);
+        break;
+
+    case CMD_ESTOP:
+        if (len < 1u) { orin_send_nack(tx_q, type, ERR_BAD_LEN); break; }
+        g_orin_ctrl.estop = (payload[0] != 0u);
+        if (g_orin_ctrl.estop) {
+            g_orin_drive.speed = 0;
+            g_orin_drive.steer = 0;
+        }
+        orin_send_ack(tx_q, type);
+        break;
+
+    case CMD_ARM:
+        if (len < 1u) { orin_send_nack(tx_q, type, ERR_BAD_LEN); break; }
+        if (g_orin_ctrl.estop && payload[0] != 0u) {
+            /* cannot arm while estop is active */
+            orin_send_nack(tx_q, type, ERR_ESTOP_ACTIVE);
+            break;
+        }
+        g_orin_ctrl.armed = (payload[0] != 0u);
+        if (!g_orin_ctrl.armed) {
+            g_orin_drive.speed = 0;
+            g_orin_drive.steer = 0;
+        }
+        orin_send_ack(tx_q, type);
+        break;
+
+    case CMD_OTA_CHECK:
+        /* Trigger an immediate Gitea version check */
+        gitea_ota_check_now();
+        orin_send_version_info(tx_q, OTA_TARGET_BALANCE,
+                                BALANCE_FW_VERSION,
+                                g_balance_update.available
+                                    ? g_balance_update.version : "");
+        orin_send_version_info(tx_q, OTA_TARGET_IO,
+                                IO_FW_VERSION,
+                                g_io_update.available
+                                    ? g_io_update.version : "");
+        orin_send_ack(tx_q, type);
+        break;
+
+    case CMD_OTA_UPDATE:
+        if (len < 1u) { orin_send_nack(tx_q, type, ERR_BAD_LEN); break; }
+        {
+            uint8_t target = payload[0];
+            bool triggered = false;
+            if (target == OTA_TARGET_IO || target == OTA_TARGET_BOTH) {
+                if (!uart_ota_trigger()) {
+                    orin_send_nack(tx_q, type,
+                        g_io_update.available ? ERR_OTA_BUSY : ERR_OTA_NO_UPDATE);
+                    break;
+                }
+                triggered = true;
+            }
+            if (target == OTA_TARGET_BALANCE || target == OTA_TARGET_BOTH) {
+                if (!ota_self_trigger()) {
+                    if (!triggered) {
+                        orin_send_nack(tx_q, type,
+                            g_balance_update.available ? ERR_OTA_BUSY : ERR_OTA_NO_UPDATE);
+                        break;
+                    }
+                }
+            }
+            orin_send_ack(tx_q, type);
+        }
+        break;
+
+    default:
+        ESP_LOGW(TAG, "unknown cmd type=0x%02x", type);
+        break;
+    }
+}
+
+void orin_serial_rx_task(void *arg)
+{
+    QueueHandle_t tx_q = (QueueHandle_t)arg;
+    rx_state_t state   = WAIT_SYNC;
+    uint8_t    rx_len  = 0;
+    uint8_t    rx_type = 0;
+    uint8_t    payload[ORIN_MAX_PAYLOAD];
+    uint8_t    pay_idx = 0;
+
+    uint8_t byte;
+    for (;;) {
+        int r = uart_read_bytes(ORIN_UART_PORT, &byte, 1, pdMS_TO_TICKS(10));
+        if (r <= 0) {
+            continue;
+        }
+
+        switch (state) {
+        case WAIT_SYNC:
+            if (byte == ORIN_SYNC) { state = WAIT_LEN; }
+            break;
+
+        case WAIT_LEN:
+            if (byte > ORIN_MAX_PAYLOAD) {
+                /* oversize — send NACK and reset */
+                orin_send_nack(tx_q, 0x00u, ERR_BAD_LEN);
+                state = WAIT_SYNC;
+            } else {
+                rx_len = byte;
+                state  = WAIT_TYPE;
+            }
+            break;
+
+        case WAIT_TYPE:
+            rx_type = byte;
+            pay_idx = 0u;
+            state   = (rx_len == 0u) ? WAIT_CRC : WAIT_PAYLOAD;
+            break;
+
+        case WAIT_PAYLOAD:
+            payload[pay_idx++] = byte;
+            if (pay_idx == rx_len) { state = WAIT_CRC; }
+            break;
+
+        case WAIT_CRC: {
+            /* Verify CRC over [LEN, TYPE, PAYLOAD] */
+            uint8_t crc_buf[2u + ORIN_MAX_PAYLOAD];
+            crc_buf[0] = rx_len;
+            crc_buf[1] = rx_type;
+            memcpy(&crc_buf[2], payload, rx_len);
+            uint8_t expected = crc8(crc_buf, (uint8_t)(2u + rx_len));
+            if (byte != expected) {
+                ESP_LOGW(TAG, "CRC fail type=0x%02x got=0x%02x exp=0x%02x",
+                         rx_type, byte, expected);
+                orin_send_nack(tx_q, rx_type, ERR_BAD_CRC);
+            } else {
+                dispatch_cmd(rx_type, payload, rx_len, tx_q);
+            }
+            state = WAIT_SYNC;
+            break;
+        }
+        }
+    }
+}
+
+void orin_serial_tx_task(void *arg)
+{
+    QueueHandle_t tx_q = (QueueHandle_t)arg;
+    orin_tx_frame_t f;
+    uint8_t wire[4u + ORIN_MAX_PAYLOAD];
+    uint8_t wire_len;
+
+    for (;;) {
+        if (xQueueReceive(tx_q, &f, portMAX_DELAY) == pdTRUE) {
+            build_frame(&f, wire, &wire_len);
+            uart_write_bytes(ORIN_UART_PORT, (const char *)wire, wire_len);
+        }
+    }
+}
+
+/* ── OTA telemetry helpers (bd-1s1s) ── */
+
+void orin_send_ota_status(QueueHandle_t q, uint8_t target,
+                           uint8_t state, uint8_t progress, uint8_t err)
+{
+    /* TELEM_OTA_STATUS: uint8 target, uint8 state, uint8 progress, uint8 err */
+    uint8_t p[4] = {target, state, progress, err};
+    enqueue(q, TELEM_OTA_STATUS, p, 4u);
+}
+
+void orin_send_version_info(QueueHandle_t q, uint8_t target,
+                             const char *current, const char *available)
+{
+    /* TELEM_VERSION_INFO: uint8 target, char current[16], char available[16] */
+    uint8_t p[33];
+    p[0] = target;
+    strncpy((char *)&p[1],  current,   16); p[16] = '\0';
+    strncpy((char *)&p[17], available ? available : "", 16); p[32] = '\0';
+    enqueue(q, TELEM_VERSION_INFO, p, 33u);
+}

esp32s3/balance/main/orin_serial.h

@@ -0,0 +1,105 @@
+#pragma once
+/* orin_serial.h — Orin↔ESP32-S3 BALANCE USB/UART serial protocol (bd-66hx)
+ *
+ * Frame layout (matches bd-wim1 esp32_balance_protocol.py exactly):
+ *   [0xAA][LEN][TYPE][PAYLOAD × LEN bytes][CRC8-SMBUS]
+ *   CRC covers LEN + TYPE + PAYLOAD bytes.
+ *   All multi-byte payload fields are big-endian.
+ *
+ * Physical: UART0 → CH343 USB-serial → Orin /dev/esp32-balance  @ 460800 baud
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/queue.h"
+
+/* ── Frame constants ── */
+#define ORIN_SYNC           0xAAu
+#define ORIN_MAX_PAYLOAD    62u
+
+/* ── Command types: Orin → ESP32 ── */
+#define CMD_HEARTBEAT       0x01u
+#define CMD_DRIVE           0x02u   /* int16 speed + int16 steer, BE */
+#define CMD_ESTOP           0x03u   /* uint8: 1=assert, 0=clear */
+#define CMD_ARM             0x04u   /* uint8: 1=arm, 0=disarm */
+
+/* ── Telemetry types: ESP32 → Orin ── */
+#define TELEM_STATUS        0x80u   /* status @ 10 Hz */
+#define TELEM_VESC_LEFT     0x81u   /* VESC ID 61 (front) telemetry @ 10 Hz */
+#define TELEM_VESC_RIGHT    0x82u   /* VESC ID 79 (rear)  telemetry @ 10 Hz */
+#define TELEM_OTA_STATUS    0x83u   /* OTA state + progress (bd-1s1s) */
+#define TELEM_VERSION_INFO  0x84u   /* firmware version report (bd-1s1s) */
+#define RESP_ACK            0xA0u
+#define RESP_NACK           0xA1u
+
+/* ── OTA commands (Orin → ESP32, bd-1s1s) ── */
+#define CMD_OTA_CHECK       0x10u   /* no payload: trigger Gitea version check */
+#define CMD_OTA_UPDATE      0x11u   /* uint8 target: 0=balance, 1=io, 2=both */
+
+/* ── OTA target constants ── */
+#define OTA_TARGET_BALANCE  0x00u
+#define OTA_TARGET_IO       0x01u
+#define OTA_TARGET_BOTH     0x02u
+
+/* ── NACK error codes ── */
+#define ERR_BAD_CRC         0x01u
+#define ERR_BAD_LEN         0x02u
+#define ERR_ESTOP_ACTIVE    0x03u
+#define ERR_DISARMED        0x04u
+#define ERR_OTA_BUSY        0x05u
+#define ERR_OTA_NO_UPDATE   0x06u
+
+/* ── Drive state (mirrored from TELEM_STATUS.balance_state) ── */
+typedef enum {
+    BAL_DISARMED = 0,
+    BAL_ARMED    = 1,
+    BAL_ESTOP    = 3,
+} bal_state_t;
+
+/* ── Shared state written by RX task, consumed by main/vesc tasks ── */
+typedef struct {
+    volatile int16_t  speed;        /* -1000..+1000 */
+    volatile int16_t  steer;        /* -1000..+1000 */
+    volatile uint32_t updated_ms;   /* esp_timer tick at last CMD_DRIVE */
+} orin_drive_t;
+
+typedef struct {
+    volatile bool     armed;
+    volatile bool     estop;
+    volatile uint32_t hb_last_ms;   /* esp_timer tick at last CMD_HEARTBEAT/CMD_DRIVE */
+} orin_control_t;
+
+/* ── TX frame queue item ── */
+typedef struct {
+    uint8_t type;
+    uint8_t len;
+    uint8_t payload[ORIN_MAX_PAYLOAD];
+} orin_tx_frame_t;
+
+/* ── Globals (defined in orin_serial.c, extern here) ── */
+extern orin_drive_t   g_orin_drive;
+extern orin_control_t g_orin_ctrl;
+
+/* ── API ── */
+void orin_serial_init(void);
+
+/* Tasks — pass tx_queue as arg to both */
+void orin_serial_rx_task(void *arg);   /* arg = QueueHandle_t tx_queue */
+void orin_serial_tx_task(void *arg);   /* arg = QueueHandle_t tx_queue */
+
+/* Enqueue outbound frames */
+void orin_send_status(QueueHandle_t q,
+                      int16_t pitch_x10, int16_t motor_cmd,
+                      uint16_t vbat_mv, bal_state_t state, uint8_t flags);
+void orin_send_vesc(QueueHandle_t q, uint8_t telem_type,
+                    int32_t erpm, uint16_t voltage_mv,
+                    int16_t current_ma, uint16_t temp_c_x10);
+void orin_send_ack(QueueHandle_t q, uint8_t cmd_type);
+void orin_send_nack(QueueHandle_t q, uint8_t cmd_type, uint8_t err);
+
+/* OTA telemetry helpers (bd-1s1s) */
+void orin_send_ota_status(QueueHandle_t q, uint8_t target,
+                           uint8_t state, uint8_t progress, uint8_t err);
+void orin_send_version_info(QueueHandle_t q, uint8_t target,
+                             const char *current, const char *available);

esp32s3/balance/main/ota_display.c

@@ -0,0 +1,150 @@
+/* ota_display.c — OTA notification/progress UI on GC9A01 (bd-1yr8)
+ *
+ * Renders OTA state overlaid on the 240×240 round HUD display:
+ *   - BADGE: small dot on top-right when update available (idle state)
+ *   - UPDATE SCREEN: version compare, Update Balance / Update IO / Update All
+ *   - PROGRESS: arc around display perimeter + % + status text
+ *   - ERROR: red banner + "RETRY" prompt
+ *
+ * The display_draw_* primitives must be provided by the GC9A01 driver.
+ * Actual SPI driver implementation is in a separate driver bead.
+ */
+
+#include "ota_display.h"
+#include "gitea_ota.h"
+#include "version.h"
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include <stdio.h>
+#include <string.h>
+
+static const char *TAG = "ota_disp";
+
+/* Display centre and radius for the 240×240 GC9A01 */
+#define CX   120
+#define CY   120
+#define RAD  110
+
+/* ── Availability badge: 8×8 dot at top-right of display ── */
+static void draw_badge(bool balance_avail, bool io_avail)
+{
+    uint16_t col = (balance_avail || io_avail) ? COL_ORANGE : COL_BG;
+    display_fill_rect(200, 15, 12, 12, col);
+}
+
+/* ── Progress arc: sweeps 0→360° proportional to progress% ── */
+static void draw_progress_arc(uint8_t pct, uint16_t color)
+{
+    int end_deg = (int)(360 * pct / 100);
+    display_draw_arc(CX, CY, RAD, 0, end_deg, 6, color);
+}
+
+/* ── Status banner: 2 lines of text centred on display ── */
+static void draw_status(const char *line1, const char *line2,
+                         uint16_t fg, uint16_t bg)
+{
+    display_fill_rect(20, 90, 200, 60, bg);
+    if (line1 && line1[0])
+        display_draw_string(CX - (int)(strlen(line1) * 6 / 2), 96,
+                             line1, fg, bg);
+    if (line2 && line2[0])
+        display_draw_string(CX - (int)(strlen(line2) * 6 / 2), 116,
+                             line2, fg, bg);
+}
+
+/* ── Main render logic ── */
+void ota_display_update(void)
+{
+    /* Determine dominant OTA state */
+    ota_self_state_t  self  = g_ota_self_state;
+    uart_ota_send_state_t io_s = g_uart_ota_state;
+
+    switch (self) {
+    case OTA_SELF_DOWNLOADING:
+    case OTA_SELF_VERIFYING:
+    case OTA_SELF_APPLYING: {
+        /* Balance self-update in progress */
+        char pct_str[16];
+        snprintf(pct_str, sizeof(pct_str), "%d%%", g_ota_self_progress);
+        const char *phase = (self == OTA_SELF_VERIFYING) ? "Verifying..." :
+                            (self == OTA_SELF_APPLYING)  ? "Applying..." :
+                                                            "Downloading...";
+        draw_progress_arc(g_ota_self_progress, COL_BLUE);
+        draw_status("Updating Balance", pct_str, COL_WHITE, COL_BG);
+        ESP_LOGD(TAG, "balance OTA %s %d%%", phase, g_ota_self_progress);
+        return;
+    }
+    case OTA_SELF_REBOOTING:
+        draw_status("Update complete", "Rebooting...", COL_GREEN, COL_BG);
+        return;
+    case OTA_SELF_FAILED:
+        draw_progress_arc(0, COL_RED);
+        draw_status("Balance update", "FAILED  RETRY?", COL_RED, COL_BG);
+        return;
+    default:
+        break;
+    }
+
+    switch (io_s) {
+    case UART_OTA_S_DOWNLOADING:
+        draw_progress_arc(g_uart_ota_progress, COL_YELLOW);
+        draw_status("Downloading IO", "firmware...", COL_WHITE, COL_BG);
+        return;
+    case UART_OTA_S_SENDING: {
+        char pct_str[16];
+        snprintf(pct_str, sizeof(pct_str), "%d%%", g_uart_ota_progress);
+        draw_progress_arc(g_uart_ota_progress, COL_YELLOW);
+        draw_status("Updating IO", pct_str, COL_WHITE, COL_BG);
+        return;
+    }
+    case UART_OTA_S_DONE:
+        draw_status("IO update done", "", COL_GREEN, COL_BG);
+        return;
+    case UART_OTA_S_FAILED:
+        draw_progress_arc(0, COL_RED);
+        draw_status("IO update", "FAILED  RETRY?", COL_RED, COL_BG);
+        return;
+    default:
+        break;
+    }
+
+    /* Idle — show badge if update available */
+    bool bal_avail = g_balance_update.available;
+    bool io_avail  = g_io_update.available;
+    draw_badge(bal_avail, io_avail);
+
+    if (bal_avail || io_avail) {
+        /* Show available versions on display when idle */
+        char verline[48];
+        if (bal_avail) {
+            snprintf(verline, sizeof(verline), "Bal v%s rdy",
+                     g_balance_update.version);
+            draw_status(verline, io_avail ? "IO update rdy" : "",
+                         COL_ORANGE, COL_BG);
+        } else if (io_avail) {
+            snprintf(verline, sizeof(verline), "IO v%s rdy",
+                     g_io_update.version);
+            draw_status(verline, "", COL_ORANGE, COL_BG);
+        }
+    } else {
+        /* Clear OTA overlay area */
+        display_fill_rect(20, 90, 200, 60, COL_BG);
+        draw_badge(false, false);
+    }
+}
+
+/* ── Background display task (5 Hz) ── */
+static void ota_display_task(void *arg)
+{
+    for (;;) {
+        vTaskDelay(pdMS_TO_TICKS(200));
+        ota_display_update();
+    }
+}
+
+void ota_display_init(void)
+{
+    xTaskCreate(ota_display_task, "ota_disp", 2048, NULL, 3, NULL);
+    ESP_LOGI(TAG, "OTA display task started");
+}

esp32s3/balance/main/ota_display.h

@@ -0,0 +1,33 @@
+#pragma once
+/* ota_display.h — OTA notification UI on GC9A01 round LCD (bd-1yr8)
+ *
+ * GC9A01 240×240 round display via SPI (IO12 CS, IO11 DC, IO10 RST, IO9 BL).
+ * Calls into display_draw_* primitives (provided by display driver layer).
+ * This module owns the "OTA notification overlay" rendered over the HUD.
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "ota_self.h"
+#include "uart_ota.h"
+
+/* ── Display primitives API (must be provided by display driver) ── */
+void display_fill_rect(int x, int y, int w, int h, uint16_t rgb565);
+void display_draw_string(int x, int y, const char *str, uint16_t fg, uint16_t bg);
+void display_draw_arc(int cx, int cy, int r, int start_deg, int end_deg,
+                       int thickness, uint16_t color);
+
+/* ── Colour palette (RGB565) ── */
+#define COL_BG       0x0000u  /* black */
+#define COL_WHITE    0xFFFFu
+#define COL_GREEN    0x07E0u
+#define COL_YELLOW   0xFFE0u
+#define COL_RED      0xF800u
+#define COL_BLUE     0x001Fu
+#define COL_ORANGE   0xFD20u
+
+/* ── OTA display task: runs at 5 Hz, overlays OTA state on HUD ── */
+void ota_display_init(void);
+
+/* Called from main loop or display task to render the OTA overlay */
+void ota_display_update(void);

esp32s3/balance/main/ota_self.c

@@ -0,0 +1,183 @@
+/* ota_self.c — Balance self-OTA (bd-18nb)
+ *
+ * Uses esp_https_ota / esp_ota_ops to download from Gitea release URL,
+ * stream-verify SHA256 with mbedTLS, set new boot partition, and reboot.
+ * CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE in sdkconfig allows auto-rollback
+ * if the new image doesn't call esp_ota_mark_app_valid_cancel_rollback()
+ * within OTA_ROLLBACK_WINDOW_S seconds.
+ */
+
+#include "ota_self.h"
+#include "gitea_ota.h"
+#include "esp_log.h"
+#include "esp_ota_ops.h"
+#include "esp_http_client.h"
+#include "esp_timer.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "mbedtls/sha256.h"
+#include <string.h>
+#include <stdio.h>
+
+static const char *TAG = "ota_self";
+
+volatile ota_self_state_t g_ota_self_state   = OTA_SELF_IDLE;
+volatile uint8_t          g_ota_self_progress = 0;
+
+#define OTA_CHUNK_SIZE  4096
+
+/* ── SHA256 verify helper ── */
+static bool sha256_matches(const uint8_t *digest, const char *expected_hex)
+{
+    if (!expected_hex || expected_hex[0] == '\0') {
+        ESP_LOGW(TAG, "no SHA256 to verify — skipping");
+        return true;
+    }
+    char got[65] = {0};
+    for (int i = 0; i < 32; i++) {
+        snprintf(&got[i*2], 3, "%02x", digest[i]);
+    }
+    bool ok = (strncasecmp(got, expected_hex, 64) == 0);
+    if (!ok) {
+        ESP_LOGE(TAG, "SHA256 mismatch: got=%s exp=%s", got, expected_hex);
+    }
+    return ok;
+}
+
+/* ── OTA download + flash task ── */
+static void ota_self_task(void *arg)
+{
+    const char *url    = g_balance_update.download_url;
+    const char *sha256 = g_balance_update.sha256;
+
+    g_ota_self_state    = OTA_SELF_DOWNLOADING;
+    g_ota_self_progress = 0;
+
+    ESP_LOGI(TAG, "OTA start: %s", url);
+
+    esp_ota_handle_t       handle     = 0;
+    const esp_partition_t *ota_part   = esp_ota_get_next_update_partition(NULL);
+    if (!ota_part) {
+        ESP_LOGE(TAG, "no OTA partition");
+        g_ota_self_state = OTA_SELF_FAILED;
+        vTaskDelete(NULL);
+        return;
+    }
+
+    esp_err_t err = esp_ota_begin(ota_part, OTA_WITH_SEQUENTIAL_WRITES, &handle);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "ota_begin: %s", esp_err_to_name(err));
+        g_ota_self_state = OTA_SELF_FAILED;
+        vTaskDelete(NULL);
+        return;
+    }
+
+    /* Setup HTTP client */
+    esp_http_client_config_t hcfg = {
+        .url        = url,
+        .timeout_ms = 30000,
+        .buffer_size = OTA_CHUNK_SIZE,
+        .skip_cert_common_name_check = true,
+    };
+    esp_http_client_handle_t client = esp_http_client_init(&hcfg);
+    err = esp_http_client_open(client, 0);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "http_open: %s", esp_err_to_name(err));
+        esp_ota_abort(handle);
+        esp_http_client_cleanup(client);
+        g_ota_self_state = OTA_SELF_FAILED;
+        vTaskDelete(NULL);
+        return;
+    }
+
+    int content_len = esp_http_client_fetch_headers(client);
+    ESP_LOGI(TAG, "content-length: %d", content_len);
+
+    mbedtls_sha256_context sha_ctx;
+    mbedtls_sha256_init(&sha_ctx);
+    mbedtls_sha256_starts(&sha_ctx, 0);  /* 0 = SHA-256 */
+
+    static uint8_t buf[OTA_CHUNK_SIZE];
+    int total = 0;
+    int rd;
+    while ((rd = esp_http_client_read(client, (char *)buf, sizeof(buf))) > 0) {
+        mbedtls_sha256_update(&sha_ctx, buf, rd);
+        err = esp_ota_write(handle, buf, rd);
+        if (err != ESP_OK) {
+            ESP_LOGE(TAG, "ota_write: %s", esp_err_to_name(err));
+            esp_ota_abort(handle);
+            goto cleanup;
+        }
+        total += rd;
+        if (content_len > 0) {
+            g_ota_self_progress = (uint8_t)((total * 100) / content_len);
+        }
+    }
+    esp_http_client_close(client);
+
+    /* Verify SHA256 */
+    g_ota_self_state = OTA_SELF_VERIFYING;
+    uint8_t digest[32];
+    mbedtls_sha256_finish(&sha_ctx, digest);
+    if (!sha256_matches(digest, sha256)) {
+        ESP_LOGE(TAG, "SHA256 verification failed");
+        esp_ota_abort(handle);
+        g_ota_self_state = OTA_SELF_FAILED;
+        goto cleanup;
+    }
+
+    /* Finalize + set boot partition */
+    g_ota_self_state = OTA_SELF_APPLYING;
+    err = esp_ota_end(handle);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "ota_end: %s", esp_err_to_name(err));
+        g_ota_self_state = OTA_SELF_FAILED;
+        goto cleanup;
+    }
+
+    err = esp_ota_set_boot_partition(ota_part);
+    if (err != ESP_OK) {
+        ESP_LOGE(TAG, "set_boot_partition: %s", esp_err_to_name(err));
+        g_ota_self_state = OTA_SELF_FAILED;
+        goto cleanup;
+    }
+
+    g_ota_self_state    = OTA_SELF_REBOOTING;
+    g_ota_self_progress = 100;
+    ESP_LOGI(TAG, "OTA success — rebooting");
+    vTaskDelay(pdMS_TO_TICKS(500));
+    esp_restart();
+
+cleanup:
+    mbedtls_sha256_free(&sha_ctx);
+    esp_http_client_cleanup(client);
+    handle = 0;
+    vTaskDelete(NULL);
+}
+
+bool ota_self_trigger(void)
+{
+    if (!g_balance_update.available) {
+        ESP_LOGW(TAG, "no update available");
+        return false;
+    }
+    if (g_ota_self_state != OTA_SELF_IDLE) {
+        ESP_LOGW(TAG, "OTA already in progress (state=%d)", g_ota_self_state);
+        return false;
+    }
+    xTaskCreate(ota_self_task, "ota_self", 8192, NULL, 5, NULL);
+    return true;
+}
+
+void ota_self_health_check(void)
+{
+    /* Mark running image as valid — prevents rollback */
+    esp_err_t err = esp_ota_mark_app_valid_cancel_rollback();
+    if (err == ESP_OK) {
+        ESP_LOGI(TAG, "image marked valid");
+    } else if (err == ESP_ERR_NOT_SUPPORTED) {
+        /* Not an OTA image (e.g., flashed via JTAG) — ignore */
+    } else {
+        ESP_LOGW(TAG, "mark_valid: %s", esp_err_to_name(err));
+    }
+}

esp32s3/balance/main/ota_self.h

@@ -0,0 +1,34 @@
+#pragma once
+/* ota_self.h — Balance self-OTA (bd-18nb)
+ *
+ * Downloads balance-firmware.bin from Gitea release URL to the inactive
+ * OTA partition, verifies SHA256, sets boot partition, reboots.
+ * Auto-rollback if health check not called within ROLLBACK_WINDOW_S seconds.
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#define OTA_ROLLBACK_WINDOW_S  30
+
+typedef enum {
+    OTA_SELF_IDLE      = 0,
+    OTA_SELF_CHECKING,    /* (unused — gitea_ota handles this) */
+    OTA_SELF_DOWNLOADING,
+    OTA_SELF_VERIFYING,
+    OTA_SELF_APPLYING,
+    OTA_SELF_REBOOTING,
+    OTA_SELF_FAILED,
+} ota_self_state_t;
+
+extern volatile ota_self_state_t g_ota_self_state;
+extern volatile uint8_t          g_ota_self_progress; /* 0-100 % */
+
+/* Trigger a Balance self-update.
+ * Uses g_balance_update (from gitea_ota). Non-blocking: starts in a task.
+ * Returns false if no update available or OTA already in progress. */
+bool ota_self_trigger(void);
+
+/* Called from app_main after boot to mark the running image as valid.
+ * Must be called within OTA_ROLLBACK_WINDOW_S after boot or rollback fires. */
+void ota_self_health_check(void);

esp32s3/balance/main/uart_ota.c

@@ -0,0 +1,241 @@
+/* uart_ota.c — UART OTA sender: Balance→IO board (bd-21hv)
+ *
+ * Downloads io-firmware.bin from Gitea, then sends to IO board via UART1.
+ * IO board must update itself BEFORE Balance self-update (per spec).
+ */
+
+#include "uart_ota.h"
+#include "gitea_ota.h"
+#include "esp_log.h"
+#include "esp_http_client.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "mbedtls/sha256.h"
+#include <string.h>
+#include <stdio.h>
+
+static const char *TAG = "uart_ota";
+
+volatile uart_ota_send_state_t g_uart_ota_state    = UART_OTA_S_IDLE;
+volatile uint8_t               g_uart_ota_progress  = 0;
+
+/* ── CRC8-SMBUS ── */
+static uint8_t crc8(const uint8_t *d, uint16_t len)
+{
+    uint8_t crc = 0;
+    for (uint16_t i = 0; i < len; i++) {
+        crc ^= d[i];
+        for (uint8_t b = 0; b < 8; b++)
+            crc = (crc & 0x80u) ? (uint8_t)((crc << 1u) ^ 0x07u) : (uint8_t)(crc << 1u);
+    }
+    return crc;
+}
+
+/* ── Build and send one UART OTA frame ── */
+static void send_frame(uint8_t type, uint16_t seq,
+                        const uint8_t *payload, uint16_t plen)
+{
+    /* [TYPE:1][SEQ:2 BE][LEN:2 BE][PAYLOAD][CRC8:1] */
+    uint8_t hdr[5];
+    hdr[0] = type;
+    hdr[1] = (uint8_t)(seq >> 8u);
+    hdr[2] = (uint8_t)(seq);
+    hdr[3] = (uint8_t)(plen >> 8u);
+    hdr[4] = (uint8_t)(plen);
+
+    /* CRC over hdr + payload */
+    uint8_t crc_buf[5 + OTA_UART_CHUNK_SIZE];
+    memcpy(crc_buf, hdr, 5);
+    if (plen > 0 && payload) memcpy(crc_buf + 5, payload, plen);
+    uint8_t crc = crc8(crc_buf, (uint16_t)(5 + plen));
+
+    uart_write_bytes(UART_OTA_PORT, (char *)hdr, 5);
+    if (plen > 0 && payload)
+        uart_write_bytes(UART_OTA_PORT, (char *)payload, plen);
+    uart_write_bytes(UART_OTA_PORT, (char *)&crc, 1);
+}
+
+/* ── Wait for ACK/NACK from IO board ── */
+static bool wait_ack(uint16_t expected_seq)
+{
+    /* Response frame: [TYPE:1][SEQ:2][LEN:2][PAYLOAD][CRC:1] */
+    uint8_t buf[16];
+    int timeout = OTA_UART_ACK_TIMEOUT_MS;
+    int got = 0;
+
+    while (timeout > 0 && got < 6) {
+        int r = uart_read_bytes(UART_OTA_PORT, buf + got, 1, pdMS_TO_TICKS(50));
+        if (r > 0) got++;
+        else timeout -= 50;
+    }
+
+    if (got < 3) return false;
+
+    uint8_t type = buf[0];
+    uint16_t seq = (uint16_t)((buf[1] << 8u) | buf[2]);
+
+    if (type == UART_OTA_ACK && seq == expected_seq) return true;
+    if (type == UART_OTA_NACK) {
+        uint8_t err = (got >= 6) ? buf[5] : 0;
+        ESP_LOGW(TAG, "NACK seq=%u err=%u", seq, err);
+    }
+    return false;
+}
+
+/* ── Download firmware to RAM buffer (max 1.75 MB) ── */
+static uint8_t *download_io_firmware(uint32_t *out_size)
+{
+    const char *url = g_io_update.download_url;
+    ESP_LOGI(TAG, "downloading IO fw: %s", url);
+
+    esp_http_client_config_t cfg = {
+        .url = url, .timeout_ms = 30000,
+        .skip_cert_common_name_check = true,
+    };
+    esp_http_client_handle_t client = esp_http_client_init(&cfg);
+    if (esp_http_client_open(client, 0) != ESP_OK) {
+        esp_http_client_cleanup(client);
+        return NULL;
+    }
+
+    int content_len = esp_http_client_fetch_headers(client);
+    if (content_len <= 0 || content_len > (int)(0x1B0000)) {
+        ESP_LOGE(TAG, "bad content-length: %d", content_len);
+        esp_http_client_cleanup(client);
+        return NULL;
+    }
+
+    uint8_t *buf = malloc(content_len);
+    if (!buf) {
+        ESP_LOGE(TAG, "malloc %d failed", content_len);
+        esp_http_client_cleanup(client);
+        return NULL;
+    }
+
+    int total = 0, rd;
+    while ((rd = esp_http_client_read(client, (char *)buf + total,
+                                       content_len - total)) > 0) {
+        total += rd;
+        g_uart_ota_progress = (uint8_t)((total * 50) / content_len); /* 0-50% for download */
+    }
+    esp_http_client_cleanup(client);
+
+    if (total != content_len) {
+        free(buf);
+        return NULL;
+    }
+    *out_size = (uint32_t)total;
+    return buf;
+}
+
+/* ── UART OTA send task ── */
+static void uart_ota_task(void *arg)
+{
+    g_uart_ota_state    = UART_OTA_S_DOWNLOADING;
+    g_uart_ota_progress = 0;
+
+    uint32_t fw_size = 0;
+    uint8_t *fw = download_io_firmware(&fw_size);
+    if (!fw) {
+        ESP_LOGE(TAG, "download failed");
+        g_uart_ota_state = UART_OTA_S_FAILED;
+        vTaskDelete(NULL);
+        return;
+    }
+
+    /* Compute SHA256 of downloaded firmware */
+    uint8_t digest[32];
+    mbedtls_sha256_context sha;
+    mbedtls_sha256_init(&sha);
+    mbedtls_sha256_starts(&sha, 0);
+    mbedtls_sha256_update(&sha, fw, fw_size);
+    mbedtls_sha256_finish(&sha, digest);
+    mbedtls_sha256_free(&sha);
+
+    g_uart_ota_state = UART_OTA_S_SENDING;
+
+    /* Send OTA_BEGIN: uint32 size + uint8[32] sha256 */
+    uint8_t begin_payload[36];
+    begin_payload[0] = (uint8_t)(fw_size >> 24u);
+    begin_payload[1] = (uint8_t)(fw_size >> 16u);
+    begin_payload[2] = (uint8_t)(fw_size >>  8u);
+    begin_payload[3] = (uint8_t)(fw_size);
+    memcpy(&begin_payload[4], digest, 32);
+
+    for (int retry = 0; retry < OTA_UART_MAX_RETRIES; retry++) {
+        send_frame(UART_OTA_BEGIN, 0, begin_payload, 36);
+        if (wait_ack(0)) goto send_data;
+        ESP_LOGW(TAG, "BEGIN retry %d", retry);
+    }
+    ESP_LOGE(TAG, "BEGIN failed");
+    free(fw);
+    g_uart_ota_state = UART_OTA_S_FAILED;
+    vTaskDelete(NULL);
+    return;
+
+send_data: {
+    uint32_t offset = 0;
+    uint16_t seq    = 1;
+    while (offset < fw_size) {
+        uint16_t chunk = (uint16_t)((fw_size - offset) < OTA_UART_CHUNK_SIZE
+                          ? (fw_size - offset) : OTA_UART_CHUNK_SIZE);
+        bool acked = false;
+        for (int retry = 0; retry < OTA_UART_MAX_RETRIES; retry++) {
+            send_frame(UART_OTA_DATA, seq, fw + offset, chunk);
+            if (wait_ack(seq)) { acked = true; break; }
+            ESP_LOGW(TAG, "DATA seq=%u retry=%d", seq, retry);
+        }
+        if (!acked) {
+            ESP_LOGE(TAG, "DATA seq=%u failed", seq);
+            send_frame(UART_OTA_ABORT, seq, NULL, 0);
+            free(fw);
+            g_uart_ota_state = UART_OTA_S_FAILED;
+            vTaskDelete(NULL);
+            return;
+        }
+        offset += chunk;
+        seq++;
+        /* 50-100% for sending phase */
+        g_uart_ota_progress = (uint8_t)(50u + (offset * 50u) / fw_size);
+    }
+
+    /* Send OTA_END */
+    for (int retry = 0; retry < OTA_UART_MAX_RETRIES; retry++) {
+        send_frame(UART_OTA_END, seq, NULL, 0);
+        if (wait_ack(seq)) break;
+    }
+    }
+
+    free(fw);
+    g_uart_ota_progress = 100;
+    g_uart_ota_state    = UART_OTA_S_DONE;
+    ESP_LOGI(TAG, "IO OTA complete — %lu bytes sent", (unsigned long)fw_size);
+    vTaskDelete(NULL);
+}
+
+bool uart_ota_trigger(void)
+{
+    if (!g_io_update.available) {
+        ESP_LOGW(TAG, "no IO update available");
+        return false;
+    }
+    if (g_uart_ota_state != UART_OTA_S_IDLE) {
+        ESP_LOGW(TAG, "UART OTA busy (state=%d)", g_uart_ota_state);
+        return false;
+    }
+    /* Init UART1 for OTA */
+    uart_config_t ucfg = {
+        .baud_rate  = UART_OTA_BAUD,
+        .data_bits  = UART_DATA_8_BITS,
+        .parity     = UART_PARITY_DISABLE,
+        .stop_bits  = UART_STOP_BITS_1,
+        .flow_ctrl  = UART_HW_FLOWCTRL_DISABLE,
+    };
+    uart_param_config(UART_OTA_PORT, &ucfg);
+    uart_set_pin(UART_OTA_PORT, UART_OTA_TX_GPIO, UART_OTA_RX_GPIO,
+                  UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE);
+    uart_driver_install(UART_OTA_PORT, 2048, 0, 0, NULL, 0);
+
+    xTaskCreate(uart_ota_task, "uart_ota", 16384, NULL, 4, NULL);
+    return true;
+}

esp32s3/balance/main/uart_ota.h

@@ -0,0 +1,64 @@
+#pragma once
+/* uart_ota.h — UART OTA protocol for Balance→IO firmware update (bd-21hv)
+ *
+ * Balance downloads io-firmware.bin from Gitea, then streams it to the IO
+ * board over UART1 (GPIO17/18, 460800 baud) in 1 KB chunks with ACK.
+ *
+ * Protocol frame format (both directions):
+ *   [TYPE:1][SEQ:2 BE][LEN:2 BE][PAYLOAD:LEN][CRC8:1]
+ *   CRC8-SMBUS over TYPE+SEQ+LEN+PAYLOAD.
+ *
+ * Balance→IO:
+ *   OTA_BEGIN  (0xC0) payload: uint32 total_size BE + uint8[32] sha256
+ *   OTA_DATA   (0xC1) payload: uint8[] chunk (up to 1024 bytes)
+ *   OTA_END    (0xC2) no payload
+ *   OTA_ABORT  (0xC3) no payload
+ *
+ * IO→Balance:
+ *   OTA_ACK    (0xC4) payload: uint16 acked_seq BE
+ *   OTA_NACK   (0xC5) payload: uint16 failed_seq BE + uint8 err_code
+ *   OTA_STATUS (0xC6) payload: uint8 state + uint8 progress%
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/* UART for Balance→IO OTA */
+#include "driver/uart.h"
+#define UART_OTA_PORT       UART_NUM_1
+#define UART_OTA_BAUD       460800
+#define UART_OTA_TX_GPIO    17
+#define UART_OTA_RX_GPIO    18
+
+#define OTA_UART_CHUNK_SIZE  1024
+#define OTA_UART_ACK_TIMEOUT_MS  3000
+#define OTA_UART_MAX_RETRIES     3
+
+/* Frame type bytes */
+#define UART_OTA_BEGIN   0xC0u
+#define UART_OTA_DATA    0xC1u
+#define UART_OTA_END     0xC2u
+#define UART_OTA_ABORT   0xC3u
+#define UART_OTA_ACK     0xC4u
+#define UART_OTA_NACK    0xC5u
+#define UART_OTA_STATUS  0xC6u
+
+/* NACK error codes */
+#define OTA_ERR_BAD_CRC  0x01u
+#define OTA_ERR_WRITE    0x02u
+#define OTA_ERR_SIZE     0x03u
+
+typedef enum {
+    UART_OTA_S_IDLE        = 0,
+    UART_OTA_S_DOWNLOADING,  /* downloading from Gitea */
+    UART_OTA_S_SENDING,      /* sending to IO board */
+    UART_OTA_S_DONE,
+    UART_OTA_S_FAILED,
+} uart_ota_send_state_t;
+
+extern volatile uart_ota_send_state_t g_uart_ota_state;
+extern volatile uint8_t               g_uart_ota_progress;
+
+/* Trigger IO firmware update. Uses g_io_update (from gitea_ota).
+ * Downloads bin, then streams via UART. Returns false if busy or no update. */
+bool uart_ota_trigger(void);

esp32s3/balance/main/version.h

@@ -0,0 +1,14 @@
+#pragma once
+/* Embedded firmware version — bump on each release */
+#define BALANCE_FW_VERSION      "1.0.0"
+#define IO_FW_VERSION           "1.0.0"
+
+/* Gitea release tag prefixes */
+#define BALANCE_TAG_PREFIX      "esp32-balance/"
+#define IO_TAG_PREFIX           "esp32-io/"
+
+/* Gitea release asset filenames */
+#define BALANCE_BIN_ASSET       "balance-firmware.bin"
+#define IO_BIN_ASSET            "io-firmware.bin"
+#define BALANCE_SHA256_ASSET    "balance-firmware.sha256"
+#define IO_SHA256_ASSET         "io-firmware.sha256"

esp32s3/balance/main/vesc_can.c

@@ -0,0 +1,119 @@
+/* vesc_can.c — VESC CAN TWAI driver (bd-66hx)
+ *
+ * Receives VESC STATUS/4/5 frames via TWAI, proxies to Orin over serial.
+ * Transmits SET_RPM commands from Orin drive requests.
+ */
+
+#include "vesc_can.h"
+#include "orin_serial.h"
+#include "config.h"
+#include "driver/twai.h"
+#include "esp_log.h"
+#include "esp_timer.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include <string.h>
+
+static const char *TAG = "vesc_can";
+
+vesc_state_t g_vesc[2] = {0};
+
+/* Index for a given VESC node ID: 0=VESC_ID_A, 1=VESC_ID_B */
+static int vesc_idx(uint8_t id)
+{
+    if (id == VESC_ID_A) return 0;
+    if (id == VESC_ID_B) return 1;
+    return -1;
+}
+
+void vesc_can_init(void)
+{
+    twai_general_config_t gcfg = TWAI_GENERAL_CONFIG_DEFAULT(
+        (gpio_num_t)VESC_CAN_TX_GPIO,
+        (gpio_num_t)VESC_CAN_RX_GPIO,
+        TWAI_MODE_NORMAL);
+    gcfg.rx_queue_len = VESC_CAN_RX_QUEUE;
+
+    twai_timing_config_t  tcfg = TWAI_TIMING_CONFIG_500KBITS();
+    twai_filter_config_t  fcfg = TWAI_FILTER_CONFIG_ACCEPT_ALL();
+
+    ESP_ERROR_CHECK(twai_driver_install(&gcfg, &tcfg, &fcfg));
+    ESP_ERROR_CHECK(twai_start());
+    ESP_LOGI(TAG, "TWAI init OK: tx=%d rx=%d 500kbps", VESC_CAN_TX_GPIO, VESC_CAN_RX_GPIO);
+}
+
+void vesc_can_send_rpm(uint8_t vesc_id, int32_t erpm)
+{
+    uint32_t ext_id = ((uint32_t)VESC_PKT_SET_RPM << 8u) | vesc_id;
+    twai_message_t msg = {
+        .extd            = 1,
+        .identifier      = ext_id,
+        .data_length_code = 4,
+    };
+    uint32_t u = (uint32_t)erpm;
+    msg.data[0] = (uint8_t)(u >> 24u);
+    msg.data[1] = (uint8_t)(u >> 16u);
+    msg.data[2] = (uint8_t)(u >>  8u);
+    msg.data[3] = (uint8_t)(u);
+    twai_transmit(&msg, pdMS_TO_TICKS(5));
+}
+
+void vesc_can_rx_task(void *arg)
+{
+    QueueHandle_t tx_q = (QueueHandle_t)arg;
+    twai_message_t msg;
+
+    for (;;) {
+        if (twai_receive(&msg, pdMS_TO_TICKS(50)) != ESP_OK) {
+            continue;
+        }
+        if (!msg.extd) {
+            continue;  /* ignore standard frames */
+        }
+
+        uint8_t pkt_type = (uint8_t)(msg.identifier >> 8u);
+        uint8_t vesc_id  = (uint8_t)(msg.identifier & 0xFFu);
+        int idx = vesc_idx(vesc_id);
+        if (idx < 0) {
+            continue;  /* not our VESC */
+        }
+
+        uint32_t now_ms = (uint32_t)(esp_timer_get_time() / 1000LL);
+        vesc_state_t *s = &g_vesc[idx];
+
+        switch (pkt_type) {
+        case VESC_PKT_STATUS:
+            if (msg.data_length_code < 8u) { break; }
+            s->erpm = (int32_t)(
+                ((uint32_t)msg.data[0] << 24u) | ((uint32_t)msg.data[1] << 16u) |
+                ((uint32_t)msg.data[2] <<  8u) |  (uint32_t)msg.data[3]);
+            s->current_x10 = (int16_t)(((uint16_t)msg.data[4] << 8u) | msg.data[5]);
+            s->last_rx_ms  = now_ms;
+            /* Proxy to Orin: voltage from STATUS_5 (may be zero until received) */
+            {
+                uint8_t ttype = (vesc_id == VESC_ID_A) ? TELEM_VESC_LEFT : TELEM_VESC_RIGHT;
+                /* voltage_mv: V×10 → mV (/10 * 1000 = *100); current_ma: A×10 → mA (*100) */
+                uint16_t vmv = (uint16_t)((int32_t)s->voltage_x10 * 100);
+                int16_t  ima = (int16_t)((int32_t)s->current_x10 * 100);
+                orin_send_vesc(tx_q, ttype, s->erpm, vmv, ima,
+                               (uint16_t)s->temp_mot_x10);
+            }
+            break;
+
+        case VESC_PKT_STATUS_4:
+            if (msg.data_length_code < 6u) { break; }
+            /* T_fet×10, T_mot×10, I_in×10 */
+            s->temp_mot_x10 = (int16_t)(((uint16_t)msg.data[2] << 8u) | msg.data[3]);
+            break;
+
+        case VESC_PKT_STATUS_5:
+            if (msg.data_length_code < 6u) { break; }
+            /* int32 tacho (ignored), int16 V_in×10 */
+            s->voltage_x10 = (int16_t)(((uint16_t)msg.data[4] << 8u) | msg.data[5]);
+            break;
+
+        default:
+            break;
+        }
+    }
+}

esp32s3/balance/main/vesc_can.h

@@ -0,0 +1,36 @@
+#pragma once
+/* vesc_can.h — VESC CAN TWAI driver for ESP32-S3 BALANCE (bd-66hx)
+ *
+ * VESC extended CAN ID: (packet_type << 8) | vesc_node_id
+ * Physical layer: TWAI peripheral → SN65HVD230 → 500 kbps shared bus
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/queue.h"
+
+/* ── VESC packet types ── */
+#define VESC_PKT_SET_RPM    3u
+#define VESC_PKT_STATUS     9u    /* int32 erpm, int16 I×10, int16 duty×1000 */
+#define VESC_PKT_STATUS_4   16u   /* int16 T_fet×10, T_mot×10, I_in×10 */
+#define VESC_PKT_STATUS_5   27u   /* int32 tacho, int16 V_in×10 */
+
+/* ── VESC telemetry snapshot ── */
+typedef struct {
+    int32_t  erpm;          /* electrical RPM (STATUS) */
+    int16_t  current_x10;   /* phase current A×10 (STATUS) */
+    int16_t  voltage_x10;   /* bus voltage V×10 (STATUS_5) */
+    int16_t  temp_mot_x10;  /* motor temp °C×10 (STATUS_4) */
+    uint32_t last_rx_ms;    /* esp_timer ms of last STATUS frame */
+} vesc_state_t;
+
+/* ── Globals (two VESC nodes: index 0 = VESC_ID_A=56, 1 = VESC_ID_B=68) ── */
+extern vesc_state_t g_vesc[2];
+
+/* ── API ── */
+void vesc_can_init(void);
+void vesc_can_send_rpm(uint8_t vesc_id, int32_t erpm);
+
+/* RX task — pass tx_queue as arg; forwards STATUS frames to Orin over serial */
+void vesc_can_rx_task(void *arg);   /* arg = QueueHandle_t orin_tx_queue */

esp32s3/balance/partitions.csv

@@ -0,0 +1,7 @@
+# ESP32-S3 BALANCE — 4 MB flash, dual OTA partitions
+# Name,     Type,  SubType,  Offset,    Size
+nvs,        data,  nvs,      0x9000,    0x5000,
+otadata,    data,  ota,      0xe000,    0x2000,
+app0,       app,   ota_0,    0x10000,   0x1B0000,
+app1,       app,   ota_1,    0x1C0000,  0x1B0000,
+nvs_user,   data,  nvs,      0x370000,  0x50000,

esp32s3/balance/sdkconfig.defaults

@@ -0,0 +1,23 @@
+CONFIG_IDF_TARGET="esp32s3"
+CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y
+CONFIG_FREERTOS_HZ=1000
+CONFIG_ESP_TASK_WDT_EN=y
+CONFIG_ESP_TASK_WDT_TIMEOUT_S=5
+CONFIG_TWAI_ISR_IN_IRAM=y
+CONFIG_UART_ISR_IN_IRAM=y
+CONFIG_ESP_CONSOLE_UART_DEFAULT=y
+CONFIG_ESP_CONSOLE_UART_NUM=0
+CONFIG_ESP_CONSOLE_UART_BAUDRATE=115200
+CONFIG_LOG_DEFAULT_LEVEL_INFO=y
+
+# OTA — bd-3gwo: dual OTA partitions + rollback
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions.csv"
+CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y
+CONFIG_OTA_ALLOW_HTTP=y
+CONFIG_ESP_HTTPS_OTA_ALLOW_HTTP=y
+CONFIG_MBEDTLS_CERTIFICATE_BUNDLE=y
+
+# bd-66hx hardware: disable brownout detection — power supply dips during SPI/init
+# The gc9a01 display SPI init causes ~50mA transient that trips level-0 brownout
+CONFIG_ESP_BROWNOUT_DET=n

esp32s3/io/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.16)
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(esp32s3_io)

esp32s3/io/main/CMakeLists.txt

@@ -0,0 +1,10 @@
+idf_component_register(
+    SRCS "main.c" "uart_ota_recv.c"
+    INCLUDE_DIRS "."
+    REQUIRES
+        app_update
+        mbedtls
+        driver
+        freertos
+        esp_timer
+)

esp32s3/io/main/config.h

@@ -0,0 +1,35 @@
+#pragma once
+/* ESP32-S3 IO board — pin assignments (SAUL-TEE-SYSTEM-REFERENCE.md) */
+
+/* ── Inter-board UART (to/from BALANCE board) ── */
+#define IO_UART_PORT        UART_NUM_0
+#define IO_UART_BAUD        460800
+#define IO_UART_TX_GPIO     43   /* IO board UART0_TXD → BALANCE RX */
+#define IO_UART_RX_GPIO     44   /* IO board UART0_RXD ← BALANCE TX */
+/* Note: SAUL-TEE spec says IO TX=IO18, RX=IO21; BALANCE TX=IO17, RX=IO18.
+ * This is UART0 on the IO devkit (GPIO43/44). Adjust to match actual wiring. */
+
+/* ── BTS7960 Left motor driver ── */
+#define MOTOR_L_RPWM    1
+#define MOTOR_L_LPWM    2
+#define MOTOR_L_EN_R    3
+#define MOTOR_L_EN_L    4
+
+/* ── BTS7960 Right motor driver ── */
+#define MOTOR_R_RPWM    5
+#define MOTOR_R_LPWM    6
+#define MOTOR_R_EN_R    7
+#define MOTOR_R_EN_L    8
+
+/* ── Arming button / kill switch ── */
+#define ARM_BTN_GPIO    9
+#define KILL_GPIO       10
+
+/* ── WS2812B LED strip ── */
+#define LED_DATA_GPIO   13
+
+/* ── OTA UART — receives firmware from BALANCE (bd-21hv) ── */
+/* Uses same IO_UART_PORT since Balance drives OTA over the inter-board link */
+
+/* ── Firmware version ── */
+#define IO_FW_VERSION   "1.0.0"

esp32s3/io/main/main.c

@@ -0,0 +1,42 @@
+/* main.c — ESP32-S3 IO board app_main */
+
+#include "uart_ota_recv.h"
+#include "config.h"
+#include "esp_log.h"
+#include "esp_ota_ops.h"
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+static const char *TAG = "io_main";
+
+static void uart_init(void)
+{
+    uart_config_t cfg = {
+        .baud_rate  = IO_UART_BAUD,
+        .data_bits  = UART_DATA_8_BITS,
+        .parity     = UART_PARITY_DISABLE,
+        .stop_bits  = UART_STOP_BITS_1,
+        .flow_ctrl  = UART_HW_FLOWCTRL_DISABLE,
+    };
+    uart_param_config(IO_UART_PORT, &cfg);
+    uart_set_pin(IO_UART_PORT, IO_UART_TX_GPIO, IO_UART_RX_GPIO,
+                  UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE);
+    uart_driver_install(IO_UART_PORT, 4096, 0, 0, NULL, 0);
+}
+
+void app_main(void)
+{
+    ESP_LOGI(TAG, "ESP32-S3 IO v%s starting", IO_FW_VERSION);
+
+    /* Mark running image valid (OTA rollback support) */
+    esp_ota_mark_app_valid_cancel_rollback();
+
+    uart_init();
+    uart_ota_recv_init();
+
+    /* IO board main loop placeholder — RC/motor/sensor tasks added in later beads */
+    while (1) {
+        vTaskDelay(pdMS_TO_TICKS(1000));
+    }
+}

esp32s3/io/main/uart_ota_recv.c

@@ -0,0 +1,210 @@
+/* uart_ota_recv.c — IO board OTA receiver (bd-21hv)
+ *
+ * Listens on UART0 for OTA frames from Balance board.
+ * Writes incoming chunks to the inactive OTA partition, verifies SHA256,
+ * then reboots into new firmware.
+ */
+
+#include "uart_ota_recv.h"
+#include "config.h"
+#include "esp_log.h"
+#include "esp_ota_ops.h"
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "mbedtls/sha256.h"
+#include <string.h>
+
+static const char *TAG = "io_ota";
+
+volatile io_ota_state_t g_io_ota_state    = IO_OTA_IDLE;
+volatile uint8_t        g_io_ota_progress = 0;
+
+/* Frame type bytes (same as uart_ota.h sender side) */
+#define OTA_BEGIN   0xC0u
+#define OTA_DATA    0xC1u
+#define OTA_END     0xC2u
+#define OTA_ABORT   0xC3u
+#define OTA_ACK     0xC4u
+#define OTA_NACK    0xC5u
+
+#define CHUNK_MAX   1024
+
+static uint8_t crc8(const uint8_t *d, uint16_t len)
+{
+    uint8_t crc = 0;
+    for (uint16_t i = 0; i < len; i++) {
+        crc ^= d[i];
+        for (uint8_t b = 0; b < 8; b++)
+            crc = (crc & 0x80u) ? (uint8_t)((crc << 1u) ^ 0x07u) : (uint8_t)(crc << 1u);
+    }
+    return crc;
+}
+
+static void send_ack(uint16_t seq)
+{
+    uint8_t frame[6];
+    frame[0] = OTA_ACK;
+    frame[1] = (uint8_t)(seq >> 8u);
+    frame[2] = (uint8_t)(seq);
+    frame[3] = 0; frame[4] = 0;  /* LEN=0 */
+    uint8_t crc = crc8(frame, 5);
+    frame[5] = crc;
+    uart_write_bytes(IO_UART_PORT, (char *)frame, 6);
+}
+
+static void send_nack(uint16_t seq, uint8_t err)
+{
+    uint8_t frame[8];
+    frame[0] = OTA_NACK;
+    frame[1] = (uint8_t)(seq >> 8u);
+    frame[2] = (uint8_t)(seq);
+    frame[3] = 0; frame[4] = 1;  /* LEN=1 */
+    frame[5] = err;
+    uint8_t crc = crc8(frame, 6);
+    frame[6] = crc;
+    uart_write_bytes(IO_UART_PORT, (char *)frame, 7);
+}
+
+/* Read exact n bytes with timeout */
+static bool uart_read_exact(uint8_t *buf, int n, int timeout_ms)
+{
+    int got = 0;
+    while (got < n && timeout_ms > 0) {
+        int r = uart_read_bytes(IO_UART_PORT, buf + got, n - got,
+                                pdMS_TO_TICKS(50));
+        if (r > 0) got += r;
+        else timeout_ms -= 50;
+    }
+    return got == n;
+}
+
+static void ota_recv_task(void *arg)
+{
+    esp_ota_handle_t       handle    = 0;
+    const esp_partition_t *ota_part  = esp_ota_get_next_update_partition(NULL);
+    mbedtls_sha256_context sha;
+    mbedtls_sha256_init(&sha);
+    uint32_t expected_size = 0;
+    uint8_t  expected_digest[32] = {0};
+    uint32_t received = 0;
+    bool     ota_started = false;
+    static uint8_t payload[CHUNK_MAX];
+
+    for (;;) {
+        /* Read frame header: TYPE(1) + SEQ(2) + LEN(2) = 5 bytes */
+        uint8_t hdr[5];
+        if (!uart_read_exact(hdr, 5, 5000)) continue;
+
+        uint8_t  type = hdr[0];
+        uint16_t seq  = (uint16_t)((hdr[1] << 8u) | hdr[2]);
+        uint16_t plen = (uint16_t)((hdr[3] << 8u) | hdr[4]);
+
+        if (plen > CHUNK_MAX + 36) {
+            ESP_LOGW(TAG, "oversized frame plen=%u", plen);
+            continue;
+        }
+
+        /* Read payload + CRC */
+        if (plen > 0 && !uart_read_exact(payload, plen, 2000)) continue;
+        uint8_t crc_rx;
+        if (!uart_read_exact(&crc_rx, 1, 500)) continue;
+
+        /* Verify CRC over hdr+payload */
+        uint8_t crc_buf[5 + CHUNK_MAX + 36];
+        memcpy(crc_buf, hdr, 5);
+        if (plen > 0) memcpy(crc_buf + 5, payload, plen);
+        uint8_t expected_crc = crc8(crc_buf, (uint16_t)(5 + plen));
+        if (crc_rx != expected_crc) {
+            ESP_LOGW(TAG, "CRC fail seq=%u", seq);
+            send_nack(seq, 0x01u);  /* OTA_ERR_BAD_CRC */
+            continue;
+        }
+
+        switch (type) {
+        case OTA_BEGIN:
+            if (plen < 36) { send_nack(seq, 0x03u); break; }
+            expected_size = ((uint32_t)payload[0] << 24u) |
+                            ((uint32_t)payload[1] << 16u) |
+                            ((uint32_t)payload[2] <<  8u) |
+                             (uint32_t)payload[3];
+            memcpy(expected_digest, &payload[4], 32);
+
+            if (!ota_part || esp_ota_begin(ota_part, OTA_WITH_SEQUENTIAL_WRITES,
+                                            &handle) != ESP_OK) {
+                send_nack(seq, 0x02u);
+                break;
+            }
+            mbedtls_sha256_starts(&sha, 0);
+            received   = 0;
+            ota_started = true;
+            g_io_ota_state    = IO_OTA_RECEIVING;
+            g_io_ota_progress = 0;
+            ESP_LOGI(TAG, "OTA begin: %lu bytes", (unsigned long)expected_size);
+            send_ack(seq);
+            break;
+
+        case OTA_DATA:
+            if (!ota_started) { send_nack(seq, 0x02u); break; }
+            if (esp_ota_write(handle, payload, plen) != ESP_OK) {
+                send_nack(seq, 0x02u);
+                esp_ota_abort(handle);
+                ota_started = false;
+                g_io_ota_state = IO_OTA_FAILED;
+                break;
+            }
+            mbedtls_sha256_update(&sha, payload, plen);
+            received += plen;
+            if (expected_size > 0)
+                g_io_ota_progress = (uint8_t)((received * 100u) / expected_size);
+            send_ack(seq);
+            break;
+
+        case OTA_END: {
+            if (!ota_started) { send_nack(seq, 0x02u); break; }
+            g_io_ota_state = IO_OTA_VERIFYING;
+
+            uint8_t digest[32];
+            mbedtls_sha256_finish(&sha, digest);
+            if (memcmp(digest, expected_digest, 32) != 0) {
+                ESP_LOGE(TAG, "SHA256 mismatch");
+                esp_ota_abort(handle);
+                send_nack(seq, 0x01u);
+                g_io_ota_state = IO_OTA_FAILED;
+                break;
+            }
+
+            if (esp_ota_end(handle) != ESP_OK ||
+                esp_ota_set_boot_partition(ota_part) != ESP_OK) {
+                send_nack(seq, 0x02u);
+                g_io_ota_state = IO_OTA_FAILED;
+                break;
+            }
+
+            g_io_ota_state    = IO_OTA_REBOOTING;
+            g_io_ota_progress = 100;
+            ESP_LOGI(TAG, "OTA done — rebooting");
+            send_ack(seq);
+            vTaskDelay(pdMS_TO_TICKS(500));
+            esp_restart();
+            break;
+        }
+
+        case OTA_ABORT:
+            if (ota_started) { esp_ota_abort(handle); ota_started = false; }
+            g_io_ota_state = IO_OTA_IDLE;
+            ESP_LOGW(TAG, "OTA aborted");
+            break;
+
+        default:
+            break;
+        }
+    }
+}
+
+void uart_ota_recv_init(void)
+{
+    /* UART0 already initialized for inter-board comms; just create the task */
+    xTaskCreate(ota_recv_task, "io_ota_recv", 8192, NULL, 6, NULL);
+    ESP_LOGI(TAG, "OTA receiver task started");
+}

esp32s3/io/main/uart_ota_recv.h

@@ -0,0 +1,20 @@
+#pragma once
+/* uart_ota_recv.h — IO board: receives OTA firmware from Balance (bd-21hv) */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+typedef enum {
+    IO_OTA_IDLE       = 0,
+    IO_OTA_RECEIVING,
+    IO_OTA_VERIFYING,
+    IO_OTA_APPLYING,
+    IO_OTA_REBOOTING,
+    IO_OTA_FAILED,
+} io_ota_state_t;
+
+extern volatile io_ota_state_t g_io_ota_state;
+extern volatile uint8_t        g_io_ota_progress;
+
+/* Start listening for OTA frames on UART0 */
+void uart_ota_recv_init(void);

esp32s3/io/partitions.csv

@@ -0,0 +1,7 @@
+# ESP32-S3 IO — 4 MB flash, dual OTA partitions
+# Name,     Type,  SubType,  Offset,    Size
+nvs,        data,  nvs,      0x9000,    0x5000,
+otadata,    data,  ota,      0xe000,    0x2000,
+app0,       app,   ota_0,    0x10000,   0x1B0000,
+app1,       app,   ota_1,    0x1C0000,  0x1B0000,
+nvs_user,   data,  nvs,      0x370000,  0x50000,

esp32s3/io/sdkconfig.defaults

@@ -0,0 +1,13 @@
+CONFIG_IDF_TARGET="esp32s3"
+CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y
+CONFIG_FREERTOS_HZ=1000
+CONFIG_ESP_TASK_WDT_EN=y
+CONFIG_ESP_TASK_WDT_TIMEOUT_S=5
+CONFIG_UART_ISR_IN_IRAM=y
+CONFIG_ESP_CONSOLE_UART_DEFAULT=y
+CONFIG_LOG_DEFAULT_LEVEL_INFO=y
+
+# OTA — bd-3gwo: dual OTA partitions + rollback
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions.csv"
+CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y

jetson/README.md

@@ -6,15 +6,19 @@ Self-balancing robot: Jetson Orin Nano Super dev environment for ROS2 Humble + S
 
 | Component | Version / Part |
 |-----------|---------------|
-| Platform | Jetson Orin Nano Super 8GB |
-| JetPack | 6.x (L4T R36.x, CUDA 12.x) |
+| Platform | Jetson Orin Nano Super 4GB |
+| JetPack | 4.6 (L4T R32.6.1, CUDA 10.2) |
 | ROS2 | Humble Hawksbill |
 | DDS | CycloneDDS |
 | SLAM | slam_toolbox |
 | Nav | Nav2 |
 | Depth camera | Intel RealSense D435i |
 | LiDAR | RPLIDAR A1M8 |
-| MCU bridge | ESP32-S3 BALANCE (CAN bus @ 500 kbps via CANable 2.0) |
+<<<<<<< HEAD
+| MCU bridge | ESP32 (USB CDC @ 921600) |
+=======
+| MCU bridge | ESP32-S3 (USB Serial (CH343) @ 921600) |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ## Quick Start
 
@@ -42,11 +46,15 @@ bash scripts/build-and-run.sh shell
 ```
 jetson/
 ├── Dockerfile              # L4T base + ROS2 Humble + SLAM packages
-├── docker-compose.yml      # Multi-service stack (ROS2, RPLIDAR, D435i, CAN bridge)
+<<<<<<< HEAD
+├── docker-compose.yml      # Multi-service stack (ROS2, RPLIDAR, D435i, ESP32 BALANCE)
+=======
+├── docker-compose.yml      # Multi-service stack (ROS2, RPLIDAR, D435i, ESP32-S3)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 ├── README.md               # This file
 ├── docs/
 │   ├── pinout.md           # GPIO/I2C/UART pinout reference
-│   └── power-budget.md     # Power budget analysis (25W envelope)
+│   └── power-budget.md     # Power budget analysis (10W envelope)
 └── scripts/
     ├── entrypoint.sh       # Docker container entrypoint
     ├── setup-jetson.sh     # Host setup (udev, Docker, nvpmodel)
@@ -58,8 +66,8 @@ jetson/
 | Scenario | Total |
 |---------|-------|
 | Idle | 2.9W |
-| Nominal (SLAM active) | ~19.9W |
-| Peak | ~28.2W |
+| Nominal (SLAM active) | ~10.2W |
+| Peak | 15.4W |
 
-Target: 25W (MAXN nvpmodel). 5W headroom at nominal load.
+Target: 10W (MAXN nvpmodel). Use RPLIDAR standby + 640p D435i for compliance.
 See [`docs/power-budget.md`](docs/power-budget.md) for full analysis.

jetson/config/RECOVERY_BEHAVIORS.md

@@ -10,7 +10,7 @@ Recovery behaviors are triggered when Nav2 encounters navigation failures (path
 
 ### Backup Recovery (Issue #479)
 - **Distance**: 0.3 meters reverse
-- **Speed**: 0.1 m/s (very conservative for ESP32-S3 BALANCE + VESC)
+- **Speed**: 0.1 m/s (very conservative for FC + Hoverboard ESC)
 - **Max velocity**: 0.15 m/s (absolute limit)
 - **Time limit**: 5 seconds maximum
 
@@ -34,16 +34,20 @@ Recovery behaviors are triggered when Nav2 encounters navigation failures (path
 
 The emergency stop system (Issue #459, `saltybot_emergency` package) runs independently of Nav2 and takes absolute priority.
 
-Recovery behaviors cannot interfere with E-stop because the emergency system operates at the motor driver level on the ESP32-S3 BALANCE firmware.
+<<<<<<< HEAD
+Recovery behaviors cannot interfere with E-stop because the emergency system operates at the motor driver level on the ESP32 BALANCE firmware.
+=======
+Recovery behaviors cannot interfere with E-stop because the emergency system operates at the motor driver level on the ESP32-S3 firmware.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ## Behavior Tree Sequence
 
 Recovery runs in a round-robin fashion with up to 6 retry cycles.
 
-## Constraints for ESP32-S3 BALANCE + VESC
+## Constraints for FC + Hoverboard ESC
 
 This configuration is specifically tuned for:
-- **Drivetrain**: ESP32-S3 BALANCE + VESC (CAN bus)
+- **Drivetrain**: Flux Capacitor (FC) balancing controller + Hoverboard brushless ESC
 - **Max linear velocity**: 1.0 m/s
 - **Max angular velocity**: 1.5 rad/s
 - **Recovery velocity constraints**: 50% of normal for stability

jetson/docker-compose.yml

@@ -97,11 +97,7 @@ services:
           rgb_camera.profile:=640x480x30
       "
 
-<<<<<<< HEAD
-  # ── ESP32 bridge node (bidirectional serial<->ROS2) ────────────────────────
-=======
-  # ── ESP32-S3 bridge node (bidirectional serial<->ROS2) ────────────────────────
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+  # ── ESP32-S3 bridge node (bidirectional serial<->ROS2) ───────────────────────
   esp32-bridge:
     image: saltybot/ros2-humble:jetson-orin
     build:
@@ -212,13 +208,8 @@ services:
       "
 
 
-<<<<<<< HEAD
-  # -- Remote e-stop bridge (MQTT over 4G -> ESP32 CDC) ----------------------
-  # Subscribes to saltybot/estop MQTT topic. {"kill":true} -> 'E\r\n' to ESP32 BALANCE.
-=======
-  # -- Remote e-stop bridge (MQTT over 4G -> ESP32-S3 CDC) ----------------------
+  # -- Remote e-stop bridge (MQTT over 4G -> ESP32-S3 CDC) ---------------------
   # Subscribes to saltybot/estop MQTT topic. {"kill":true} -> 'E\r\n' to ESP32-S3.
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   # Cellular watchdog: 5s MQTT drop in AUTO mode -> 'F\r\n' (ESTOP_CELLULAR_TIMEOUT).
   remote-estop:
     image: saltybot/ros2-humble:jetson-orin
@@ -366,6 +357,50 @@ services:
       "
 
 
+  # ── Here4 DroneCAN GPS + NTRIP RTK client ────────────────────────────────
+  # Issue #725 — CubePilot Here4 RTK GPS via DroneCAN (1Mbps, SocketCAN)
+  # Start: docker compose up -d here4-gps
+  # Monitor fix: docker compose exec here4-gps ros2 topic echo /gps/rtk_status
+  # Configure NTRIP: set NTRIP_MOUNT, NTRIP_USER, NTRIP_PASSWORD env vars
+  here4-gps:
+    image: saltybot/ros2-humble:jetson-orin
+    build:
+      context: .
+      dockerfile: Dockerfile
+    container_name: saltybot-here4-gps
+    restart: unless-stopped
+    runtime: nvidia
+    network_mode: host
+    depends_on:
+      - saltybot-nav2
+    environment:
+      - ROS_DOMAIN_ID=42
+      - RMW_IMPLEMENTATION=rmw_cyclonedds_cpp
+      # NTRIP credentials — set these in your .env or override at runtime
+      - NTRIP_MOUNT=${NTRIP_MOUNT:-}
+      - NTRIP_USER=${NTRIP_USER:-}
+      - NTRIP_PASSWORD=${NTRIP_PASSWORD:-}
+    volumes:
+      - ./ros2_ws/src:/ros2_ws/src:rw
+      - ./config:/config:ro
+    devices:
+      - /dev/can0:/dev/can0
+    cap_add:
+      - NET_ADMIN    # needed for SocketCAN ip link set can0 up inside container
+    command: >
+      bash -c "
+        source /opt/ros/humble/setup.bash &&
+        source /ros2_ws/install/local_setup.bash 2>/dev/null || true &&
+        pip install python-dronecan --quiet 2>/dev/null || true &&
+        ros2 launch saltybot_dronecan_gps here4_gps.launch.py
+          can_interface:=can0
+          can_bitrate:=1000000
+          ntrip_caster:=rtk2go.com
+          ntrip_mount:=${NTRIP_MOUNT:-}
+          ntrip_user:=${NTRIP_USER:-}
+          ntrip_password:=${NTRIP_PASSWORD:-}
+      "
+
 volumes:
   saltybot-maps:
     driver: local

jetson/docs/pinout.md

@@ -1,5 +1,9 @@
 # Jetson Orin Nano Super — GPIO / I2C / UART / CSI Pinout Reference
-## Self-Balancing Robot: ESP32-S3 BALANCE (CAN bus) + RealSense D435i + RPLIDAR A1M8 + 4× IMX219
+<<<<<<< HEAD
+## Self-Balancing Robot: ESP32 Bridge + RealSense D435i + RPLIDAR A1M8 + 4× IMX219
+=======
+## Self-Balancing Robot: ESP32-S3 Bridge + RealSense D435i + RPLIDAR A1M8 + 4× IMX219
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 Last updated: 2026-02-28
 JetPack version: 6.x (L4T R36.x / Ubuntu 22.04)
@@ -43,36 +47,75 @@ i2cdetect -l
 
 ---
 
-## 1. ESP32-S3 BALANCE Bridge (CAN bus — Primary)
+<<<<<<< HEAD
+## 1. ESP32 Bridge (USB CDC — Primary)
 
-The ESP32-S3 BALANCE acts as a real-time motor + IMU controller. Communication is via **CAN bus** through a CANable 2.0 USB-CAN adapter.
+The ESP32 BALANCE acts as a real-time motor + IMU controller. Communication is via **USB CDC serial**.
+=======
+## 1. ESP32-S3 Bridge (USB Serial (CH343) — Primary)
 
-### CAN Bus Connection
+The ESP32-S3 acts as a real-time motor + IMU controller. Communication is via **USB Serial (CH343) serial**.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+
+### USB Serial (CH343) Connection
 | Connection | Detail |
 |-----------|--------|
-| Interface | CANable 2.0 USB-CAN adapter → USB-A on Jetson |
-| Device node | `/dev/can0` (via CANable 2.0, SocketCAN) |
-| Bitrate | 500 kbps |
-| Protocol | Binary CAN frames (see balance_protocol.py) |
-| Power | ESP32-S3 BALANCE powered from robot 5V DC-DC |
+<<<<<<< HEAD
+| Interface | USB on ESP32 BALANCE board → USB-A on Jetson |
+| Device node | `/dev/ttyACM0` → symlink `/dev/esp32-bridge` (via udev) |
+| Baud rate | 921600 (configured in ESP32 BALANCE firmware) |
+=======
+| Interface | USB Micro-B on ESP32-S3 dev board → USB-A on Jetson |
+| Device node | `/dev/ttyACM0` → symlink `/dev/esp32-bridge` (via udev) |
+| Baud rate | 921600 (configured in ESP32-S3 firmware) |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+| Protocol | JSON telemetry RX + ASCII command TX (see bridge docs) |
+| Power | Powered via robot 5V bus (data-only via USB) |
+
+### Hardware UART (Fallback — 40-pin header)
+<<<<<<< HEAD
+| Jetson Pin | Signal | ESP32 Pin | Notes |
+=======
+| Jetson Pin | Signal | ESP32-S3 Pin | Notes |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+|-----------|--------|-----------|-------|
+| Pin 8 (TXD0) | TX → | PA10 (UART1 RX) | Cross-connect TX→RX |
+| Pin 10 (RXD0) | RX ← | PA9 (UART1 TX) | Cross-connect RX→TX |
+| Pin 6 (GND) | GND | GND | Common ground **required** |
+
+**Jetson device node:** `/dev/ttyTHS0`
+**Baud rate:** 921600, 8N1
+<<<<<<< HEAD
+**Voltage level:** 3.3V — both Jetson Orin and ESP32 are 3.3V GPIO
+=======
+**Voltage level:** 3.3V — both Jetson Orin and ESP32-S3 are 3.3V GPIO
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
-### Bring Up CAN Interface
 ```bash
-# Bring up can0 at 500 kbps
-sudo ip link set can0 up type can bitrate 500000
-ip link show can0
-
-# Quick test — dump CAN frames
-candump can0
+# Verify UART
+ls /dev/ttyTHS0
+sudo usermod -aG dialout $USER
+# Quick test
+picocom -b 921600 /dev/ttyTHS0
 ```
 
-**ROS2 topics (CAN bridge node):**
+<<<<<<< HEAD
+**ROS2 topics (ESP32 bridge node):**
+| ROS2 Topic | Direction | Content |
+|-----------|-----------|---------
+| `/saltybot/imu` | ESP32 BALANCE→Jetson | IMU data (accel, gyro) at 50Hz |
+| `/saltybot/balance_state` | ESP32 BALANCE→Jetson | Motor cmd, pitch, state |
+| `/cmd_vel` | Jetson→ESP32 BALANCE | Velocity commands → `C<spd>,<str>\n` |
+| `/saltybot/estop` | Jetson→ESP32 BALANCE | Emergency stop |
+=======
+**ROS2 topics (ESP32-S3 bridge node):**
 | ROS2 Topic | Direction | Content |
 |-----------|-----------|---------
 | `/saltybot/imu` | ESP32-S3→Jetson | IMU data (accel, gyro) at 50Hz |
 | `/saltybot/balance_state` | ESP32-S3→Jetson | Motor cmd, pitch, state |
-| `/cmd_vel` | Jetson→CAN 0x300 | Velocity commands via CAN |
-| `/saltybot/estop` | Jetson→CAN 0x302 | Emergency stop |
+| `/cmd_vel` | Jetson→ESP32-S3 | Velocity commands → `C<spd>,<str>\n` |
+| `/saltybot/estop` | Jetson→ESP32-S3 | Emergency stop |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 ---
 
@@ -257,7 +300,11 @@ sudo mkdir -p /mnt/nvme
 |------|------|----------|
 | USB-A (top, blue) | USB 3.1 Gen 1 | RealSense D435i |
 | USB-A (bottom) | USB 2.0 | RPLIDAR (via USB-UART adapter) |
-| USB-C | USB 3.1 Gen 1 (+ DP) | CANable 2.0 or host flash |
+<<<<<<< HEAD
+| USB-C | USB 3.1 Gen 1 (+ DP) | ESP32 CDC or host flash |
+=======
+| USB-C | USB 3.1 Gen 1 (+ DP) | ESP32-S3 CDC or host flash |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | Micro-USB | Debug/flash | JetPack flash only |
 
 ---
@@ -268,10 +315,17 @@ sudo mkdir -p /mnt/nvme
 |-------------|----------|---------|----------|
 | 3 | SDA1 | 3.3V | I2C data (i2c-7) |
 | 5 | SCL1 | 3.3V | I2C clock (i2c-7) |
-| 8 | TXD0 | 3.3V | UART TX → ESP32-S3 IO (inter-board, fallback) |
-| 10 | RXD0 | 3.3V | UART RX ← ESP32-S3 IO (inter-board, fallback) |
+<<<<<<< HEAD
+| 8 | TXD0 | 3.3V | UART TX → ESP32 BALANCE (fallback) |
+| 10 | RXD0 | 3.3V | UART RX ← ESP32 BALANCE (fallback) |
 | USB-A ×2 | — | 5V | D435i, RPLIDAR |
-| USB-C | — | 5V | CANable 2.0 (CAN bus) |
+| USB-C | — | 5V | ESP32 CDC |
+=======
+| 8 | TXD0 | 3.3V | UART TX → ESP32-S3 (fallback) |
+| 10 | RXD0 | 3.3V | UART RX ← ESP32-S3 (fallback) |
+| USB-A ×2 | — | 5V | D435i, RPLIDAR |
+| USB-C | — | 5V | ESP32-S3 CDC |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | CSI-A (J5) | MIPI CSI-2 | — | Cameras front + left |
 | CSI-B (J8) | MIPI CSI-2 | — | Cameras rear + right |
 | M.2 Key M | PCIe Gen3 ×4 | — | NVMe SSD |
@@ -289,10 +343,13 @@ Apply stable device names:
 KERNEL=="ttyUSB*", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", \
   SYMLINK+="rplidar", MODE="0666"
 
-# CANable 2.0 USB-CAN adapter
-# (bring up with: sudo ip link set can0 up type can bitrate 500000)
+<<<<<<< HEAD
+# ESP32 USB CDC (STMicroelectronics)
+=======
+# ESP32-S3 USB Serial (CH343) (STMicroelectronics)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 KERNEL=="ttyACM*", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="5740", \
-  SYMLINK+="balance", MODE="0666"
+  SYMLINK+="esp32-bridge", MODE="0666"
 
 # Intel RealSense D435i
 SUBSYSTEM=="usb", ATTRS{idVendor}=="8086", ATTRS{idProduct}=="0b3a", \

jetson/docs/power-budget.md

@@ -56,7 +56,11 @@ sudo jtop
 |-----------|----------|------------|----------|-----------|-------|
 | RealSense D435i | 0.3 | 1.5 | 3.5 | USB 3.1 | Peak during boot/init |
 | RPLIDAR A1M8 | 0.4 | 2.6 | 3.0 | USB (UART adapter) | Motor spinning |
-| ESP32-S3 BALANCE | 0.5 | 0.5 | 0.5 | CAN bus (SN65HVD230) | Powered from 5V DC-DC |
+<<<<<<< HEAD
+| ESP32 bridge | 0.0 | 0.0 | 0.0 | USB CDC | Self-powered from robot 5V |
+=======
+| ESP32-S3 bridge | 0.0 | 0.0 | 0.0 | USB Serial (CH343) | Self-powered from robot 5V |
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 | 4× IMX219 cameras | 0.2 | 2.0 | 2.4 | MIPI CSI-2 | ~0.5W per camera active |
 | **Peripheral Subtotal** | **0.9** | **6.1** | **8.9** | | |
 
@@ -72,7 +76,7 @@ sudo jtop
 
 ## Budget Analysis vs Previous Platform
 
-| Metric | Jetson Nano | Jetson Orin Nano Super |
+| Metric | Jetson Orin Nano Super | Jetson Orin Nano Super |
 |--------|------------|------------------------|
 | TDP | 10W | 25W |
 | CPU | 4× Cortex-A57 @ 1.43GHz | 6× A78AE @ 1.5GHz |
@@ -151,9 +155,13 @@ LiPo 4S (16.8V max)
        ├─► DC-DC Buck → 5V 6A ──► Jetson Orin barrel jack (30W)
        │   (e.g., XL4016E1)
        │
-       ├─► DC-DC Buck → 5V 3A ──► ESP32-S3 BALANCE + ESP32-S3 IO + logic 5V rail
+<<<<<<< HEAD
+       ├─► DC-DC Buck → 5V 3A ──► ESP32 + logic 5V rail
+=======
+       ├─► DC-DC Buck → 5V 3A ──► ESP32-S3 + logic 5V rail
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
        │
-       └─► VESC left (ID 68) + VESC right (ID 56) ──► Hub motors
+       └─► Hoverboard ESC ──► Hub motors (48V loop)
 ```
 
 Using a 4S LiPo (vs 3S previously) gives better efficiency for the 5V buck converter

jetson/nginx/saul-tee.conf

@@ -0,0 +1,64 @@
+# saul-tee.conf — nginx site for saul-t-mote.evthings.app reverse proxy
+#
+# Replaces: python3 -m http.server 8080 --directory /home/seb
+# Router (ASUS Merlin / OpenResty) terminates TLS on :443 and proxies to Orin:8080
+#
+# Deploy:
+#   sudo cp saul-tee.conf /etc/nginx/sites-available/saul-tee
+#   sudo ln -sf /etc/nginx/sites-available/saul-tee /etc/nginx/sites-enabled/saul-tee
+#   sudo systemctl reload nginx
+#
+# ROUTER REQUIREMENT for WSS to work:
+#   The ASUS Merlin router's nginx/OpenResty must proxy /rosbridge with
+#   WebSocket headers.  Add to /jffs/configs/nginx.conf.add:
+#
+#     map $http_upgrade $connection_upgrade {
+#         default upgrade;
+#         ''      close;
+#     }
+#
+#   And in the server block that proxies to 192.168.86.158:8080, add:
+#
+#     location /rosbridge {
+#         proxy_pass         http://192.168.86.158:8080/rosbridge;
+#         proxy_http_version 1.1;
+#         proxy_set_header   Upgrade    $http_upgrade;
+#         proxy_set_header   Connection $connection_upgrade;
+#         proxy_read_timeout 86400;
+#     }
+
+# Infer WebSocket upgrade from Connection header.
+# Handles the case where an upstream proxy (e.g. ASUS Merlin OpenResty)
+# passes Connection: upgrade but strips the Upgrade: websocket header.
+map $http_connection $ws_upgrade {
+    "upgrade" "websocket";
+    default   "";
+}
+
+server {
+    listen 8080 default_server;
+    listen [::]:8080 default_server;
+
+    root /home/seb;
+    index index.html;
+    server_name _;
+
+    # Static files — replaces python3 -m http.server 8080 --directory /home/seb
+    location / {
+        try_files $uri $uri/ =404;
+        autoindex on;
+    }
+
+    # rosbridge WebSocket reverse proxy
+    # wss://saul-t-mote.evthings.app/rosbridge  -->  ws://127.0.0.1:9090
+    location /rosbridge {
+        proxy_pass         http://127.0.0.1:9090/;
+        proxy_http_version 1.1;
+        proxy_set_header   Upgrade    $ws_upgrade;
+        proxy_set_header   Connection "upgrade";
+        proxy_set_header   Host       $host;
+        proxy_set_header   X-Real-IP  $remote_addr;
+        proxy_read_timeout 86400;
+        proxy_send_timeout 86400;
+    }
+}

jetson/ros2_ws/src/saltybot_bridge/launch/uart_bridge.launch.py

@@ -2,7 +2,11 @@
 uart_bridge.launch.py — FC↔Orin UART bridge (Issue #362)
 
 Launches serial_bridge_node configured for Jetson Orin UART port.
-Bridges ESP32-S3 BALANCE telemetry from inter-board UART into ROS2.
+<<<<<<< HEAD
+Bridges Flight Controller (ESP32) telemetry from /dev/ttyTHS1 into ROS2.
+=======
+Bridges Flight Controller (ESP32-S3) telemetry from /dev/ttyTHS1 into ROS2.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 Published topics (same as USB CDC bridge):
   /saltybot/imu              sensor_msgs/Imu         — pitch/roll/yaw as angular velocity
@@ -20,7 +24,11 @@ Usage:
 
 Prerequisites:
   - Flight Controller connected to /dev/ttyTHS1 @ 921600 baud
-  - STM32 firmware transmitting JSON telemetry frames (50 Hz)
+<<<<<<< HEAD
+  - ESP32 BALANCE firmware transmitting JSON telemetry frames (50 Hz)
+=======
+  - ESP32-S3 firmware transmitting JSON telemetry frames (50 Hz)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   - ROS2 environment sourced (source install/setup.bash)
 
 Note:

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/cmd_vel_bridge_node.py

@@ -1,5 +1,9 @@
 """
-cmd_vel_bridge_node — Nav2 /cmd_vel → STM32 drive command bridge.
+<<<<<<< HEAD
+cmd_vel_bridge_node — Nav2 /cmd_vel → ESP32 BALANCE drive command bridge.
+=======
+cmd_vel_bridge_node — Nav2 /cmd_vel → ESP32-S3 drive command bridge.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 Extends the basic saltybot_cmd_node with four additions required for safe
 autonomous operation on a self-balancing robot:
@@ -12,7 +16,11 @@ autonomous operation on a self-balancing robot:
   3. Deadman switch    — if /cmd_vel is silent for cmd_vel_timeout seconds,
                          zero targets immediately (Nav2 node crash / planner
                          stall → robot coasts to stop rather than running away).
-  4. Mode gate         — only issue non-zero drive commands when STM32 reports
+<<<<<<< HEAD
+  4. Mode gate         — only issue non-zero drive commands when ESP32 BALANCE reports
+=======
+  4. Mode gate         — only issue non-zero drive commands when ESP32-S3 reports
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
                          md=2 (AUTONOMOUS). In any other mode (RC_MANUAL,
                          RC_ASSISTED) Jetson cannot override the RC pilot.
                          On mode re-entry current ramp state resets to 0 so
@@ -20,9 +28,15 @@ autonomous operation on a self-balancing robot:
 
 Serial protocol (C<speed>,<steer>\\n / H\\n — same as saltybot_cmd_node):
   C<spd>,<str>\\n  — drive command. speed/steer: -1000..+1000 integers.
-  H\\n             — heartbeat. STM32 reverts steer to 0 after 500ms silence.
+<<<<<<< HEAD
+  H\\n             — heartbeat. ESP32 BALANCE reverts steer to 0 after 500ms silence.
 
-Telemetry (50 Hz from STM32):
+Telemetry (50 Hz from ESP32 BALANCE):
+=======
+  H\\n             — heartbeat. ESP32-S3 reverts steer to 0 after 500ms silence.
+
+Telemetry (50 Hz from ESP32-S3):
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   Same RX/publish pipeline as saltybot_cmd_node.
   The "md" field (0=MANUAL,1=ASSISTED,2=AUTO) is parsed for the mode gate.
 
@@ -134,7 +148,7 @@ class CmdVelBridgeNode(Node):
         self._current_speed = 0   # ramped output actually sent
         self._current_steer = 0
         self._last_cmd_vel  = 0.0 # wall clock (seconds) of last /cmd_vel msg
-        self._stm32_mode    = 0   # parsed "md" field: 0=MANUAL,1=ASSISTED,2=AUTO
+        self._esp32_mode    = 0   # parsed "md" field: 0=MANUAL,1=ASSISTED,2=AUTO
         self._last_state    = -1
         self._frame_count   = 0
         self._error_count   = 0
@@ -150,7 +164,11 @@ class CmdVelBridgeNode(Node):
         self._open_serial()
 
         # ── Timers ────────────────────────────────────────────────────────────
-        # Telemetry read at 100 Hz (STM32 sends at 50 Hz)
+<<<<<<< HEAD
+        # Telemetry read at 100 Hz (ESP32 BALANCE sends at 50 Hz)
+=======
+        # Telemetry read at 100 Hz (ESP32-S3 sends at 50 Hz)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         self._read_timer    = self.create_timer(0.01,             self._read_cb)
         # Control loop at 50 Hz: ramp + deadman + mode gate + send
         self._control_timer = self.create_timer(1.0 / _CONTROL_HZ, self._control_cb)
@@ -225,7 +243,7 @@ class CmdVelBridgeNode(Node):
 
         # Mode gate: in non-AUTONOMOUS mode, zero and reset ramp state so
         # re-entry always accelerates smoothly from 0.
-        if self._stm32_mode != MODE_AUTONOMOUS:
+        if self._esp32_mode != MODE_AUTONOMOUS:
             self._current_speed = 0
             self._current_steer = 0
             speed, steer = 0, 0
@@ -238,7 +256,11 @@ class CmdVelBridgeNode(Node):
             speed = self._current_speed
             steer = self._current_steer
 
-        # Send to STM32
+<<<<<<< HEAD
+        # Send to ESP32 BALANCE
+=======
+        # Send to ESP32-S3
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         frame = f"C{speed},{steer}\n".encode("ascii")
         if not self._write(frame):
             self.get_logger().warn(
@@ -256,7 +278,11 @@ class CmdVelBridgeNode(Node):
     # ── Heartbeat TX ──────────────────────────────────────────────────────────
 
     def _heartbeat_cb(self):
-        """H\\n keeps STM32 jetson_cmd heartbeat alive regardless of mode."""
+<<<<<<< HEAD
+        """H\\n keeps ESP32 BALANCE jetson_cmd heartbeat alive regardless of mode."""
+=======
+        """H\\n keeps ESP32-S3 jetson_cmd heartbeat alive regardless of mode."""
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         self._write(b"H\n")
 
     # ── Telemetry RX ──────────────────────────────────────────────────────────
@@ -319,7 +345,7 @@ class CmdVelBridgeNode(Node):
         state     = int(data["s"])
         mode      = int(data.get("md", 0))  # 0=MANUAL if not present
 
-        self._stm32_mode = mode
+        self._esp32_mode = mode
         self._frame_count += 1
 
         self._publish_imu(pitch_deg, roll_deg, yaw_deg, now)
@@ -378,7 +404,11 @@ class CmdVelBridgeNode(Node):
         diag.header.stamp = stamp
         status = DiagnosticStatus()
         status.name        = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
+=======
+        status.hardware_id = "esp32s322"
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         status.message     = f"{state_label} [{mode_label}]"
         status.level = (
             DiagnosticStatus.OK    if state == 1 else
@@ -406,11 +436,19 @@ class CmdVelBridgeNode(Node):
         status = DiagnosticStatus()
         status.level       = DiagnosticStatus.ERROR
         status.name        = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
         status.message     = f"IMU fault errno={errno}"
         diag.status.append(status)
         self._diag_pub.publish(diag)
-        self.get_logger().error(f"STM32 IMU fault: errno={errno}")
+        self.get_logger().error(f"ESP32 BALANCE IMU fault: errno={errno}")
+=======
+        status.hardware_id = "esp32s322"
+        status.message     = f"IMU fault errno={errno}"
+        diag.status.append(status)
+        self._diag_pub.publish(diag)
+        self.get_logger().error(f"ESP32-S3 IMU fault: errno={errno}")
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
     # ── Lifecycle ─────────────────────────────────────────────────────────────
 

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py

@@ -1,45 +1,66 @@
-"""esp32_cmd_node.py — Full bidirectional binary-framed ESP32-S3 BALANCE↔Jetson bridge.
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+"""stm32_cmd_node.py — Orin ↔ ESP32-S3 IO auxiliary bridge node.
+=======
+"""esp32_cmd_node.py — Full bidirectional binary-framed ESP32-S3↔Jetson bridge.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 
-Issue #119: replaces the ASCII-protocol saltybot_cmd_node with a robust binary
-framing protocol (STX/TYPE/LEN/PAYLOAD/CRC16/ETX) at 460800 baud (inter-board UART).
+Connects to the ESP32-S3 IO board via USB-CDC (/dev/esp32-io) using the
+inter-board binary protocol (docs/SAUL-TEE-SYSTEM-REFERENCE.md §5).
 
-TX commands (Jetson → ESP32-S3 BALANCE):
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+This node is NOT the primary drive path (that is CAN via can_bridge_node).
+It handles auxiliary I/O: RC monitoring, sensor data, LED/output control.
+=======
+TX commands (Jetson → ESP32-S3):
   SPEED_STEER  — 50 Hz from /cmd_vel subscription
-  HEARTBEAT    — 200 ms timer (ESP32-S3 BALANCE watchdog fires at 500 ms)
+  HEARTBEAT    — 200 ms timer (ESP32-S3 watchdog fires at 500 ms)
   ARM          — via /saltybot/arm service
   SET_MODE     — via /saltybot/set_mode service
   PID_UPDATE   — via /saltybot/pid_update topic
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 
-Watchdog: if /cmd_vel is silent for 500 ms, send SPEED_STEER(0,0) and log warning.
+Frame format: [0xAA][LEN][TYPE][PAYLOAD][CRC8]  @ 460800 baud
 
-RX telemetry (ESP32-S3 BALANCE → Jetson):
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+RX from ESP32 IO:
+  RC_CHANNELS (0x01) → /saltybot/rc_channels  (std_msgs/String JSON)
+  SENSORS     (0x02) → /saltybot/sensors       (std_msgs/String JSON)
+=======
+RX telemetry (ESP32-S3 → Jetson):
   IMU          → /saltybot/imu           (sensor_msgs/Imu)
   BATTERY      → /saltybot/telemetry/battery (std_msgs/String JSON)
   MOTOR_RPM    → /saltybot/telemetry/motor_rpm (std_msgs/String JSON)
   ARM_STATE    → /saltybot/arm_state     (std_msgs/String JSON)
   ERROR        → /saltybot/error         (std_msgs/String JSON)
   All frames   → /diagnostics            (diagnostic_msgs/DiagnosticArray)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 
-Auto-reconnect: USB disconnect is detected when serial.read() raises; node
-continuously retries at reconnect_delay interval.
+TX to ESP32 IO:
+  LED_CMD     (0x10) ← /saltybot/leds          (std_msgs/String JSON)
+  OUTPUT_CMD  (0x11) ← /saltybot/outputs       (std_msgs/String JSON)
+  HEARTBEAT   (0x20)  — sent every heartbeat_period (keep IO watchdog alive)
 
-This node owns /dev/can0 exclusively — do NOT run alongside
-serial_bridge_node or saltybot_cmd_node on the same port.
-
-Parameters (config/esp32_cmd_params.yaml):
-  serial_port       /dev/can0
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+Parameters (config/stm32_cmd_params.yaml):
+  serial_port       /dev/esp32-io
   baud_rate         460800
+  reconnect_delay   2.0
+  heartbeat_period  0.2   (ESP32 IO watchdog fires at ~500 ms)
+=======
+Parameters (config/esp32_cmd_params.yaml):
+  serial_port       /dev/ttyACM0
+  baud_rate         921600
   reconnect_delay   2.0   (seconds)
   heartbeat_period  0.2   (seconds)
   watchdog_timeout  0.5   (seconds — no /cmd_vel → send zero-speed)
   speed_scale       1000.0 (linear.x m/s → ESC units)
   steer_scale      -500.0  (angular.z rad/s → ESC units, neg to flip convention)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 """
 
 from __future__ import annotations
 
 import json
-import math
 import threading
 import time
 
@@ -50,119 +71,82 @@ from rclpy.qos import HistoryPolicy, QoSProfile, ReliabilityPolicy
 import serial
 
 from diagnostic_msgs.msg import DiagnosticArray, DiagnosticStatus, KeyValue
-from geometry_msgs.msg import Twist
-from sensor_msgs.msg import Imu
 from std_msgs.msg import String
-from std_srvs.srv import SetBool, Trigger
 
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+from .stm32_protocol import (
+    BAUD_RATE,
+=======
 from .esp32_protocol import (
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
     FrameParser,
-    ImuFrame, BatteryFrame, MotorRpmFrame, ArmStateFrame, ErrorFrame,
-    encode_heartbeat, encode_speed_steer, encode_arm, encode_set_mode,
-    encode_pid_update,
+    RcChannels,
+    SensorData,
+    encode_heartbeat,
+    encode_led_cmd,
+    encode_output_cmd,
 )
 
-# ── Constants ─────────────────────────────────────────────────────────────────
 
-IMU_FRAME_ID = "imu_link"
-_ARM_LABEL   = {0: "DISARMED", 1: "ARMED", 2: "TILT_FAULT"}
-
-
-def _clamp(v: float, lo: float, hi: float) -> float:
-    return max(lo, min(hi, v))
-
-
-# ── Node ──────────────────────────────────────────────────────────────────────
-
-class Esp32CmdNode(Node):
-    """Binary-framed Jetson↔ESP32-S3 BALANCE bridge node."""
+class Stm32CmdNode(Node):
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+    """Orin ↔ ESP32-S3 IO auxiliary bridge node."""
+=======
+    """Binary-framed Jetson↔ESP32-S3 bridge node."""
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 
     def __init__(self) -> None:
         super().__init__("esp32_cmd_node")
 
-        # ── Parameters ────────────────────────────────────────────────────────
-        self.declare_parameter("serial_port",      "/dev/can0")
-        self.declare_parameter("baud_rate",        460800)
+        # ── Parameters ────────────────────────────────────────────────────
+        self.declare_parameter("serial_port",      "/dev/esp32-io")
+        self.declare_parameter("baud_rate",        BAUD_RATE)
         self.declare_parameter("reconnect_delay",  2.0)
         self.declare_parameter("heartbeat_period", 0.2)
-        self.declare_parameter("watchdog_timeout", 0.5)
-        self.declare_parameter("speed_scale",      1000.0)
-        self.declare_parameter("steer_scale",      -500.0)
 
-        port                  = self.get_parameter("serial_port").value
-        baud                  = self.get_parameter("baud_rate").value
+        self._port_name       = self.get_parameter("serial_port").value
+        self._baud            = self.get_parameter("baud_rate").value
         self._reconnect_delay = self.get_parameter("reconnect_delay").value
         self._hb_period       = self.get_parameter("heartbeat_period").value
-        self._wd_timeout      = self.get_parameter("watchdog_timeout").value
-        self._speed_scale     = self.get_parameter("speed_scale").value
-        self._steer_scale     = self.get_parameter("steer_scale").value
 
-        # ── QoS ───────────────────────────────────────────────────────────────
-        sensor_qos = QoSProfile(
-            reliability=ReliabilityPolicy.BEST_EFFORT,
-            history=HistoryPolicy.KEEP_LAST, depth=10,
-        )
+        # ── QoS ───────────────────────────────────────────────────────────
         rel_qos = QoSProfile(
             reliability=ReliabilityPolicy.RELIABLE,
             history=HistoryPolicy.KEEP_LAST, depth=10,
         )
 
-        # ── Publishers ────────────────────────────────────────────────────────
-        self._imu_pub      = self.create_publisher(Imu,    "/saltybot/imu",           sensor_qos)
-        self._arm_pub      = self.create_publisher(String, "/saltybot/arm_state",      rel_qos)
-        self._error_pub    = self.create_publisher(String, "/saltybot/error",          rel_qos)
-        self._battery_pub  = self.create_publisher(String, "/saltybot/telemetry/battery",  rel_qos)
-        self._rpm_pub      = self.create_publisher(String, "/saltybot/telemetry/motor_rpm", rel_qos)
+        # ── Publishers ────────────────────────────────────────────────────
+        self._rc_pub   = self.create_publisher(String,          "/saltybot/rc_channels", rel_qos)
+        self._sens_pub = self.create_publisher(String,          "/saltybot/sensors",     rel_qos)
         self._diag_pub = self.create_publisher(DiagnosticArray, "/diagnostics",          rel_qos)
 
-        # ── Subscribers ───────────────────────────────────────────────────────
-        self._cmd_vel_sub = self.create_subscription(
-            Twist, "/cmd_vel", self._on_cmd_vel, rel_qos,
-        )
-        self._pid_sub = self.create_subscription(
-            String, "/saltybot/pid_update", self._on_pid_update, rel_qos,
-        )
+        # ── Subscriptions ─────────────────────────────────────────────────
+        self.create_subscription(String, "/saltybot/leds",    self._on_leds,    rel_qos)
+        self.create_subscription(String, "/saltybot/outputs", self._on_outputs, rel_qos)
 
-        # ── Services ──────────────────────────────────────────────────────────
-        self._arm_srv  = self.create_service(SetBool, "/saltybot/arm",      self._svc_arm)
-        self._mode_srv = self.create_service(SetBool, "/saltybot/set_mode", self._svc_set_mode)
-
-        # ── Serial state ──────────────────────────────────────────────────────
-        self._port_name = port
-        self._baud      = baud
+        # ── Serial state ──────────────────────────────────────────────────
         self._ser: serial.Serial | None = None
         self._ser_lock = threading.Lock()
         self._parser   = FrameParser()
+        self._rx_count = 0
 
-        # ── TX state ──────────────────────────────────────────────────────────
-        self._last_speed    = 0
-        self._last_steer    = 0
-        self._last_cmd_t    = time.monotonic()
-        self._watchdog_sent = False     # tracks whether we already sent zero
-
-        # ── Diagnostics state ──────────────────────────────────────────────────
-        self._last_arm_state   = -1
-        self._last_battery_mv  = 0
-        self._rx_frame_count   = 0
-
-        # ── Open serial and start timers ──────────────────────────────────────
+        # ── Open serial and start timers ──────────────────────────────────
         self._open_serial()
 
-        # Read at 200 Hz (serial RX thread is better, but timer keeps ROS2 integration clean)
         self._read_timer = self.create_timer(0.005,           self._read_cb)
-        # Heartbeat TX
         self._hb_timer   = self.create_timer(self._hb_period, self._heartbeat_cb)
-        # Watchdog check (fires at 2× watchdog_timeout for quick detection)
-        self._wd_timer   = self.create_timer(self._wd_timeout / 2, self._watchdog_cb)
-        # Periodic diagnostics
         self._diag_timer = self.create_timer(1.0,             self._publish_diagnostics)
 
         self.get_logger().info(
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+            f"stm32_cmd_node started — {self._port_name} @ {self._baud} baud"
+=======
             f"esp32_cmd_node started — {port} @ {baud} baud | "
             f"HB {int(self._hb_period * 1000)}ms | WD {int(self._wd_timeout * 1000)}ms"
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
         )
 
-    # ── Serial management ─────────────────────────────────────────────────────
+    # ── Serial management ─────────────────────────────────────────────────
 
     def _open_serial(self) -> bool:
         with self._ser_lock:
@@ -170,7 +154,7 @@ class Esp32CmdNode(Node):
                 self._ser = serial.Serial(
                     port=self._port_name,
                     baudrate=self._baud,
-                    timeout=0.005,          # non-blocking reads
+                    timeout=0.005,
                     write_timeout=0.1,
                 )
                 self._ser.reset_input_buffer()
@@ -185,17 +169,7 @@ class Esp32CmdNode(Node):
                 self._ser = None
                 return False
 
-    def _close_serial(self) -> None:
-        with self._ser_lock:
-            if self._ser and self._ser.is_open:
-                try:
-                    self._ser.close()
-                except Exception:
-                    pass
-            self._ser = None
-
     def _write(self, data: bytes) -> bool:
-        """Thread-safe serial write. Returns False if port is not open."""
         with self._ser_lock:
             if self._ser is None or not self._ser.is_open:
                 return False
@@ -207,16 +181,15 @@ class Esp32CmdNode(Node):
                 self._ser = None
                 return False
 
-    # ── RX — read callback ────────────────────────────────────────────────────
+    # ── RX ────────────────────────────────────────────────────────────────
 
     def _read_cb(self) -> None:
-        """Read bytes from serial and feed them to the frame parser."""
         raw: bytes | None = None
-        reconnect_needed  = False
+        reconnect = False
 
         with self._ser_lock:
             if self._ser is None or not self._ser.is_open:
-                reconnect_needed = True
+                reconnect = True
             else:
                 try:
                     n = self._ser.in_waiting
@@ -225,9 +198,9 @@ class Esp32CmdNode(Node):
                 except serial.SerialException as exc:
                     self.get_logger().error(f"Serial read error: {exc}")
                     self._ser = None
-                    reconnect_needed = True
+                    reconnect = True
 
-        if reconnect_needed:
+        if reconnect:
             self.get_logger().warn(
                 "Serial disconnected — will retry",
                 throttle_duration_sec=self._reconnect_delay,
@@ -240,24 +213,41 @@ class Esp32CmdNode(Node):
             return
 
         for byte in raw:
-            frame = self._parser.feed(byte)
-            if frame is not None:
-                self._rx_frame_count += 1
-                self._dispatch_frame(frame)
+            msg = self._parser.feed(byte)
+            if msg is not None:
+                self._rx_count += 1
+                self._dispatch(msg)
 
-    def _dispatch_frame(self, frame) -> None:
-        """Route a decoded frame to the appropriate publisher."""
+    def _dispatch(self, msg) -> None:
         now = self.get_clock().now().to_msg()
+        ts  = f"{now.sec}.{now.nanosec:09d}"
 
-        if isinstance(frame, ImuFrame):
-            self._publish_imu(frame, now)
+        if isinstance(msg, RcChannels):
+            out = String()
+            out.data = json.dumps({
+                "channels": msg.channels,
+                "source":   msg.source,
+                "ts":       ts,
+            })
+            self._rc_pub.publish(out)
 
-        elif isinstance(frame, BatteryFrame):
-            self._publish_battery(frame, now)
+        elif isinstance(msg, SensorData):
+            out = String()
+            out.data = json.dumps({
+                "pressure_pa":   msg.pressure_pa,
+                "temperature_c": msg.temperature_c,
+                "tof_mm":        msg.tof_mm,
+                "ts":            ts,
+            })
+            self._sens_pub.publish(out)
 
-        elif isinstance(frame, MotorRpmFrame):
-            self._publish_motor_rpm(frame, now)
+        elif isinstance(msg, tuple):
+            type_code, _ = msg
+            self.get_logger().debug(f"Unknown inter-board type 0x{type_code:02X}")
 
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+    # ── TX ────────────────────────────────────────────────────────────────
+=======
         elif isinstance(frame, ArmStateFrame):
             self._publish_arm_state(frame, now)
 
@@ -368,108 +358,85 @@ class Esp32CmdNode(Node):
                 "SPEED_STEER dropped — serial not open",
                 throttle_duration_sec=2.0,
             )
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
 
     def _heartbeat_cb(self) -> None:
-        """Send HEARTBEAT every heartbeat_period (default 200ms)."""
         self._write(encode_heartbeat())
 
-    def _watchdog_cb(self) -> None:
-        """Send zero-speed if /cmd_vel silent for watchdog_timeout seconds."""
-        if time.monotonic() - self._last_cmd_t >= self._wd_timeout:
-            if not self._watchdog_sent:
-                self.get_logger().warn(
-                    f"No /cmd_vel for {self._wd_timeout:.1f}s — sending zero-speed"
-                )
-                self._watchdog_sent = True
-            self._last_speed = 0
-            self._last_steer = 0
-            self._write(encode_speed_steer(0, 0))
-
-    def _on_pid_update(self, msg: String) -> None:
-        """Parse JSON /saltybot/pid_update and send PID_UPDATE frame."""
+    def _on_leds(self, msg: String) -> None:
+        """Parse JSON {"pattern":N,"r":R,"g":G,"b":B} and send LED_CMD."""
         try:
-            data = json.loads(msg.data)
-            kp = float(data["kp"])
-            ki = float(data["ki"])
-            kd = float(data["kd"])
-        except (ValueError, KeyError, json.JSONDecodeError) as exc:
-            self.get_logger().error(f"Bad PID update JSON: {exc}")
-            return
-        frame = encode_pid_update(kp, ki, kd)
-        if self._write(frame):
-            self.get_logger().info(f"PID update: kp={kp}, ki={ki}, kd={kd}")
-        else:
-            self.get_logger().warn("PID_UPDATE dropped — serial not open")
-
-    # ── Services ──────────────────────────────────────────────────────────────
-
-    def _svc_arm(self, request: SetBool.Request, response: SetBool.Response):
-        """SetBool(True) = arm, SetBool(False) = disarm."""
-        arm = request.data
-        frame = encode_arm(arm)
-        ok = self._write(frame)
-        response.success = ok
-        response.message = ("ARMED" if arm else "DISARMED") if ok else "serial not open"
-        self.get_logger().info(
-            f"ARM service: {'arm' if arm else 'disarm'} — {'sent' if ok else 'FAILED'}"
+            d = json.loads(msg.data)
+            frame = encode_led_cmd(
+                int(d.get("pattern", 0)),
+                int(d.get("r", 0)),
+                int(d.get("g", 0)),
+                int(d.get("b", 0)),
             )
-        return response
+        except (ValueError, KeyError, json.JSONDecodeError) as exc:
+            self.get_logger().error(f"Bad /saltybot/leds JSON: {exc}")
+            return
+        self._write(frame)
 
-    def _svc_set_mode(self, request: SetBool.Request, response: SetBool.Response):
-        """SetBool: data maps to mode byte (True=1, False=0)."""
-        mode = 1 if request.data else 0
-        frame = encode_set_mode(mode)
-        ok = self._write(frame)
-        response.success = ok
-        response.message = f"mode={mode}" if ok else "serial not open"
-        return response
+    def _on_outputs(self, msg: String) -> None:
+        """Parse JSON {"horn":bool,"buzzer":bool,"headlight":0-255,"fan":0-255}."""
+        try:
+            d = json.loads(msg.data)
+            frame = encode_output_cmd(
+                bool(d.get("horn",     False)),
+                bool(d.get("buzzer",   False)),
+                int(d.get("headlight", 0)),
+                int(d.get("fan",       0)),
+            )
+        except (ValueError, KeyError, json.JSONDecodeError) as exc:
+            self.get_logger().error(f"Bad /saltybot/outputs JSON: {exc}")
+            return
+        self._write(frame)
 
-    # ── Diagnostics ───────────────────────────────────────────────────────────
+    # ── Diagnostics ───────────────────────────────────────────────────────
 
     def _publish_diagnostics(self) -> None:
         diag = DiagnosticArray()
         diag.header.stamp = self.get_clock().now().to_msg()
-
         status = DiagnosticStatus()
+<<<<<<< HEAD:jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/stm32_cmd_node.py
+        status.name        = "saltybot/esp32_io_bridge"
+        status.hardware_id = "esp32-s3-io"
+=======
         status.name        = "saltybot/esp32_cmd_node"
-        status.hardware_id = "esp32s3_balance"
+        status.hardware_id = "esp32s322"
 
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only):jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_cmd_node.py
         port_ok = self._ser is not None and self._ser.is_open
-        if port_ok:
-            status.level   = DiagnosticStatus.OK
-            status.message = "Serial OK"
-        else:
-            status.level   = DiagnosticStatus.ERROR
-            status.message = f"Serial disconnected: {self._port_name}"
-
-        wd_age = time.monotonic() - self._last_cmd_t
+        status.level   = DiagnosticStatus.OK if port_ok else DiagnosticStatus.ERROR
+        status.message = "Serial OK" if port_ok else f"Disconnected: {self._port_name}"
         status.values  = [
             KeyValue(key="serial_port", value=self._port_name),
+            KeyValue(key="baud_rate",   value=str(self._baud)),
             KeyValue(key="port_open",   value=str(port_ok)),
-            KeyValue(key="rx_frames",      value=str(self._rx_frame_count)),
+            KeyValue(key="rx_frames",   value=str(self._rx_count)),
             KeyValue(key="rx_errors",   value=str(self._parser.frames_error)),
-            KeyValue(key="last_speed",     value=str(self._last_speed)),
-            KeyValue(key="last_steer",     value=str(self._last_steer)),
-            KeyValue(key="cmd_vel_age_s",  value=f"{wd_age:.2f}"),
-            KeyValue(key="battery_mv",     value=str(self._last_battery_mv)),
-            KeyValue(key="arm_state",      value=_ARM_LABEL.get(self._last_arm_state, "?")),
         ]
         diag.status.append(status)
         self._diag_pub.publish(diag)
 
-    # ── Lifecycle ─────────────────────────────────────────────────────────────
+    # ── Lifecycle ─────────────────────────────────────────────────────────
 
     def destroy_node(self) -> None:
-        # Send zero-speed + disarm on shutdown
-        self._write(encode_speed_steer(0, 0))
-        self._write(encode_arm(False))
-        self._close_serial()
+        self._write(encode_heartbeat(state=0))
+        with self._ser_lock:
+            if self._ser and self._ser.is_open:
+                try:
+                    self._ser.close()
+                except Exception:
+                    pass
+            self._ser = None
         super().destroy_node()
 
 
 def main(args=None) -> None:
     rclpy.init(args=args)
-    node = Esp32CmdNode()
+    node = Stm32CmdNode()
     try:
         rclpy.spin(node)
     except KeyboardInterrupt:

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/esp32_protocol.py

@@ -1,7 +1,7 @@
-"""esp32_protocol.py — Binary frame codec for Jetson↔ESP32-S3 BALANCE communication.
+"""esp32_protocol.py — Binary frame codec for Jetson↔ESP32-S3 communication.
 
 Issue #119: defines the binary serial protocol between the Jetson Orin Nano Super and the
-ESP32-S3 BALANCE board over inter-board UART @ 460800 baud.
+ESP32-S3 ESP32-S3 BALANCE over USB CDC @ 921600 baud.
 
 Frame layout (all multi-byte fields are big-endian):
   ┌──────┬──────┬──────┬──────────────────┬───────────┬──────┐
@@ -12,14 +12,14 @@ Frame layout (all multi-byte fields are big-endian):
 CRC16 covers: TYPE + LEN + PAYLOAD (not STX, ETX, or CRC bytes themselves).
 CRC algorithm: CCITT-16, polynomial=0x1021, init=0xFFFF, no final XOR.
 
-Command types (Jetson → ESP32-S3 BALANCE):
+Command types (Jetson → ESP32-S3):
   0x01  HEARTBEAT   — no payload              (len=0)
   0x02  SPEED_STEER — int16 speed + int16 steer (len=4)  range: -1000..+1000
   0x03  ARM         — uint8 (0=disarm, 1=arm)  (len=1)
   0x04  SET_MODE    — uint8 mode               (len=1)
   0x05  PID_UPDATE  — float32 kp + ki + kd     (len=12)
 
-Telemetry types (ESP32-S3 BALANCE → Jetson):
+Telemetry types (ESP32-S3 → Jetson):
   0x10  IMU         — int16×6: pitch,roll,yaw (×100 deg), ax,ay,az (×100 m/s²) (len=12)
   0x11  BATTERY     — uint16 voltage_mv + int16 current_ma + uint8 soc_pct (len=5)
   0x12  MOTOR_RPM   — int16 left_rpm + int16 right_rpm     (len=4)
@@ -27,11 +27,11 @@ Telemetry types (ESP32-S3 BALANCE → Jetson):
   0x14  ERROR       — uint8 error_code + uint8 subcode      (len=2)
 
 Usage:
-  # Encoding (Jetson → ESP32-S3 BALANCE)
+  # Encoding (Jetson → ESP32-S3)
   frame = encode_speed_steer(300, -150)
   ser.write(frame)
 
-  # Decoding (ESP32-S3 BALANCE → Jetson), one byte at a time
+  # Decoding (ESP32-S3 → Jetson), one byte at a time
   parser = FrameParser()
   for byte in incoming_bytes:
       result = parser.feed(byte)
@@ -87,7 +87,7 @@ class ImuFrame:
 class BatteryFrame:
     voltage_mv:  int      # millivolts (e.g. 11100 = 11.1 V)
     current_ma:  int      # milliamps (negative = charging)
-    soc_pct:     int      # state of charge 0–100 (from ESP32-S3 BALANCE fuel gauge or lookup)
+    soc_pct:     int      # state of charge 0–100 (from ESP32-S3 fuel gauge or lookup)
 
 
 @dataclass
@@ -183,7 +183,7 @@ class ParseError(Exception):
 
 
 class FrameParser:
-    """Byte-by-byte streaming parser for ESP32-S3 BALANCE telemetry frames.
+    """Byte-by-byte streaming parser for ESP32-S3 telemetry frames.
 
     Feed individual bytes via feed(); returns a decoded TelemetryFrame (or raw
     bytes tuple) when a complete valid frame is received.

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/saltybot_can_node.py

@@ -322,7 +322,11 @@ class SaltybotCanNode(Node):
         diag.header.stamp = stamp
         st = DiagnosticStatus()
         st.name        = "saltybot/balance_controller"
-        st.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        st.hardware_id = "esp32"
+=======
+        st.hardware_id = "esp32s322"
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         st.message     = state_label
         st.level       = (DiagnosticStatus.OK    if state == 1 else
                           DiagnosticStatus.WARN   if state == 0 else

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/saltybot_cmd_node.py

@@ -1,20 +1,38 @@
 """
-saltybot_cmd_node — full bidirectional STM32↔Jetson bridge
+<<<<<<< HEAD
+saltybot_cmd_node — full bidirectional ESP32 BALANCE↔Jetson bridge
+=======
+saltybot_cmd_node — full bidirectional ESP32-S3↔Jetson bridge
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 Combines telemetry RX (from serial_bridge_node) with drive command TX.
 
 Owns /dev/ttyACM0 exclusively — do NOT run alongside serial_bridge_node.
 
-RX path (50Hz from STM32):
+<<<<<<< HEAD
+RX path (50Hz from ESP32 BALANCE):
   JSON telemetry → /saltybot/imu, /saltybot/balance_state, /diagnostics
 
 TX path:
-  /cmd_vel (geometry_msgs/Twist) → C<speed>,<steer>\\n  → STM32
-  Heartbeat timer (200ms)        → H\\n                 → STM32
+  /cmd_vel (geometry_msgs/Twist) → C<speed>,<steer>\\n  → ESP32 BALANCE
+  Heartbeat timer (200ms)        → H\\n                 → ESP32 BALANCE
 
 Protocol:
-  H\\n              — heartbeat. STM32 reverts steer to 0 if gap > 500ms.
+  H\\n              — heartbeat. ESP32 BALANCE reverts steer to 0 if gap > 500ms.
   C<spd>,<str>\\n   — drive command. speed/steer: -1000..+1000 integers.
-                      C command also refreshes STM32 heartbeat timer.
+                      C command also refreshes ESP32 BALANCE heartbeat timer.
+=======
+RX path (50Hz from ESP32-S3):
+  JSON telemetry → /saltybot/imu, /saltybot/balance_state, /diagnostics
+
+TX path:
+  /cmd_vel (geometry_msgs/Twist) → C<speed>,<steer>\\n  → ESP32-S3
+  Heartbeat timer (200ms)        → H\\n                 → ESP32-S3
+
+Protocol:
+  H\\n              — heartbeat. ESP32-S3 reverts steer to 0 if gap > 500ms.
+  C<spd>,<str>\\n   — drive command. speed/steer: -1000..+1000 integers.
+                      C command also refreshes ESP32-S3 heartbeat timer.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 Twist mapping (configurable via ROS2 params):
   speed = clamp(linear.x  * speed_scale, -1000, 1000)
@@ -100,7 +118,11 @@ class SaltybotCmdNode(Node):
         self._open_serial()
 
         # ── Timers ────────────────────────────────────────────────────────────
-        # Telemetry read at 100Hz (STM32 sends at 50Hz)
+<<<<<<< HEAD
+        # Telemetry read at 100Hz (ESP32 BALANCE sends at 50Hz)
+=======
+        # Telemetry read at 100Hz (ESP32-S3 sends at 50Hz)
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         self._read_timer = self.create_timer(0.01, self._read_cb)
         # Heartbeat TX at configured period (default 200ms)
         self._hb_timer   = self.create_timer(self._hb_period, self._heartbeat_cb)
@@ -266,7 +288,11 @@ class SaltybotCmdNode(Node):
         diag.header.stamp = stamp
         status = DiagnosticStatus()
         status.name = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
+=======
+        status.hardware_id = "esp32s322"
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         status.message = state_label
         if state == 1:
             status.level = DiagnosticStatus.OK
@@ -294,11 +320,19 @@ class SaltybotCmdNode(Node):
         status = DiagnosticStatus()
         status.level = DiagnosticStatus.ERROR
         status.name = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
         status.message = f"IMU fault errno={errno}"
         diag.status.append(status)
         self._diag_pub.publish(diag)
-        self.get_logger().error(f"STM32 IMU fault: errno={errno}")
+        self.get_logger().error(f"ESP32 BALANCE IMU fault: errno={errno}")
+=======
+        status.hardware_id = "esp32s322"
+        status.message = f"IMU fault errno={errno}"
+        diag.status.append(status)
+        self._diag_pub.publish(diag)
+        self.get_logger().error(f"ESP32-S3 IMU fault: errno={errno}")
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
     # ── TX — command send ─────────────────────────────────────────────────────
 
@@ -316,7 +350,11 @@ class SaltybotCmdNode(Node):
             )
 
     def _heartbeat_cb(self):
-        """Send H\\n heartbeat. STM32 reverts steer to 0 if gap > 500ms."""
+<<<<<<< HEAD
+        """Send H\\n heartbeat. ESP32 BALANCE reverts steer to 0 if gap > 500ms."""
+=======
+        """Send H\\n heartbeat. ESP32-S3 reverts steer to 0 if gap > 500ms."""
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         self._write(b"H\n")
 
     # ── Lifecycle ─────────────────────────────────────────────────────────────

jetson/ros2_ws/src/saltybot_bridge/saltybot_bridge/serial_bridge_node.py

@@ -1,6 +1,10 @@
 """
 saltybot_bridge — serial_bridge_node
-ESP32-S3 BALANCE → ROS2 topic publisher (inter-board UART)
+<<<<<<< HEAD
+ESP32 USB CDC → ROS2 topic publisher
+=======
+ESP32-S3 USB CDC → ROS2 topic publisher
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
 Telemetry frame (50 Hz, newline-delimited JSON):
   {"p":<pitch×10>,"r":<roll×10>,"e":<err×10>,"ig":<integral×10>,
@@ -29,7 +33,11 @@ from sensor_msgs.msg import Imu
 from std_msgs.msg import String
 from diagnostic_msgs.msg import DiagnosticArray, DiagnosticStatus, KeyValue
 
-# Balance state labels matching STM32 balance_state_t enum
+<<<<<<< HEAD
+# Balance state labels matching ESP32 BALANCE balance_state_t enum
+=======
+# Balance state labels matching ESP32-S3 balance_state_t enum
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 _STATE_LABEL = {0: "DISARMED", 1: "ARMED", 2: "TILT_FAULT"}
 
 # Sensor frame_id published in Imu header
@@ -38,7 +46,7 @@ IMU_FRAME_ID = "imu_link"
 
 class SerialBridgeNode(Node):
     def __init__(self):
-        super().__init__("stm32_serial_bridge")
+        super().__init__("esp32_serial_bridge")
 
         # ── Parameters ────────────────────────────────────────────────────────
         self.declare_parameter("serial_port", "/dev/ttyACM0")
@@ -83,7 +91,11 @@ class SerialBridgeNode(Node):
 
         # ── Open serial and start read timer ──────────────────────────────────
         self._open_serial()
-        # Poll at 100 Hz — STM32 sends at 50 Hz, so we never miss a frame
+<<<<<<< HEAD
+        # Poll at 100 Hz — ESP32 BALANCE sends at 50 Hz, so we never miss a frame
+=======
+        # Poll at 100 Hz — ESP32-S3 sends at 50 Hz, so we never miss a frame
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         self._timer = self.create_timer(0.01, self._read_cb)
 
         self.get_logger().info(
@@ -117,7 +129,11 @@ class SerialBridgeNode(Node):
 
     def write_serial(self, data: bytes) -> bool:
         """
-        Send raw bytes to STM32 over the open serial port.
+<<<<<<< HEAD
+        Send raw bytes to ESP32 BALANCE over the open serial port.
+=======
+        Send raw bytes to ESP32-S3 over the open serial port.
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         Returns False if port is not open (caller should handle gracefully).
         Note: for bidirectional use prefer saltybot_cmd_node which owns TX natively.
         """
@@ -206,7 +222,11 @@ class SerialBridgeNode(Node):
         """
         Publish sensor_msgs/Imu.
 
-        The STM32 IMU gives Euler angles (pitch/roll from accelerometer+gyro
+<<<<<<< HEAD
+        The ESP32 BALANCE IMU gives Euler angles (pitch/roll from accelerometer+gyro
+=======
+        The ESP32-S3 IMU gives Euler angles (pitch/roll from accelerometer+gyro
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         fusion, yaw from gyro integration). We publish them as angular_velocity
         for immediate use by slam_toolbox / robot_localization.
 
@@ -264,7 +284,11 @@ class SerialBridgeNode(Node):
         diag.header.stamp = stamp
         status = DiagnosticStatus()
         status.name = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
+=======
+        status.hardware_id = "esp32s322"
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
         status.message = state_label
 
         if state == 1:   # ARMED
@@ -293,11 +317,19 @@ class SerialBridgeNode(Node):
         status = DiagnosticStatus()
         status.level = DiagnosticStatus.ERROR
         status.name = "saltybot/balance_controller"
-        status.hardware_id = "esp32s3_balance"
+<<<<<<< HEAD
+        status.hardware_id = "esp32"
         status.message = f"IMU fault errno={errno}"
         diag.status.append(status)
         self._diag_pub.publish(diag)
-        self.get_logger().error(f"STM32 reported IMU fault: errno={errno}")
+        self.get_logger().error(f"ESP32 BALANCE reported IMU fault: errno={errno}")
+=======
+        status.hardware_id = "esp32s322"
+        status.message = f"IMU fault errno={errno}"
+        diag.status.append(status)
+        self._diag_pub.publish(diag)
+        self.get_logger().error(f"ESP32-S3 reported IMU fault: errno={errno}")
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 
     def destroy_node(self):
         self._close_serial()

jetson/ros2_ws/src/saltybot_bringup/config/rosbridge_params.yaml

@@ -53,7 +53,14 @@ rosbridge_websocket:
        "/vesc/left/state",
        "/vesc/right/state",
        "/tf",
-       "/tf_static"]
+       "/tf_static",
+       "/saltybot/phone/gps",
+       "/saltybot/phone/imu",
+       "/saltybot/phone/battery",
+       "/saltybot/phone/bridge/status",
+       "/gps/fix",
+       "/gps/vel",
+       "/saltybot/ios/gps"]
 
     services_glob: "[]"       # no service calls via WebSocket
     params_glob:   "[]"       # no parameter access via WebSocket
@@ -67,7 +74,7 @@ rosbridge_websocket:
 
     # Delay between consecutive outgoing messages (ms). 0 = unlimited.
     # Set > 0 (e.g. 10) if browser JS event loop is overwhelmed.
-    delay_between_messages: 0
+    delay_between_messages: 0.0
 
     # ── Logging ───────────────────────────────────────────────────────────────
     # Set to true to log every publish/subscribe call (verbose, dev only).

jetson/ros2_ws/src/saltybot_bringup/launch/full_stack.launch.py

@@ -39,11 +39,7 @@ Modes
     ─ UWB driver (2-anchor DW3000, publishes /uwb/target)
     ─ YOLOv8n person detection (TensorRT)
     ─ Person follower with UWB+camera fusion
-<<<<<<< HEAD
-    ─ cmd_vel bridge → ESP32 BALANCE (deadman + ramp + AUTONOMOUS gate)
-=======
     ─ cmd_vel bridge → ESP32-S3 (deadman + ramp + AUTONOMOUS gate)
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
     ─ rosbridge WebSocket (port 9090)
 
   outdoor
@@ -61,13 +57,8 @@ Modes
 Launch sequence (wall-clock delays — conservative for cold start)
 ─────────────────────────────────────────────────────────────────
    t= 0s  robot_description   (URDF + TF tree)
-<<<<<<< HEAD
-   t= 0s  ESP32 bridge        (serial port owner — must be first)
-   t= 2s  cmd_vel bridge      (consumes /cmd_vel, needs ESP32 bridge up)
-=======
    t= 0s  ESP32-S3 bridge        (serial port owner — must be first)
    t= 2s  cmd_vel bridge      (consumes /cmd_vel, needs ESP32-S3 bridge up)
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
    t= 2s  sensors             (RPLIDAR + RealSense)
    t= 4s  UWB driver          (independent serial device)
    t= 4s  CSI cameras         (optional, independent)
@@ -80,17 +71,10 @@ Launch sequence (wall-clock delays — conservative for cold start)
 
 Safety wiring
 ─────────────
-<<<<<<< HEAD
-  • ESP32 bridge must be up before cmd_vel bridge sends any command.
-  • cmd_vel bridge has 500ms deadman: stops robot if /cmd_vel goes silent.
-  • ESP32 BALANCE AUTONOMOUS mode gate (md=2) in cmd_vel bridge — robot stays still
-    until ESP32 BALANCE firmware is in AUTONOMOUS mode regardless of /cmd_vel.
-=======
   • ESP32-S3 bridge must be up before cmd_vel bridge sends any command.
   • cmd_vel bridge has 500ms deadman: stops robot if /cmd_vel goes silent.
   • ESP32-S3 AUTONOMOUS mode gate (md=2) in cmd_vel bridge — robot stays still
     until ESP32-S3 firmware is in AUTONOMOUS mode regardless of /cmd_vel.
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   • follow_enabled:=false disables person follower without stopping the node.
   • To e-stop at runtime: ros2 topic pub /saltybot/estop std_msgs/Bool '{data: true}'
 
@@ -107,11 +91,7 @@ Topics published by this stack
   /person/target                   PoseStamped    (camera position, base_link)
   /person/detections               Detection2DArray
   /cmd_vel                         Twist          (from follower or Nav2)
-<<<<<<< HEAD
-  /saltybot/cmd                    String         (to ESP32 BALANCE)
-=======
   /saltybot/cmd                    String         (to ESP32-S3)
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   /saltybot/imu                    Imu
   /saltybot/balance_state          String
 """
@@ -229,11 +209,7 @@ def generate_launch_description():
     enable_bridge_arg = DeclareLaunchArgument(
         "enable_bridge",
         default_value="true",
-<<<<<<< HEAD
-        description="Launch ESP32 serial bridge + cmd_vel bridge (disable for sim/rosbag)",
-=======
         description="Launch ESP32-S3 serial bridge + cmd_vel bridge (disable for sim/rosbag)",
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
     )
 
     enable_rosbridge_arg = DeclareLaunchArgument(
@@ -242,7 +218,7 @@ def generate_launch_description():
         description="Launch rosbridge WebSocket server (port 9090)",
     )
 
-enable_mission_logging_arg = DeclareLaunchArgument(
+    enable_mission_logging_arg = DeclareLaunchArgument(
         "enable_mission_logging",
         default_value="true",
         description="Launch ROS2 bag recorder for mission logging (Issue #488)",
@@ -294,11 +270,7 @@ enable_mission_logging_arg = DeclareLaunchArgument(
     esp32_port_arg = DeclareLaunchArgument(
         "esp32_port",
         default_value="/dev/esp32-bridge",
-<<<<<<< HEAD
-        description="ESP32 USB CDC serial port",
-=======
         description="ESP32-S3 USB CDC serial port",
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
     )
 
     # ── Shared substitution handles ───────────────────────────────────────────
@@ -318,11 +290,7 @@ enable_mission_logging_arg = DeclareLaunchArgument(
         launch_arguments={"use_sim_time": use_sim_time}.items(),
     )
 
-<<<<<<< HEAD
-    # ── t=0s  ESP32 bidirectional serial bridge ────────────────────────────────
-=======
-    # ── t=0s  ESP32-S3 bidirectional serial bridge ────────────────────────────────
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
+    # ── t=0s  ESP32-S3 bidirectional serial bridge ───────────────────────────────
     esp32_bridge = GroupAction(
         condition=IfCondition(LaunchConfiguration("enable_bridge")),
         actions=[
@@ -352,11 +320,7 @@ enable_mission_logging_arg = DeclareLaunchArgument(
         ],
     )
 
-<<<<<<< HEAD
-    # ── t=2s  cmd_vel safety bridge (depends on ESP32 bridge) ────────────────
-=======
     # ── t=2s  cmd_vel safety bridge (depends on ESP32-S3 bridge) ────────────────
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
     cmd_vel_bridge = TimerAction(
         period=2.0,
         actions=[

jetson/ros2_ws/src/saltybot_bringup/systemd/can-bringup.service

@@ -1,5 +1,5 @@
 [Unit]
-Description=CANable 2.0 CAN bus bringup (can0, 500 kbps)
+Description=CANable 2.0 CAN bus bringup (can0, 1 Mbps DroneCAN — Here4 GPS)
 Documentation=https://gitea.vayrette.com/seb/saltylab-firmware/issues/643
 # Wait until the gs_usb net device appears; udev fires After=sys-subsystem-net-devices-can0.device
 After=network.target sys-subsystem-net-devices-can0.device
@@ -10,7 +10,7 @@ BindsTo=sys-subsystem-net-devices-can0.device
 Type=oneshot
 RemainAfterExit=yes
 
-ExecStart=/usr/sbin/ip link set can0 up type can bitrate 500000
+ExecStart=/usr/sbin/ip link set can0 up type can bitrate 1000000
 ExecStop=/usr/sbin/ip link set can0 down
 
 StandardOutput=journal

jetson/ros2_ws/src/saltybot_bringup/test/README_INTEGRATION_TESTS.md

@@ -61,7 +61,11 @@ kill %1
 
 ### Core System Components
 - Robot Description (URDF/TF tree)
-- ESP32-S3 CAN Bridge
+<<<<<<< HEAD
+- ESP32 Serial Bridge
+=======
+- ESP32-S3 Serial Bridge
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 - cmd_vel Bridge  
 - Rosbridge WebSocket
 
@@ -125,11 +129,15 @@ free -h
 
 ### cmd_vel bridge not responding
 ```bash
-# Verify CAN bridge is running first
+<<<<<<< HEAD
+# Verify ESP32 bridge is running first
+=======
+# Verify ESP32-S3 bridge is running first
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 ros2 node list | grep bridge
 
-# Check CAN interface
-ip link show can0
+# Check serial port
+ls -l /dev/esp32-bridge
 ```
 
 ## Performance Baseline

jetson/ros2_ws/src/saltybot_bringup/udev/70-canable.rules

@@ -2,6 +2,10 @@
 # Exposes the adapter as can0 via the SocketCAN subsystem.
 # Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/643
 #
+# Bitrate is set by can-bringup.service (1 Mbps DroneCAN for Here4 GPS, bd-p47c).
+# This rule only assigns the interface name and tags it for systemd; it does NOT
+# bring up the interface — that is handled by can-bringup.service.
+#
 # Install:
 #   sudo cp 70-canable.rules /etc/udev/rules.d/
 #   sudo udevadm control --reload && sudo udevadm trigger
@@ -16,4 +20,4 @@
 SUBSYSTEM=="net", ACTION=="add", \
     ATTRS{idVendor}=="1d50", ATTRS{idProduct}=="606f", \
     NAME="can0", \
-    RUN+="/sbin/ip link set can0 up type can bitrate 500000"
+    TAG+="systemd"

jetson/ros2_ws/src/saltybot_bringup/udev/80-esp32.rules

@@ -0,0 +1,31 @@
+# ESP32-S3 USB serial devices (bd-wim1)
+#
+# ESP32-S3 BALANCE (Waveshare LCD 1.28) — USB CDC via CH343 USB-UART chip
+#   Appears as /dev/ttyACM0, symlinked to /dev/esp32-balance
+#   idVendor  = 1a86  (QinHeng Electronics / WCH)
+#   idProduct = 55d4  (CH343 USB-UART)
+#
+# ESP32-S3 IO (bare board JTAG USB) — native USB CDC
+#   Appears as /dev/ttyACM1, symlinked to /dev/esp32-io
+#   idVendor  = 303a  (Espressif)
+#   idProduct = 1001  (ESP32-S3 USB CDC)
+#
+# Install:
+#   sudo cp 80-esp32.rules /etc/udev/rules.d/
+#   sudo udevadm control --reload && sudo udevadm trigger
+#
+# Verify:
+#   ls -la /dev/esp32-*
+#   python3 -c "import serial; s=serial.Serial('/dev/esp32-balance', 460800); s.close(); print('OK')"
+
+# ESP32-S3 BALANCE — CH343 USB-UART (bd-wim1 UART serial bridge)
+SUBSYSTEM=="tty", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="55d4", \
+    SYMLINK+="esp32-balance", \
+    TAG+="systemd", \
+    MODE="0660", GROUP="dialout"
+
+# ESP32-S3 IO — Espressif native USB CDC
+SUBSYSTEM=="tty", ATTRS{idVendor}=="303a", ATTRS{idProduct}=="1001", \
+    SYMLINK+="esp32-io", \
+    TAG+="systemd", \
+    MODE="0660", GROUP="dialout"

jetson/ros2_ws/src/saltybot_can_bridge/saltybot_can_bridge/balance_protocol.py

@@ -6,13 +6,13 @@ and VESC telemetry.
 CAN message layout
 ------------------
 Command frames  (Orin → ESP32-S3 BALANCE / VESC):
-  BALANCE_CMD_VELOCITY  0x100  8 bytes  left_speed (f32, m/s) | right_speed (f32, m/s)
-  BALANCE_CMD_MODE      0x101  1 byte   mode (0=idle, 1=drive, 2=estop)
-  BALANCE_CMD_ESTOP     0x102  1 byte   0x01 = stop
+  MAMBA_CMD_VELOCITY  0x100  8 bytes  left_speed (f32, m/s) | right_speed (f32, m/s)
+  MAMBA_CMD_MODE      0x101  1 byte   mode (0=idle, 1=drive, 2=estop)
+  MAMBA_CMD_ESTOP     0x102  1 byte   0x01 = stop
 
 Telemetry frames (ESP32-S3 BALANCE → Orin):
-  BALANCE_TELEM_IMU     0x200  24 bytes accel_x, accel_y, accel_z, gyro_x, gyro_y, gyro_z (f32 each)
-  BALANCE_TELEM_BATTERY 0x201   8 bytes voltage (f32, V) | current (f32, A)
+  MAMBA_TELEM_IMU     0x200  24 bytes accel_x, accel_y, accel_z, gyro_x, gyro_y, gyro_z (f32 each)
+  MAMBA_TELEM_BATTERY 0x201   8 bytes voltage (f32, V) | current (f32, A)
 
 VESC telemetry frame (VESC → Orin):
   VESC_TELEM_STATE    0x300  16 bytes erpm (f32) | duty (f32) | voltage (f32) | current (f32)
@@ -30,12 +30,12 @@ from typing import Tuple
 # CAN message IDs
 # ---------------------------------------------------------------------------
 
-BALANCE_CMD_VELOCITY: int = 0x100
-BALANCE_CMD_MODE: int = 0x101
-BALANCE_CMD_ESTOP: int = 0x102
+MAMBA_CMD_VELOCITY: int = 0x100
+MAMBA_CMD_MODE: int = 0x101
+MAMBA_CMD_ESTOP: int = 0x102
 
-BALANCE_TELEM_IMU: int = 0x200
-BALANCE_TELEM_BATTERY: int = 0x201
+MAMBA_TELEM_IMU: int = 0x200
+MAMBA_TELEM_BATTERY: int = 0x201
 
 VESC_TELEM_STATE: int = 0x300
 ORIN_CAN_ID_PID_SET: int = 0x305
@@ -56,7 +56,7 @@ MODE_ESTOP: int = 2
 
 @dataclass
 class ImuTelemetry:
-    """Decoded IMU telemetry from ESP32-S3 BALANCE (BALANCE_TELEM_IMU)."""
+    """Decoded IMU telemetry from ESP32-S3 BALANCE (MAMBA_TELEM_IMU)."""
 
     accel_x: float = 0.0  # m/s²
     accel_y: float = 0.0
@@ -68,7 +68,7 @@ class ImuTelemetry:
 
 @dataclass
 class BatteryTelemetry:
-    """Decoded battery telemetry from ESP32-S3 BALANCE (BALANCE_TELEM_BATTERY)."""
+    """Decoded battery telemetry from ESP32-S3 BALANCE (MAMBA_TELEM_BATTERY)."""
 
     voltage: float = 0.0   # V
     current: float = 0.0   # A
@@ -106,7 +106,7 @@ _FMT_VESC = ">ffff"    # 4 × float32
 
 def encode_velocity_cmd(left_mps: float, right_mps: float) -> bytes:
     """
-    Encode a BALANCE_CMD_VELOCITY payload.
+    Encode a MAMBA_CMD_VELOCITY payload.
 
     Parameters
     ----------
@@ -122,7 +122,7 @@ def encode_velocity_cmd(left_mps: float, right_mps: float) -> bytes:
 
 def encode_mode_cmd(mode: int) -> bytes:
     """
-    Encode a BALANCE_CMD_MODE payload.
+    Encode a MAMBA_CMD_MODE payload.
 
     Parameters
     ----------
@@ -139,7 +139,7 @@ def encode_mode_cmd(mode: int) -> bytes:
 
 def encode_estop_cmd(stop: bool = True) -> bytes:
     """
-    Encode a BALANCE_CMD_ESTOP payload.
+    Encode a MAMBA_CMD_ESTOP payload.
 
     Parameters
     ----------
@@ -165,7 +165,7 @@ def encode_pid_set_cmd(kp: float, ki: float, kd: float) -> bytes:
 
 def decode_imu_telem(data: bytes) -> ImuTelemetry:
     """
-    Decode a BALANCE_TELEM_IMU payload.
+    Decode a MAMBA_TELEM_IMU payload.
 
     Parameters
     ----------
@@ -188,7 +188,7 @@ def decode_imu_telem(data: bytes) -> ImuTelemetry:
 
 def decode_battery_telem(data: bytes) -> BatteryTelemetry:
     """
-    Decode a BALANCE_TELEM_BATTERY payload.
+    Decode a MAMBA_TELEM_BATTERY payload.
 
     Parameters
     ----------

jetson/ros2_ws/src/saltybot_can_bridge/saltybot_can_bridge/can_bridge_node.py

@@ -1,10 +1,9 @@
 #!/usr/bin/env python3
 """
-can_bridge_node.py — ROS2 node bridging the SaltyBot Orin to the ESP32-S3 BALANCE
+can_bridge_node.py — ROS2 node bridging the SaltyBot Orin to the ESP32-S3 BALANCE motor
 controller and VESC motor controllers over CAN bus.
 
-The node opens the SocketCAN interface (slcan0 by default), spawns a background
-reader thread to process incoming telemetry, and exposes the following interface:
+Spec: docs/SAUL-TEE-SYSTEM-REFERENCE.md §6 (2026-04-04)
 
 Subscriptions
 -------------
@@ -19,9 +18,15 @@ Publications
   /can/vesc/right/state   std_msgs/Float32MultiArray   Right VESC state
   /can/connection_status  std_msgs/String              "connected" | "disconnected"
 
-Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/674
+Parameters
+----------
+  can_interface     str    CAN socket name (default: slcan0)
+  speed_scale       float  /cmd_vel linear.x (m/s) → motor units  (default: 1000.0)
+  steer_scale       float  /cmd_vel angular.z (rad/s) → motor units (default: -500.0)
+  command_timeout_s float  watchdog zero-vel threshold (default: 0.5)
 """
 
+import json
 import threading
 import time
 from typing import Optional
@@ -30,36 +35,32 @@ import can
 import rclpy
 from geometry_msgs.msg import Twist
 from rclpy.node import Node
-from rcl_interfaces.msg import SetParametersResult
-from sensor_msgs.msg import BatteryState, Imu
+from sensor_msgs.msg import BatteryState
 from std_msgs.msg import Bool, Float32MultiArray, String
 
 from saltybot_can_bridge.balance_protocol import (
-    BALANCE_CMD_ESTOP,
-    BALANCE_CMD_MODE,
-    BALANCE_CMD_VELOCITY,
-    BALANCE_TELEM_BATTERY,
-    BALANCE_TELEM_IMU,
+    MAMBA_CMD_ESTOP,
+    MAMBA_CMD_MODE,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_TELEM_BATTERY,
+    MAMBA_TELEM_IMU,
     VESC_TELEM_STATE,
     ORIN_CAN_ID_FC_PID_ACK,
     ORIN_CAN_ID_PID_SET,
     MODE_DRIVE,
-    MODE_ESTOP,
     MODE_IDLE,
+    encode_drive_cmd,
+    encode_arm_cmd,
     encode_estop_cmd,
-    encode_mode_cmd,
-    encode_velocity_cmd,
-    encode_pid_set_cmd,
-    decode_battery_telem,
-    decode_imu_telem,
-    decode_pid_ack,
-    decode_vesc_state,
+    decode_attitude,
+    decode_battery,
+    decode_vesc_status1,
 )
 
 # Reconnect attempt interval when CAN bus is lost
 _RECONNECT_INTERVAL_S: float = 5.0
 
-# Watchdog timer tick rate (Hz)
+# Watchdog tick rate (Hz); sends zero DRIVE when /cmd_vel is silent
 _WATCHDOG_HZ: float = 10.0
 
 
@@ -70,47 +71,38 @@ class CanBridgeNode(Node):
         super().__init__("can_bridge_node")
 
         # ── Parameters ────────────────────────────────────────────────────
-        self.declare_parameter("can_interface", "can0")
-        self.declare_parameter("left_vesc_can_id", 68)
-        self.declare_parameter("right_vesc_can_id", 56)
-        self.declare_parameter("balance_can_id", 1)
+        self.declare_parameter("can_interface",     "slcan0")
+        self.declare_parameter("left_vesc_can_id",  VESC_LEFT_ID)
+        self.declare_parameter("right_vesc_can_id", VESC_RIGHT_ID)
+        self.declare_parameter("speed_scale",       1000.0)
+        self.declare_parameter("steer_scale",       -500.0)
         self.declare_parameter("command_timeout_s", 0.5)
-        self.declare_parameter("pid/kp", 0.0)
-        self.declare_parameter("pid/ki", 0.0)
-        self.declare_parameter("pid/kd", 0.0)
 
-        self._iface: str = self.get_parameter("can_interface").value
-        self._left_vesc_id: int = self.get_parameter("left_vesc_can_id").value
-        self._right_vesc_id: int = self.get_parameter("right_vesc_can_id").value
-        self._balance_id: int = self.get_parameter("balance_can_id").value
-        self._cmd_timeout: float = self.get_parameter("command_timeout_s").value
-        self._pid_kp: float = self.get_parameter("pid/kp").value
-        self._pid_ki: float = self.get_parameter("pid/ki").value
-        self._pid_kd: float = self.get_parameter("pid/kd").value
+        self._iface         = self.get_parameter("can_interface").value
+        self._left_vesc_id  = self.get_parameter("left_vesc_can_id").value
+        self._right_vesc_id = self.get_parameter("right_vesc_can_id").value
+        self._speed_scale   = self.get_parameter("speed_scale").value
+        self._steer_scale   = self.get_parameter("steer_scale").value
+        self._cmd_timeout   = self.get_parameter("command_timeout_s").value
 
         # ── State ─────────────────────────────────────────────────────────
         self._bus: Optional[can.BusABC] = None
         self._connected: bool = False
         self._last_cmd_time: float = time.monotonic()
-        self._lock = threading.Lock()  # protects _bus / _connected
+        self._lock = threading.Lock()
 
         # ── Publishers ────────────────────────────────────────────────────
-        self._pub_imu = self.create_publisher(Imu, "/can/imu", 10)
+        self._pub_attitude  = self.create_publisher(String,           "/saltybot/attitude",      10)
+        self._pub_balance   = self.create_publisher(String,           "/saltybot/balance_state", 10)
         self._pub_battery   = self.create_publisher(BatteryState,     "/can/battery",            10)
-        self._pub_vesc_left = self.create_publisher(
-            Float32MultiArray, "/can/vesc/left/state", 10
-        )
-        self._pub_vesc_right = self.create_publisher(
-            Float32MultiArray, "/can/vesc/right/state", 10
-        )
-        self._pub_status = self.create_publisher(
-            String, "/can/connection_status", 10
-        )
+        self._pub_vesc_left = self.create_publisher(Float32MultiArray,"/can/vesc/left/state",    10)
+        self._pub_vesc_right= self.create_publisher(Float32MultiArray,"/can/vesc/right/state",   10)
+        self._pub_status    = self.create_publisher(String,           "/can/connection_status",  10)
 
         # ── Subscriptions ─────────────────────────────────────────────────
         self.create_subscription(Twist, "/cmd_vel",       self._cmd_vel_cb, 10)
         self.create_subscription(Bool,  "/estop",         self._estop_cb,   10)
-        self.add_on_set_parameters_callback(self._on_set_parameters)
+        self.create_subscription(Bool,  "/saltybot/arm",  self._arm_cb,     10)
 
         # ── Timers ────────────────────────────────────────────────────────
         self.create_timer(1.0 / _WATCHDOG_HZ,  self._watchdog_cb)
@@ -128,46 +120,17 @@ class CanBridgeNode(Node):
         self.get_logger().info(
             f"can_bridge_node ready — iface={self._iface} "
             f"left_vesc={self._left_vesc_id} right_vesc={self._right_vesc_id} "
-            f"balance={self._balance_id}"
+            f"speed_scale={self._speed_scale} steer_scale={self._steer_scale}"
         )
 
-    # -- PID parameter callback (Issue #693) --
-
-    def _on_set_parameters(self, params) -> SetParametersResult:
-        """Send new PID gains over CAN when pid/* params change."""
-        for p in params:
-            if p.name == "pid/kp":
-                self._pid_kp = float(p.value)
-            elif p.name == "pid/ki":
-                self._pid_ki = float(p.value)
-            elif p.name == "pid/kd":
-                self._pid_kd = float(p.value)
-            else:
-                continue
-            try:
-                payload = encode_pid_set_cmd(self._pid_kp, self._pid_ki, self._pid_kd)
-                self._send_can(ORIN_CAN_ID_PID_SET, payload, "pid_set")
-                self.get_logger().info(
-                    f"PID gains sent: Kp={self._pid_kp:.2f} "
-                    f"Ki={self._pid_ki:.2f} Kd={self._pid_kd:.2f}"
-                )
-            except ValueError as exc:
-                return SetParametersResult(successful=False, reason=str(exc))
-        return SetParametersResult(successful=True)
-
     # ── Connection management ──────────────────────────────────────────────
 
     def _try_connect(self) -> None:
-        """Attempt to open the CAN interface; silently skip if already connected."""
         with self._lock:
             if self._connected:
                 return
             try:
-                bus = can.interface.Bus(
-                    channel=self._iface,
-                    bustype="socketcan",
-                )
-                self._bus = bus
+                self._bus = can.interface.Bus(channel=self._iface, bustype="socketcan")
                 self._connected = True
                 self.get_logger().info(f"CAN bus connected: {self._iface}")
                 self._publish_status("connected")
@@ -180,12 +143,10 @@ class CanBridgeNode(Node):
                 self._publish_status("disconnected")
 
     def _reconnect_cb(self) -> None:
-        """Periodic timer: try to reconnect when disconnected."""
         if not self._connected:
             self._try_connect()
 
     def _handle_can_error(self, exc: Exception, context: str) -> None:
-        """Mark bus as disconnected on any CAN error."""
         self.get_logger().warning(f"CAN error in {context}: {exc}")
         with self._lock:
             if self._bus is not None:
@@ -200,9 +161,8 @@ class CanBridgeNode(Node):
     # ── ROS callbacks ─────────────────────────────────────────────────────
 
     def _cmd_vel_cb(self, msg: Twist) -> None:
-        """Convert /cmd_vel Twist to VESC speed commands over CAN."""
+        """Convert /cmd_vel Twist to ORIN_CMD_DRIVE over CAN."""
         self._last_cmd_time = time.monotonic()
-
         if not self._connected:
             return
 
@@ -219,54 +179,40 @@ class CanBridgeNode(Node):
         right_mps = linear + angular
 
         payload = encode_velocity_cmd(left_mps, right_mps)
-        self._send_can(BALANCE_CMD_VELOCITY, payload, "cmd_vel")
+        self._send_can(MAMBA_CMD_VELOCITY, payload, "cmd_vel")
 
         # Keep ESP32-S3 BALANCE in DRIVE mode while receiving commands
-        self._send_can(BALANCE_CMD_MODE, encode_mode_cmd(MODE_DRIVE), "cmd_vel mode")
+        self._send_can(MAMBA_CMD_MODE, encode_mode_cmd(MODE_DRIVE), "cmd_vel mode")
 
     def _estop_cb(self, msg: Bool) -> None:
         """Forward /estop to ESP32-S3 BALANCE over CAN."""
         if not self._connected:
             return
-        payload = encode_estop_cmd(msg.data)
-        self._send_can(BALANCE_CMD_ESTOP, payload, "estop")
         if msg.data:
             self._send_can(
-                BALANCE_CMD_MODE, encode_mode_cmd(MODE_ESTOP), "estop mode"
+                MAMBA_CMD_MODE, encode_mode_cmd(MODE_ESTOP), "estop mode"
             )
             self.get_logger().warning("E-stop asserted — sent ESTOP to ESP32-S3 BALANCE")
 
     # ── Watchdog ──────────────────────────────────────────────────────────
 
     def _watchdog_cb(self) -> None:
-        """If no /cmd_vel arrives within the timeout, send zero velocity."""
+        """If /cmd_vel is silent for command_timeout_s, send zero DRIVE (acts as keepalive)."""
         if not self._connected:
             return
-        elapsed = time.monotonic() - self._last_cmd_time
-        if elapsed > self._cmd_timeout:
-            self._send_can(
-                BALANCE_CMD_VELOCITY,
-                encode_velocity_cmd(0.0, 0.0),
-                "watchdog zero-vel",
-            )
-            self._send_can(
-                BALANCE_CMD_MODE, encode_mode_cmd(MODE_IDLE), "watchdog idle"
-            )
+        if time.monotonic() - self._last_cmd_time > self._cmd_timeout:
+            self._send_can(ORIN_CMD_DRIVE, encode_drive_cmd(0, 0, MODE_IDLE), "watchdog")
 
     # ── CAN send helper ───────────────────────────────────────────────────
 
-    def _send_can(self, arb_id: int, data: bytes, context: str) -> None:
-        """Send a standard CAN frame; handle errors gracefully."""
+    def _send_can(self, arb_id: int, data: bytes, context: str,
+                  extended: bool = False) -> None:
         with self._lock:
             if not self._connected or self._bus is None:
                 return
             bus = self._bus
-
-        msg = can.Message(
-            arbitration_id=arb_id,
-            data=data,
-            is_extended_id=False,
-        )
+        msg = can.Message(arbitration_id=arb_id, data=data,
+                          is_extended_id=extended)
         try:
             bus.send(msg, timeout=0.05)
         except can.CanError as exc:
@@ -275,55 +221,41 @@ class CanBridgeNode(Node):
     # ── Background CAN reader ─────────────────────────────────────────────
 
     def _reader_loop(self) -> None:
-        """
-        Blocking CAN read loop executed in a daemon thread.
-        Dispatches incoming frames to the appropriate handler.
-        """
         while rclpy.ok():
             with self._lock:
-                connected = self._connected
-                bus = self._bus
-
+                connected, bus = self._connected, self._bus
             if not connected or bus is None:
                 time.sleep(0.1)
                 continue
-
             try:
                 frame = bus.recv(timeout=0.5)
             except can.CanError as exc:
                 self._handle_can_error(exc, "reader_loop recv")
                 continue
-
             if frame is None:
-                # Timeout — no frame within 0.5 s, loop again
                 continue
-
             self._dispatch_frame(frame)
 
     def _dispatch_frame(self, frame: can.Message) -> None:
-        """Route an incoming CAN frame to the correct publisher."""
         arb_id = frame.arbitration_id
         data   = bytes(frame.data)
-
+        vesc_l = (VESC_STATUS_1 << 8) | self._left_vesc_id
+        vesc_r = (VESC_STATUS_1 << 8) | self._right_vesc_id
         try:
-            if arb_id == BALANCE_TELEM_IMU:
-                self._handle_imu(data, frame.timestamp)
-
-            elif arb_id == BALANCE_TELEM_BATTERY:
-                self._handle_battery(data, frame.timestamp)
-
-            elif arb_id == VESC_TELEM_STATE + self._left_vesc_id:
-                self._handle_vesc_state(data, frame.timestamp, side="left")
-
-            elif arb_id == VESC_TELEM_STATE + self._right_vesc_id:
-                self._handle_vesc_state(data, frame.timestamp, side="right")
-
-            elif arb_id == ORIN_CAN_ID_FC_PID_ACK:
-                gains = decode_pid_ack(data)
-                self.get_logger().debug(
-                    f"FC PID ACK: Kp={gains.kp:.2f} Ki={gains.ki:.2f} Kd={gains.kd:.2f}"
-                )
-
+            if arb_id == ESP32_TELEM_ATTITUDE:
+                self._handle_attitude(data)
+            elif arb_id == ESP32_TELEM_BATTERY:
+                self._handle_battery(data)
+            elif arb_id == vesc_l:
+                t = decode_vesc_status1(self._left_vesc_id, data)
+                m = Float32MultiArray()
+                m.data = [t.erpm, t.duty, 0.0, t.current]
+                self._pub_vesc_left.publish(m)
+            elif arb_id == vesc_r:
+                t = decode_vesc_status1(self._right_vesc_id, data)
+                m = Float32MultiArray()
+                m.data = [t.erpm, t.duty, 0.0, t.current]
+                self._pub_vesc_right.publish(m)
         except Exception as exc:
             self.get_logger().warning(
                 f"Error parsing CAN frame 0x{arb_id:03X}: {exc}"
@@ -331,52 +263,36 @@ class CanBridgeNode(Node):
 
     # ── Frame handlers ────────────────────────────────────────────────────
 
-    def _handle_imu(self, data: bytes, timestamp: float) -> None:
-        telem = decode_imu_telem(data)
+    _STATE_LABEL = {0: "IDLE", 1: "RUNNING", 2: "FAULT"}
 
-        msg = Imu()
-        msg.header.stamp = self.get_clock().now().to_msg()
-        msg.header.frame_id = "imu_link"
-
-        msg.linear_acceleration.x = telem.accel_x
-        msg.linear_acceleration.y = telem.accel_y
-        msg.linear_acceleration.z = telem.accel_z
-
-        msg.angular_velocity.x = telem.gyro_x
-        msg.angular_velocity.y = telem.gyro_y
-        msg.angular_velocity.z = telem.gyro_z
-
-        # Covariance unknown; mark as -1 per REP-145
-        msg.orientation_covariance[0] = -1.0
-
-        self._pub_imu.publish(msg)
-
-    def _handle_battery(self, data: bytes, timestamp: float) -> None:
-        telem = decode_battery_telem(data)
+    def _handle_attitude(self, data: bytes) -> None:
+        """ATTITUDE (0x400): pitch, speed, yaw_rate, state, flags → /saltybot/attitude."""
+        t = decode_attitude(data)
+        now = self.get_clock().now().to_msg()
+        payload = {
+            "pitch_deg":  round(t.pitch_deg, 2),
+            "speed_mps":  round(t.speed, 3),
+            "yaw_rate":   round(t.yaw_rate, 3),
+            "state":      t.state,
+            "state_label": self._STATE_LABEL.get(t.state, f"UNKNOWN({t.state})"),
+            "flags":      t.flags,
+            "ts":         f"{now.sec}.{now.nanosec:09d}",
+        }
+        msg = String()
+        msg.data = json.dumps(payload)
+        self._pub_attitude.publish(msg)
+        self._pub_balance.publish(msg)   # keep /saltybot/balance_state alive
 
+    def _handle_battery(self, data: bytes) -> None:
+        """BATTERY (0x401): vbat_mv, fault_code, rssi → /can/battery."""
+        t = decode_battery(data)
         msg = BatteryState()
         msg.header.stamp = self.get_clock().now().to_msg()
-        msg.voltage = telem.voltage
-        msg.current = telem.current
+        msg.voltage = t.vbat_mv / 1000.0
         msg.present = True
         msg.power_supply_status = BatteryState.POWER_SUPPLY_STATUS_DISCHARGING
-
         self._pub_battery.publish(msg)
 
-    def _handle_vesc_state(
-        self, data: bytes, timestamp: float, side: str
-    ) -> None:
-        telem = decode_vesc_state(data)
-
-        msg = Float32MultiArray()
-        # Layout: [erpm, duty, voltage, current]
-        msg.data = [telem.erpm, telem.duty, telem.voltage, telem.current]
-
-        if side == "left":
-            self._pub_vesc_left.publish(msg)
-        else:
-            self._pub_vesc_right.publish(msg)
-
     # ── Status helper ─────────────────────────────────────────────────────
 
     def _publish_status(self, status: str) -> None:
@@ -387,17 +303,10 @@ class CanBridgeNode(Node):
     # ── Shutdown ──────────────────────────────────────────────────────────
 
     def destroy_node(self) -> None:
-        """Send zero velocity and shut down the CAN bus cleanly."""
         if self._connected and self._bus is not None:
             try:
-                self._send_can(
-                    BALANCE_CMD_VELOCITY,
-                    encode_velocity_cmd(0.0, 0.0),
-                    "shutdown",
-                )
-                self._send_can(
-                    BALANCE_CMD_MODE, encode_mode_cmd(MODE_IDLE), "shutdown"
-                )
+                self._send_can(ORIN_CMD_DRIVE, encode_drive_cmd(0, 0, MODE_IDLE), "shutdown")
+                self._send_can(ORIN_CMD_ARM,   encode_arm_cmd(False), "shutdown")
             except Exception:
                 pass
             try:
@@ -407,8 +316,6 @@ class CanBridgeNode(Node):
         super().destroy_node()
 
 
-# ---------------------------------------------------------------------------
-
 def main(args=None) -> None:
     rclpy.init(args=args)
     node = CanBridgeNode()

jetson/ros2_ws/src/saltybot_can_bridge/setup.py

@@ -15,7 +15,11 @@ setup(
     zip_safe=True,
     maintainer="sl-controls",
     maintainer_email="sl-controls@saltylab.local",
+<<<<<<< HEAD
+    description="CAN bus bridge for ESP32 IO motor controller and VESC telemetry",
+=======
     description="CAN bus bridge for ESP32-S3 BALANCE controller and VESC telemetry",
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
     license="MIT",
     tests_require=["pytest"],
     entry_points={

jetson/ros2_ws/src/saltybot_can_bridge/test/test_can_bridge.py

@@ -12,11 +12,11 @@ import struct
 import unittest
 
 from saltybot_can_bridge.balance_protocol import (
-    BALANCE_CMD_ESTOP,
-    BALANCE_CMD_MODE,
-    BALANCE_CMD_VELOCITY,
-    BALANCE_TELEM_BATTERY,
-    BALANCE_TELEM_IMU,
+    MAMBA_CMD_ESTOP,
+    MAMBA_CMD_MODE,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_TELEM_BATTERY,
+    MAMBA_TELEM_IMU,
     VESC_TELEM_STATE,
     MODE_DRIVE,
     MODE_ESTOP,
@@ -37,13 +37,13 @@ class TestMessageIDs(unittest.TestCase):
     """Verify the CAN message ID constants are correct."""
 
     def test_command_ids(self):
-        self.assertEqual(BALANCE_CMD_VELOCITY, 0x100)
-        self.assertEqual(BALANCE_CMD_MODE, 0x101)
-        self.assertEqual(BALANCE_CMD_ESTOP, 0x102)
+        self.assertEqual(MAMBA_CMD_VELOCITY, 0x100)
+        self.assertEqual(MAMBA_CMD_MODE, 0x101)
+        self.assertEqual(MAMBA_CMD_ESTOP, 0x102)
 
     def test_telemetry_ids(self):
-        self.assertEqual(BALANCE_TELEM_IMU, 0x200)
-        self.assertEqual(BALANCE_TELEM_BATTERY, 0x201)
+        self.assertEqual(MAMBA_TELEM_IMU, 0x200)
+        self.assertEqual(MAMBA_TELEM_BATTERY, 0x201)
         self.assertEqual(VESC_TELEM_STATE, 0x300)
 
 

jetson/ros2_ws/src/saltybot_can_e2e_test/saltybot_can_e2e_test/protocol_defs.py

@@ -4,28 +4,31 @@ protocol_defs.py — CAN message ID constants and frame builders/parsers for the
 Orin↔ESP32-S3 BALANCE↔VESC integration test suite.
 
 All IDs and payload formats are derived from:
-  include/orin_can.h   — Orin↔ESP32-S3 BALANCE protocol
+  include/orin_can.h   — Orin↔FC (ESP32-S3 BALANCE) protocol
   include/vesc_can.h   — VESC CAN protocol
   saltybot_can_bridge/balance_protocol.py — existing bridge constants
 
 CAN IDs used in tests
 ---------------------
-Orin → ESP32-S3 BALANCE commands (standard 11-bit, matching orin_can.h):
+Orin → FC (ESP32-S3 BALANCE) commands (standard 11-bit, matching orin_can.h):
   ORIN_CMD_HEARTBEAT  0x300
   ORIN_CMD_DRIVE      0x301    int16 speed (−1000..+1000), int16 steer (−1000..+1000)
   ORIN_CMD_MODE       0x302    uint8 mode byte
   ORIN_CMD_ESTOP      0x303    uint8 action (1=ESTOP, 0=CLEAR)
 
-ESP32-S3 BALANCE → Orin telemetry (standard 11-bit, matching orin_can.h):
+FC (ESP32-S3 BALANCE) → Orin telemetry (standard 11-bit, matching orin_can.h):
   FC_STATUS           0x400    8 bytes (see orin_can_fc_status_t)
   FC_VESC             0x401    8 bytes (see orin_can_fc_vesc_t)
   FC_IMU              0x402    8 bytes
   FC_BARO             0x403    8 bytes
 
+Mamba ↔ VESC internal commands (matching balance_protocol.py):
+=======
 ESP32-S3 BALANCE ↔ VESC internal commands (matching balance_protocol.py):
-  BALANCE_CMD_VELOCITY  0x100    8 bytes  left_mps (f32) | right_mps (f32) big-endian
-  BALANCE_CMD_MODE      0x101    1 byte   mode (0=idle,1=drive,2=estop)
-  BALANCE_CMD_ESTOP     0x102    1 byte   0x01=stop
+>>>>>>> 9aed963 (fix: scrub remaining Mamba references in can_bridge and e2e test protocol files)
+  MAMBA_CMD_VELOCITY  0x100    8 bytes  left_mps (f32) | right_mps (f32) big-endian
+  MAMBA_CMD_MODE      0x101    1 byte   mode (0=idle,1=drive,2=estop)
+  MAMBA_CMD_ESTOP     0x102    1 byte   0x01=stop
 
 VESC STATUS (extended 29-bit, matching vesc_can.h):
   arb_id = (VESC_PKT_STATUS << 8) | vesc_node_id  = (9 << 8) | node_id
@@ -36,7 +39,7 @@ import struct
 from typing import Tuple
 
 # ---------------------------------------------------------------------------
-# Orin → ESP32-S3 BALANCE command IDs  (from orin_can.h)
+# Orin → FC (ESP32-S3 BALANCE) command IDs  (from orin_can.h)
 # ---------------------------------------------------------------------------
 
 ORIN_CMD_HEARTBEAT: int = 0x300
@@ -45,7 +48,7 @@ ORIN_CMD_MODE: int      = 0x302
 ORIN_CMD_ESTOP: int     = 0x303
 
 # ---------------------------------------------------------------------------
-# ESP32-S3 BALANCE → Orin telemetry IDs  (from orin_can.h)
+# FC (ESP32-S3 BALANCE) → Orin telemetry IDs  (from orin_can.h)
 # ---------------------------------------------------------------------------
 
 FC_STATUS: int = 0x400
@@ -54,15 +57,18 @@ FC_IMU: int    = 0x402
 FC_BARO: int   = 0x403
 
 # ---------------------------------------------------------------------------
+# Mamba → VESC internal command IDs  (from balance_protocol.py)
+=======
 # ESP32-S3 BALANCE → VESC internal command IDs  (from balance_protocol.py)
+>>>>>>> 9aed963 (fix: scrub remaining Mamba references in can_bridge and e2e test protocol files)
 # ---------------------------------------------------------------------------
 
-BALANCE_CMD_VELOCITY: int = 0x100
-BALANCE_CMD_MODE: int     = 0x101
-BALANCE_CMD_ESTOP: int    = 0x102
+MAMBA_CMD_VELOCITY: int = 0x100
+MAMBA_CMD_MODE: int     = 0x101
+MAMBA_CMD_ESTOP: int    = 0x102
 
-BALANCE_TELEM_IMU: int     = 0x200
-BALANCE_TELEM_BATTERY: int = 0x201
+MAMBA_TELEM_IMU: int     = 0x200
+MAMBA_TELEM_BATTERY: int = 0x201
 VESC_TELEM_STATE: int    = 0x300
 
 # ---------------------------------------------------------------------------
@@ -136,12 +142,15 @@ def build_estop_cmd(action: int = 1) -> bytes:
 
 
 # ---------------------------------------------------------------------------
+# Frame builders — Mamba velocity commands (balance_protocol.py encoding)
+=======
 # Frame builders — ESP32-S3 BALANCE velocity commands (balance_protocol.py encoding)
+>>>>>>> 9aed963 (fix: scrub remaining Mamba references in can_bridge and e2e test protocol files)
 # ---------------------------------------------------------------------------
 
 def build_velocity_cmd(left_mps: float, right_mps: float) -> bytes:
     """
-    Build a BALANCE_CMD_VELOCITY payload (8 bytes, 2 × float32 big-endian).
+    Build a MAMBA_CMD_VELOCITY payload (8 bytes, 2 × float32 big-endian).
 
     Matches encode_velocity_cmd() in balance_protocol.py.
     """
@@ -303,12 +312,12 @@ def parse_vesc_status(data: bytes):
 
 def parse_velocity_cmd(data: bytes) -> Tuple[float, float]:
     """
-    Parse a BALANCE_CMD_VELOCITY payload (8 bytes, 2 × float32 big-endian).
+    Parse a MAMBA_CMD_VELOCITY payload (8 bytes, 2 × float32 big-endian).
 
     Returns
     -------
     (left_mps, right_mps)
     """
     if len(data) < 8:
-        raise ValueError(f"BALANCE_CMD_VELOCITY needs 8 bytes, got {len(data)}")
+        raise ValueError(f"MAMBA_CMD_VELOCITY needs 8 bytes, got {len(data)}")
     return struct.unpack(">ff", data[:8])

jetson/ros2_ws/src/saltybot_can_e2e_test/test/test_drive_command.py

@@ -14,8 +14,8 @@ import struct
 import pytest
 
 from saltybot_can_e2e_test.protocol_defs import (
-    BALANCE_CMD_VELOCITY,
-    BALANCE_CMD_MODE,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_CMD_MODE,
     FC_VESC,
     MODE_DRIVE,
     MODE_IDLE,
@@ -50,8 +50,8 @@ def _send_drive(bus, left_mps: float, right_mps: float) -> None:
             self.data = bytearray(data)
             self.is_extended_id = False
 
-    bus.send(_Msg(BALANCE_CMD_VELOCITY, payload))
-    bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
+    bus.send(_Msg(MAMBA_CMD_VELOCITY, payload))
+    bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
 
 
 # ---------------------------------------------------------------------------
@@ -62,11 +62,11 @@ class TestDriveForward:
     def test_drive_forward_velocity_frame_sent(self, mock_can_bus):
         """
         Inject DRIVE cmd (1.0 m/s, 1.0 m/s) → verify ESP32-S3 BALANCE receives
-        a BALANCE_CMD_VELOCITY frame with correct payload.
+        a MAMBA_CMD_VELOCITY frame with correct payload.
         """
         _send_drive(mock_can_bus, 1.0, 1.0)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1, "Expected exactly one velocity command frame"
 
         left, right = parse_velocity_cmd(bytes(vel_frames[0].data))
@@ -77,7 +77,7 @@ class TestDriveForward:
         """After a drive command, a MODE=drive frame must accompany it."""
         _send_drive(mock_can_bus, 1.0, 1.0)
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert len(mode_frames) >= 1, "Expected at least one MODE frame"
         assert bytes(mode_frames[0].data) == bytes([MODE_DRIVE])
 
@@ -109,7 +109,7 @@ class TestDriveTurn:
         """
         _send_drive(mock_can_bus, 0.5, -0.5)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1
 
         left, right = parse_velocity_cmd(bytes(vel_frames[0].data))
@@ -142,7 +142,7 @@ class TestDriveZero:
 
         _send_drive(mock_can_bus, 0.0, 0.0)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1
         left, right = parse_velocity_cmd(bytes(vel_frames[0].data))
         assert abs(left) < 1e-5,  "Left motor not stopped"
@@ -156,7 +156,7 @@ class TestDriveCmdTimeout:
         zero velocity is sent.  We test the encoding directly (without timers).
         """
         # The watchdog in CanBridgeNode calls encode_velocity_cmd(0.0, 0.0) and
-        # sends it on BALANCE_CMD_VELOCITY.  Replicate that here.
+        # sends it on MAMBA_CMD_VELOCITY.  Replicate that here.
         zero_payload = encode_velocity_cmd(0.0, 0.0)
 
         class _Msg:
@@ -165,16 +165,16 @@ class TestDriveCmdTimeout:
                 self.data = bytearray(data)
                 self.is_extended_id = False
 
-        mock_can_bus.send(_Msg(BALANCE_CMD_VELOCITY, zero_payload))
-        mock_can_bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_IDLE)))
+        mock_can_bus.send(_Msg(MAMBA_CMD_VELOCITY, zero_payload))
+        mock_can_bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_IDLE)))
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1
         left, right = parse_velocity_cmd(bytes(vel_frames[0].data))
         assert abs(left) < 1e-5
         assert abs(right) < 1e-5
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert len(mode_frames) == 1
         assert bytes(mode_frames[0].data) == bytes([MODE_IDLE])
 

jetson/ros2_ws/src/saltybot_can_e2e_test/test/test_estop.py

@@ -17,9 +17,9 @@ import pytest
 
 from saltybot_can_e2e_test.can_mock import MockCANBus
 from saltybot_can_e2e_test.protocol_defs import (
-    BALANCE_CMD_VELOCITY,
-    BALANCE_CMD_MODE,
-    BALANCE_CMD_ESTOP,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_CMD_MODE,
+    MAMBA_CMD_ESTOP,
     ORIN_CMD_ESTOP,
     FC_STATUS,
     MODE_IDLE,
@@ -68,16 +68,16 @@ class EstopStateMachine:
         """Send ESTOP and transition to estop mode."""
         self._estop_active = True
         self._mode = MODE_ESTOP
-        self._bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
-        self._bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_ESTOP)))
-        self._bus.send(_Msg(BALANCE_CMD_ESTOP, encode_estop_cmd(True)))
+        self._bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
+        self._bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_ESTOP)))
+        self._bus.send(_Msg(MAMBA_CMD_ESTOP, encode_estop_cmd(True)))
 
     def clear_estop(self) -> None:
         """Clear ESTOP and return to IDLE mode."""
         self._estop_active = False
         self._mode = MODE_IDLE
-        self._bus.send(_Msg(BALANCE_CMD_ESTOP, encode_estop_cmd(False)))
-        self._bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_IDLE)))
+        self._bus.send(_Msg(MAMBA_CMD_ESTOP, encode_estop_cmd(False)))
+        self._bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_IDLE)))
 
     def send_drive(self, left_mps: float, right_mps: float) -> None:
         """Send velocity command only if ESTOP is not active."""
@@ -85,8 +85,8 @@ class EstopStateMachine:
             # Bridge silently drops commands while estopped
             return
         self._mode = MODE_DRIVE
-        self._bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(left_mps, right_mps)))
-        self._bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
+        self._bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(left_mps, right_mps)))
+        self._bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
 
     @property
     def estop_active(self) -> bool:
@@ -105,7 +105,7 @@ class TestEstopHaltsMotors:
         sm = EstopStateMachine(mock_can_bus)
         sm.assert_estop()
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) >= 1, "No velocity frame after ESTOP"
         l, r = parse_velocity_cmd(bytes(vel_frames[-1].data))
         assert abs(l) < 1e-5, f"Left motor {l} not zero after ESTOP"
@@ -116,17 +116,17 @@ class TestEstopHaltsMotors:
         sm = EstopStateMachine(mock_can_bus)
         sm.assert_estop()
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert any(
             bytes(f.data) == bytes([MODE_ESTOP]) for f in mode_frames
         ), "MODE=ESTOP not found in sent frames"
 
     def test_estop_flag_byte_is_0x01(self, mock_can_bus):
-        """BALANCE_CMD_ESTOP payload must be 0x01 when asserting e-stop."""
+        """MAMBA_CMD_ESTOP payload must be 0x01 when asserting e-stop."""
         sm = EstopStateMachine(mock_can_bus)
         sm.assert_estop()
 
-        estop_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_ESTOP)
+        estop_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_ESTOP)
         assert len(estop_frames) >= 1
         assert bytes(estop_frames[-1].data) == b"\x01", \
             f"ESTOP payload {estop_frames[-1].data!r} != 0x01"
@@ -143,7 +143,7 @@ class TestEstopPersists:
 
         sm.send_drive(1.0, 1.0)   # should be suppressed
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 0, \
             "Velocity command was forwarded while ESTOP is active"
 
@@ -158,7 +158,7 @@ class TestEstopPersists:
         sm.send_drive(0.5, 0.5)
 
         # No mode frames should have been emitted (drive was suppressed)
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert all(
             bytes(f.data) != bytes([MODE_DRIVE]) for f in mode_frames
         ), "MODE=DRIVE was set despite active ESTOP"
@@ -174,19 +174,19 @@ class TestEstopClear:
 
         sm.send_drive(0.8, 0.8)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1, "Velocity command not sent after ESTOP clear"
         l, r = parse_velocity_cmd(bytes(vel_frames[0].data))
         assert abs(l - 0.8) < 1e-4
         assert abs(r - 0.8) < 1e-4
 
     def test_estop_clear_flag_byte_is_0x00(self, mock_can_bus):
-        """BALANCE_CMD_ESTOP payload must be 0x00 when clearing e-stop."""
+        """MAMBA_CMD_ESTOP payload must be 0x00 when clearing e-stop."""
         sm = EstopStateMachine(mock_can_bus)
         sm.assert_estop()
         sm.clear_estop()
 
-        estop_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_ESTOP)
+        estop_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_ESTOP)
         assert len(estop_frames) >= 2
         # Last ESTOP frame should be the clear
         assert bytes(estop_frames[-1].data) == b"\x00", \
@@ -198,7 +198,7 @@ class TestEstopClear:
         sm.assert_estop()
         sm.clear_estop()
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         last_mode = bytes(mode_frames[-1].data)
         assert last_mode == bytes([MODE_IDLE]), \
             f"Mode after ESTOP clear is {last_mode!r}, expected MODE_IDLE"

jetson/ros2_ws/src/saltybot_can_e2e_test/test/test_heartbeat_timeout.py

@@ -21,9 +21,9 @@ from saltybot_can_e2e_test.protocol_defs import (
     ORIN_CMD_HEARTBEAT,
     ORIN_CMD_ESTOP,
     ORIN_CMD_MODE,
-    BALANCE_CMD_VELOCITY,
-    BALANCE_CMD_MODE,
-    BALANCE_CMD_ESTOP,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_CMD_MODE,
+    MAMBA_CMD_ESTOP,
     MODE_IDLE,
     MODE_DRIVE,
     MODE_ESTOP,
@@ -100,9 +100,9 @@ def _simulate_estop_on_timeout(bus: MockCANBus) -> None:
             self.data = bytearray(data)
             self.is_extended_id = False
 
-    bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
-    bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_ESTOP)))
-    bus.send(_Msg(BALANCE_CMD_ESTOP, encode_estop_cmd(True)))
+    bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
+    bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_ESTOP)))
+    bus.send(_Msg(MAMBA_CMD_ESTOP, encode_estop_cmd(True)))
 
 
 # ---------------------------------------------------------------------------
@@ -121,25 +121,25 @@ class TestHeartbeatLoss:
         # Simulate bridge detecting timeout and escalating
         _simulate_estop_on_timeout(mock_can_bus)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) >= 1, "Zero velocity not sent after timeout"
         l, r = parse_velocity_cmd(bytes(vel_frames[-1].data))
         assert abs(l) < 1e-5, "Left not zero on timeout"
         assert abs(r) < 1e-5, "Right not zero on timeout"
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert any(
             bytes(f.data) == bytes([MODE_ESTOP]) for f in mode_frames
         ), "ESTOP mode not asserted on heartbeat timeout"
 
-        estop_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_ESTOP)
+        estop_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_ESTOP)
         assert len(estop_frames) >= 1, "ESTOP command not sent"
         assert bytes(estop_frames[0].data) == b"\x01"
 
     def test_heartbeat_loss_zero_velocity(self, mock_can_bus):
         """Zero velocity frame must appear among sent frames after timeout."""
         _simulate_estop_on_timeout(mock_can_bus)
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) >= 1
         for f in vel_frames:
             l, r = parse_velocity_cmd(bytes(f.data))
@@ -165,20 +165,20 @@ class TestHeartbeatRecovery:
         mock_can_bus.reset()
 
         # Phase 2: recovery — clear estop, restore drive mode
-        mock_can_bus.send(_Msg(BALANCE_CMD_ESTOP, encode_estop_cmd(False)))
-        mock_can_bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
-        mock_can_bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(0.5, 0.5)))
+        mock_can_bus.send(_Msg(MAMBA_CMD_ESTOP, encode_estop_cmd(False)))
+        mock_can_bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(MODE_DRIVE)))
+        mock_can_bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(0.5, 0.5)))
 
-        estop_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_ESTOP)
+        estop_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_ESTOP)
         assert any(bytes(f.data) == b"\x00" for f in estop_frames), \
             "ESTOP clear not sent on recovery"
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert any(
             bytes(f.data) == bytes([MODE_DRIVE]) for f in mode_frames
         ), "DRIVE mode not restored after recovery"
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) >= 1
         l, r = parse_velocity_cmd(bytes(vel_frames[-1].data))
         assert abs(l - 0.5) < 1e-4

jetson/ros2_ws/src/saltybot_can_e2e_test/test/test_mode_switching.py

@@ -17,9 +17,9 @@ import pytest
 
 from saltybot_can_e2e_test.can_mock import MockCANBus
 from saltybot_can_e2e_test.protocol_defs import (
-    BALANCE_CMD_VELOCITY,
-    BALANCE_CMD_MODE,
-    BALANCE_CMD_ESTOP,
+    MAMBA_CMD_VELOCITY,
+    MAMBA_CMD_MODE,
+    MAMBA_CMD_ESTOP,
     MODE_IDLE,
     MODE_DRIVE,
     MODE_ESTOP,
@@ -64,12 +64,12 @@ class ModeStateMachine:
 
         prev_mode = self._mode
         self._mode = mode
-        self._bus.send(_Msg(BALANCE_CMD_MODE, encode_mode_cmd(mode)))
+        self._bus.send(_Msg(MAMBA_CMD_MODE, encode_mode_cmd(mode)))
 
         # Side-effects of entering ESTOP from DRIVE
         if mode == MODE_ESTOP and prev_mode == MODE_DRIVE:
-            self._bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
-            self._bus.send(_Msg(BALANCE_CMD_ESTOP, encode_estop_cmd(True)))
+            self._bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(0.0, 0.0)))
+            self._bus.send(_Msg(MAMBA_CMD_ESTOP, encode_estop_cmd(True)))
 
         return True
 
@@ -79,7 +79,7 @@ class ModeStateMachine:
         """
         if self._mode != MODE_DRIVE:
             return False
-        self._bus.send(_Msg(BALANCE_CMD_VELOCITY, encode_velocity_cmd(left_mps, right_mps)))
+        self._bus.send(_Msg(MAMBA_CMD_VELOCITY, encode_velocity_cmd(left_mps, right_mps)))
         return True
 
     @property
@@ -97,7 +97,7 @@ class TestIdleToDrive:
         sm = ModeStateMachine(mock_can_bus)
         sm.set_mode(MODE_DRIVE)
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert len(mode_frames) == 1
         assert bytes(mode_frames[0].data) == bytes([MODE_DRIVE])
 
@@ -108,7 +108,7 @@ class TestIdleToDrive:
         forwarded = sm.send_drive(1.0, 1.0)
         assert forwarded is False, "Drive cmd should be blocked in IDLE mode"
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 0
 
     def test_drive_mode_allows_commands(self, mock_can_bus):
@@ -120,7 +120,7 @@ class TestIdleToDrive:
         forwarded = sm.send_drive(0.5, 0.5)
         assert forwarded is True
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 1
         l, r = parse_velocity_cmd(bytes(vel_frames[0].data))
         assert abs(l - 0.5) < 1e-4
@@ -137,7 +137,7 @@ class TestDriveToEstop:
 
         sm.set_mode(MODE_ESTOP)
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) >= 1, "No velocity frame on DRIVE→ESTOP transition"
         l, r = parse_velocity_cmd(bytes(vel_frames[-1].data))
         assert abs(l) < 1e-5, f"Left motor {l} not zero after ESTOP"
@@ -149,7 +149,7 @@ class TestDriveToEstop:
         sm.set_mode(MODE_DRIVE)
         sm.set_mode(MODE_ESTOP)
 
-        mode_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_MODE)
+        mode_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_MODE)
         assert any(bytes(f.data) == bytes([MODE_ESTOP]) for f in mode_frames)
 
     def test_estop_blocks_subsequent_drive(self, mock_can_bus):
@@ -162,7 +162,7 @@ class TestDriveToEstop:
         forwarded = sm.send_drive(1.0, 1.0)
         assert forwarded is False
 
-        vel_frames = mock_can_bus.get_sent_frames_by_id(BALANCE_CMD_VELOCITY)
+        vel_frames = mock_can_bus.get_sent_frames_by_id(MAMBA_CMD_VELOCITY)
         assert len(vel_frames) == 0
 
 

jetson/ros2_ws/src/saltybot_diagnostics/README.md

@@ -5,7 +5,11 @@ Comprehensive hardware diagnostics and health monitoring for SaltyBot.
 ## Features
 
 ### Startup Checks
+<<<<<<< HEAD
+- RPLIDAR, RealSense, VESC, Jabra mic, ESP32 BALANCE, servos
+=======
 - RPLIDAR, RealSense, VESC, Jabra mic, ESP32-S3, servos
+>>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
 - WiFi, GPS, disk space, RAM
 - Boot result TTS + face animation
 - JSON logging

jetson/ros2_ws/src/saltybot_dronecan_gps/config/dronecan_gps_params.yaml

@@ -0,0 +1,9 @@
+# dronecan_gps_params.yaml — CubePilot Here4 DroneCAN GPS driver defaults
+# Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+dronecan_gps:
+  ros__parameters:
+    can_interface:    "can0"
+    can_bitrate:      1000000   # Here4 default: 1Mbps DroneCAN
+    node_id:          127       # DroneCAN local node ID (GPS driver)
+    publish_compass:  true      # publish MagneticFieldStrength if available

jetson/ros2_ws/src/saltybot_dronecan_gps/config/here4_params.yaml

@@ -0,0 +1,22 @@
+here4_can_node:
+  ros__parameters:
+    # SocketCAN interface — freed from ESP32 BALANCE comms by bd-wim1
+    can_interface: can0
+
+    # DroneCAN bitrate — Here4 runs at 1 Mbps (not 500 kbps used previously)
+    bitrate: 1000000
+
+    # Local DroneCAN node ID for this Orin instance (1-127, must be unique on bus)
+    local_node_id: 126
+
+    # Set true to run: ip link set can0 type can bitrate 1000000 && ip link set can0 up
+    # Requires: sudo setcap cap_net_admin+eip $(which python3)  or  run as root
+    # Default false — manage interface externally (systemd-networkd or udev)
+    bring_up_can: false
+
+    # Here4 DroneCAN node ID — 0 means auto-detect from first Fix2 message
+    node_id_filter: 0
+
+    # TF frame IDs
+    fix_frame_id: gps
+    imu_frame_id: here4_imu

jetson/ros2_ws/src/saltybot_dronecan_gps/launch/here4.launch.py

@@ -0,0 +1,109 @@
+"""here4.launch.py — Launch the Here4 GPS DroneCAN bridge on CANable2.
+
+bd-p47c: CANable2 freed by bd-wim1 (ESP32 moved to UART/USB) now used for
+Here4 GPS at 1 Mbps DroneCAN/UAVCAN v0.
+
+CAN setup (one-time, survives reboot via systemd-networkd or udev)
+------------------------------------------------------------------
+  # Option A — manual (quick test):
+  sudo ip link set can0 down
+  sudo ip link set can0 type can bitrate 1000000
+  sudo ip link set can0 up
+
+  # Option B — let the node do it (requires CAP_NET_ADMIN):
+  ros2 launch saltybot_dronecan_gps here4.launch.py bring_up_can:=true
+
+  # Option C — systemd-networkd (/etc/systemd/network/80-can0.network):
+  [Match]
+  Name=can0
+  [CAN]
+  BitRate=1M
+
+Published topics
+----------------
+  /gps/fix             sensor_msgs/NavSatFix     → navsat_transform_node (EKF)
+  /gps/velocity        geometry_msgs/TwistWithCovarianceStamped
+  /here4/fix           sensor_msgs/NavSatFix     (alias)
+  /here4/imu           sensor_msgs/Imu
+  /here4/mag           sensor_msgs/MagneticField
+  /here4/baro          sensor_msgs/FluidPressure
+  /here4/status        std_msgs/String JSON
+  /here4/node_id       std_msgs/Int32
+
+Subscribed topics
+-----------------
+  /rtcm                std_msgs/ByteMultiArray   RTCM corrections (NTRIP client)
+  /rtcm_hex            std_msgs/String           hex-encoded RTCM (fallback)
+
+Usage
+-----
+  # Default (interface already up):
+  ros2 launch saltybot_dronecan_gps here4.launch.py
+
+  # Bring up interface automatically (CAP_NET_ADMIN required):
+  ros2 launch saltybot_dronecan_gps here4.launch.py bring_up_can:=true
+
+  # Override interface (e.g. second CAN adapter):
+  ros2 launch saltybot_dronecan_gps here4.launch.py can_interface:=can1
+
+  # Pin to specific Here4 node ID (skip auto-detect):
+  ros2 launch saltybot_dronecan_gps here4.launch.py node_id_filter:=10
+
+System dependency
+-----------------
+  pip install dronecan          # DroneCAN/UAVCAN v0 Python library
+  apt install can-utils         # optional: candump, cansend for debugging
+"""
+
+import os
+from ament_index_python.packages import get_package_share_directory
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
+from launch_ros.actions import Node
+
+
+def generate_launch_description() -> LaunchDescription:
+    pkg_share   = get_package_share_directory("saltybot_dronecan_gps")
+    params_file = os.path.join(pkg_share, "config", "here4_params.yaml")
+
+    args = [
+        DeclareLaunchArgument(
+            "can_interface",
+            default_value="can0",
+            description="SocketCAN interface (CANable2 @ 1 Mbps)",
+        ),
+        DeclareLaunchArgument(
+            "bring_up_can",
+            default_value="false",
+            description="Bring up can_interface via ip link (requires CAP_NET_ADMIN)",
+        ),
+        DeclareLaunchArgument(
+            "node_id_filter",
+            default_value="0",
+            description="DroneCAN node ID of Here4 (0=auto-detect from first Fix2)",
+        ),
+        DeclareLaunchArgument(
+            "local_node_id",
+            default_value="126",
+            description="DroneCAN node ID for this Orin (must be unique on bus)",
+        ),
+    ]
+
+    node = Node(
+        package="saltybot_dronecan_gps",
+        executable="here4_node",
+        name="here4_can_node",
+        output="screen",
+        parameters=[
+            params_file,
+            {
+                "can_interface":  LaunchConfiguration("can_interface"),
+                "bring_up_can":   LaunchConfiguration("bring_up_can"),
+                "node_id_filter": LaunchConfiguration("node_id_filter"),
+                "local_node_id":  LaunchConfiguration("local_node_id"),
+            },
+        ],
+    )
+
+    return LaunchDescription([*args, node])

jetson/ros2_ws/src/saltybot_dronecan_gps/launch/here4_gps.launch.py

@@ -0,0 +1,110 @@
+"""
+here4_gps.launch.py — CubePilot Here4 RTK GPS full stack
+Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+Launches:
+  - dronecan_gps_node   (saltybot_dronecan_gps)
+  - ntrip_client_node   (saltybot_ntrip_client)
+
+Usage (minimal):
+  ros2 launch saltybot_dronecan_gps here4_gps.launch.py \\
+    ntrip_mount:=RTCM3_GENERIC ntrip_user:=you@email.com
+
+Full options:
+  ros2 launch saltybot_dronecan_gps here4_gps.launch.py \\
+    can_interface:=can0 \\
+    can_bitrate:=1000000 \\
+    ntrip_caster:=rtk2go.com \\
+    ntrip_port:=2101 \\
+    ntrip_mount:=MYBASE \\
+    ntrip_user:=you@email.com \\
+    ntrip_password:=secret
+"""
+
+import os
+
+from ament_index_python.packages import get_package_share_directory
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
+from launch_ros.actions import Node
+
+
+def generate_launch_description() -> LaunchDescription:
+    gps_cfg = os.path.join(
+        get_package_share_directory('saltybot_dronecan_gps'),
+        'config', 'dronecan_gps_params.yaml',
+    )
+    ntrip_cfg = os.path.join(
+        get_package_share_directory('saltybot_ntrip_client'),
+        'config', 'ntrip_params.yaml',
+    )
+
+    return LaunchDescription([
+        # ── Shared CAN args ───────────────────────────────────────────────────
+        DeclareLaunchArgument(
+            'can_interface', default_value='can0',
+            description='SocketCAN interface name',
+        ),
+        DeclareLaunchArgument(
+            'can_bitrate', default_value='1000000',
+            description='CAN bus bitrate — Here4 default is 1000000 (1 Mbps)',
+        ),
+
+        # ── NTRIP args ────────────────────────────────────────────────────────
+        DeclareLaunchArgument(
+            'ntrip_caster', default_value='rtk2go.com',
+            description='NTRIP caster hostname',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_port', default_value='2101',
+            description='NTRIP caster port',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_mount', default_value='',
+            description='NTRIP mount point (REQUIRED)',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_user', default_value='',
+            description='NTRIP username (rtk2go.com requires email address)',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_password', default_value='',
+            description='NTRIP password',
+        ),
+
+        # ── DroneCAN GPS node ─────────────────────────────────────────────────
+        Node(
+            package='saltybot_dronecan_gps',
+            executable='dronecan_gps_node',
+            name='dronecan_gps',
+            output='screen',
+            parameters=[
+                gps_cfg,
+                {
+                    'can_interface': LaunchConfiguration('can_interface'),
+                    'can_bitrate':   LaunchConfiguration('can_bitrate'),
+                },
+            ],
+        ),
+
+        # ── NTRIP client node ─────────────────────────────────────────────────
+        Node(
+            package='saltybot_ntrip_client',
+            executable='ntrip_client_node',
+            name='ntrip_client',
+            output='screen',
+            parameters=[
+                ntrip_cfg,
+                {
+                    'can_interface':  LaunchConfiguration('can_interface'),
+                    'can_bitrate':    LaunchConfiguration('can_bitrate'),
+                    'ntrip_caster':   LaunchConfiguration('ntrip_caster'),
+                    'ntrip_port':     LaunchConfiguration('ntrip_port'),
+                    'ntrip_mount':    LaunchConfiguration('ntrip_mount'),
+                    'ntrip_user':     LaunchConfiguration('ntrip_user'),
+                    'ntrip_password': LaunchConfiguration('ntrip_password'),
+                },
+            ],
+        ),
+    ])

jetson/ros2_ws/src/saltybot_dronecan_gps/package.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0"?>
+<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
+<package format="3">
+  <name>saltybot_dronecan_gps</name>
+  <version>0.1.0</version>
+  <description>
+    DroneCAN/UAVCAN v0 bridge for Here4 GPS on the CANable2 SocketCAN adapter.
+    Publishes GPS fix, IMU, magnetometer, and barometer data to ROS2.
+    Injects RTCM corrections for RTK.
+
+    bd-p47c: CANable2 freed from ESP32 BALANCE comms by bd-wim1.
+    Here4 operates at 1 Mbps on can0 (was 500 kbps for VESC comms).
+
+    System dependency: dronecan Python library (pip install dronecan)
+  </description>
+  <maintainer email="sl-perception@saltylab.local">sl-perception</maintainer>
+  <license>MIT</license>
+
+  <exec_depend>rclpy</exec_depend>
+  <exec_depend>std_msgs</exec_depend>
+  <exec_depend>sensor_msgs</exec_depend>
+  <exec_depend>geometry_msgs</exec_depend>
+
+  <!-- dronecan: pip install dronecan  (DroneCAN/UAVCAN v0 Python library) -->
+  <!-- python3-can is a transitive dependency of dronecan -->
+
+  <buildtool_depend>ament_python</buildtool_depend>
+
+  <test_depend>ament_copyright</test_depend>
+  <test_depend>ament_flake8</test_depend>
+  <test_depend>ament_pep257</test_depend>
+  <test_depend>python3-pytest</test_depend>
+
+  <export>
+    <build_type>ament_python</build_type>
+  </export>
+</package>

jetson/ros2_ws/src/saltybot_dronecan_gps/resource/saltybot_dronecan_gps

@@ -0,0 +1 @@
+saltybot_dronecan_gps

jetson/ros2_ws/src/saltybot_dronecan_gps/saltybot_dronecan_gps/__init__.py

@@ -0,0 +1 @@
+# saltybot_dronecan_gps — Here4 GPS DroneCAN bridge for CANable2 (bd-p47c)

jetson/ros2_ws/src/saltybot_dronecan_gps/saltybot_dronecan_gps/dronecan_gps_node.py

@@ -0,0 +1,204 @@
+#!/usr/bin/env python3
+"""
+dronecan_gps_node.py — DroneCAN GPS driver for CubePilot Here4 RTK
+Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+Subscribes to:
+  uavcan.equipment.gnss.Fix2            (msg ID 1063) — position + fix status
+  uavcan.equipment.ahrs.MagneticFieldStrength          — compass (optional)
+
+Publishes:
+  /gps/fix        sensor_msgs/NavSatFix
+  /gps/vel        geometry_msgs/TwistStamped
+  /gps/rtk_status std_msgs/String
+
+DroneCAN fix_type → sensor_msgs status mapping:
+  0 = NO_FIX     → STATUS_NO_FIX  (-1)
+  1 = TIME_ONLY  → STATUS_NO_FIX  (-1)
+  2 = 2D_FIX    → STATUS_FIX      (0)
+  3 = 3D_FIX    → STATUS_FIX      (0)
+  4 = DGPS       → STATUS_SBAS_FIX (1)
+  5 = RTK_FLOAT  → STATUS_GBAS_FIX (2)
+  6 = RTK_FIXED  → STATUS_GBAS_FIX (2)
+"""
+
+import math
+import threading
+
+import rclpy
+from rclpy.node import Node
+from rclpy.qos import QoSProfile, ReliabilityPolicy, HistoryPolicy
+
+from sensor_msgs.msg import NavSatFix, NavSatStatus
+from geometry_msgs.msg import TwistStamped
+from std_msgs.msg import String
+
+try:
+    import dronecan
+except ImportError:
+    dronecan = None
+
+_SENSOR_QOS = QoSProfile(
+    reliability=ReliabilityPolicy.BEST_EFFORT,
+    history=HistoryPolicy.KEEP_LAST,
+    depth=5,
+)
+
+# DroneCAN fix_type → (NavSatStatus.status, rtk_label)
+_FIX_MAP = {
+    0: (NavSatStatus.STATUS_NO_FIX,   'NO_FIX'),
+    1: (NavSatStatus.STATUS_NO_FIX,   'TIME_ONLY'),
+    2: (NavSatStatus.STATUS_FIX,      '2D_FIX'),
+    3: (NavSatStatus.STATUS_FIX,      '3D_FIX'),
+    4: (NavSatStatus.STATUS_SBAS_FIX, 'DGPS'),
+    5: (NavSatStatus.STATUS_GBAS_FIX, 'RTK_FLOAT'),
+    6: (NavSatStatus.STATUS_GBAS_FIX, 'RTK_FIXED'),
+}
+
+
+class DroneCanGpsNode(Node):
+    def __init__(self) -> None:
+        super().__init__('dronecan_gps')
+
+        self.declare_parameter('can_interface', 'can0')
+        self.declare_parameter('can_bitrate', 1000000)
+        self.declare_parameter('node_id', 127)          # DroneCAN local node ID
+        self.declare_parameter('publish_compass', True)
+
+        self._iface = self.get_parameter('can_interface').value
+        self._bitrate = self.get_parameter('can_bitrate').value
+        self._node_id = self.get_parameter('node_id').value
+        self._publish_compass = self.get_parameter('publish_compass').value
+
+        self._fix_pub = self.create_publisher(NavSatFix, '/gps/fix', _SENSOR_QOS)
+        self._vel_pub = self.create_publisher(TwistStamped, '/gps/vel', _SENSOR_QOS)
+        self._rtk_pub = self.create_publisher(String, '/gps/rtk_status', 10)
+
+        if dronecan is None:
+            self.get_logger().error(
+                'python-dronecan not installed. '
+                'Run: pip install python-dronecan'
+            )
+            return
+
+        self._lock = threading.Lock()
+        self._dc_node = None
+        self._spin_thread = threading.Thread(
+            target=self._dronecan_spin, daemon=True
+        )
+        self._spin_thread.start()
+        self.get_logger().info(
+            f'DroneCanGpsNode started — interface={self._iface} '
+            f'bitrate={self._bitrate}'
+        )
+
+    # ── DroneCAN spin (runs in background thread) ─────────────────────────────
+
+    def _dronecan_spin(self) -> None:
+        try:
+            self._dc_node = dronecan.make_node(
+                self._iface,
+                node_id=self._node_id,
+                bitrate=self._bitrate,
+            )
+            self._dc_node.add_handler(
+                dronecan.uavcan.equipment.gnss.Fix2,
+                self._on_fix2,
+            )
+            if self._publish_compass:
+                self._dc_node.add_handler(
+                    dronecan.uavcan.equipment.ahrs.MagneticFieldStrength,
+                    self._on_mag,
+                )
+            self.get_logger().info(
+                f'DroneCAN node online on {self._iface}'
+            )
+            while rclpy.ok():
+                self._dc_node.spin(timeout=0.1)
+        except Exception as exc:
+            self.get_logger().error(f'DroneCAN spin error: {exc}')
+
+    # ── Message handlers ──────────────────────────────────────────────────────
+
+    def _on_fix2(self, event) -> None:
+        msg = event.message
+        now = self.get_clock().now().to_msg()
+
+        fix_type = int(msg.fix_type)
+        nav_status, rtk_label = _FIX_MAP.get(
+            fix_type, (NavSatStatus.STATUS_NO_FIX, 'UNKNOWN')
+        )
+
+        # NavSatFix
+        fix = NavSatFix()
+        fix.header.stamp = now
+        fix.header.frame_id = 'gps'
+        fix.status.status = nav_status
+        fix.status.service = NavSatStatus.SERVICE_GPS
+
+        fix.latitude = math.degrees(msg.latitude_deg_1e8 * 1e-8)
+        fix.longitude = math.degrees(msg.longitude_deg_1e8 * 1e-8)
+        fix.altitude = msg.height_msl_mm * 1e-3  # mm → m
+
+        # Covariance from position_covariance if available, else diagonal guess
+        if hasattr(msg, 'position_covariance') and len(msg.position_covariance) >= 9:
+            fix.position_covariance = list(msg.position_covariance)
+            fix.position_covariance_type = NavSatFix.COVARIANCE_TYPE_FULL
+        else:
+            h_var = (msg.horizontal_pos_accuracy_m_1e2 * 1e-2) ** 2 \
+                if hasattr(msg, 'horizontal_pos_accuracy_m_1e2') else 4.0
+            v_var = (msg.vertical_pos_accuracy_m_1e2 * 1e-2) ** 2 \
+                if hasattr(msg, 'vertical_pos_accuracy_m_1e2') else 4.0
+            fix.position_covariance = [
+                h_var, 0.0,   0.0,
+                0.0,   h_var, 0.0,
+                0.0,   0.0,   v_var,
+            ]
+            fix.position_covariance_type = NavSatFix.COVARIANCE_TYPE_DIAGONAL_KNOWN
+
+        self._fix_pub.publish(fix)
+
+        # TwistStamped velocity
+        if hasattr(msg, 'ned_velocity'):
+            vel = TwistStamped()
+            vel.header.stamp = now
+            vel.header.frame_id = 'gps'
+            vel.twist.linear.x = float(msg.ned_velocity[0])  # North m/s
+            vel.twist.linear.y = float(msg.ned_velocity[1])  # East  m/s
+            vel.twist.linear.z = float(msg.ned_velocity[2])  # Down  m/s (ROS: up+)
+            self._vel_pub.publish(vel)
+
+        # RTK status string
+        rtk_msg = String()
+        rtk_msg.data = rtk_label
+        self._rtk_pub.publish(rtk_msg)
+
+        self.get_logger().debug(
+            f'Fix2: {fix.latitude:.6f},{fix.longitude:.6f} '
+            f'alt={fix.altitude:.1f}m status={rtk_label}'
+        )
+
+    def _on_mag(self, event) -> None:
+        # Compass data logged; extend to publish /imu/mag if needed
+        msg = event.message
+        self.get_logger().debug(
+            f'Mag: {msg.magnetic_field_ga[0]:.3f} '
+            f'{msg.magnetic_field_ga[1]:.3f} '
+            f'{msg.magnetic_field_ga[2]:.3f} Ga'
+        )
+
+
+def main(args=None) -> None:
+    rclpy.init(args=args)
+    node = DroneCanGpsNode()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        node.destroy_node()
+        rclpy.shutdown()
+
+
+if __name__ == '__main__':
+    main()

jetson/ros2_ws/src/saltybot_dronecan_gps/saltybot_dronecan_gps/dronecan_parser.py

@@ -0,0 +1,333 @@
+"""dronecan_parser.py — Pure-Python conversion of DroneCAN/UAVCAN v0 message
+objects to plain Python dicts, independent of ROS2.
+
+Keeps the dronecan library dependency isolated so that unit tests can run
+without the dronecan package or CAN hardware.
+
+DroneCAN message types handled
+-------------------------------
+  uavcan.equipment.gnss.Fix2               DTID 1063
+  uavcan.equipment.gnss.Auxiliary          DTID 1060
+  uavcan.equipment.ahrs.RawIMU             DTID 1003
+  uavcan.equipment.ahrs.MagneticFieldStrength2  DTID 1001
+  uavcan.equipment.air_data.StaticPressure DTID 1028
+  uavcan.equipment.air_data.StaticTemperature DTID 1029
+  uavcan.protocol.NodeStatus               DTID 341
+  uavcan.equipment.gnss.RTCMStream         DTID 1062  (TX: RTCM injection)
+
+Fix2 status values
+------------------
+  0  NO_FIX
+  1  TIME_ONLY
+  2  2D_FIX
+  3  3D_FIX
+
+NodeStatus health / mode
+-------------------------
+  health  0=OK 1=WARNING 2=ERROR 3=CRITICAL
+  mode    0=OPERATIONAL 1=INITIALIZATION 2=MAINTENANCE 3=SOFTWARE_UPDATE 7=OFFLINE
+"""
+
+from __future__ import annotations
+
+from typing import Any, Dict, List, Optional
+
+# ── DSDL constants ────────────────────────────────────────────────────────────
+
+DTID_FIX2              = 1063
+DTID_AUXILIARY         = 1060
+DTID_RAW_IMU           = 1003
+DTID_MAG_FIELD         = 1001
+DTID_STATIC_PRESSURE   = 1028
+DTID_STATIC_TEMPERATURE = 1029
+DTID_NODE_STATUS       = 341
+DTID_RTCM_STREAM       = 1062
+
+# Fix2 status
+FIX_NO_FIX    = 0
+FIX_TIME_ONLY = 1
+FIX_2D        = 2
+FIX_3D        = 3
+
+FIX_LABEL = {FIX_NO_FIX: "NO_FIX", FIX_TIME_ONLY: "TIME_ONLY",
+             FIX_2D: "2D_FIX", FIX_3D: "3D_FIX"}
+
+# NodeStatus health
+HEALTH_OK       = 0
+HEALTH_WARNING  = 1
+HEALTH_ERROR    = 2
+HEALTH_CRITICAL = 3
+
+HEALTH_LABEL = {0: "OK", 1: "WARNING", 2: "ERROR", 3: "CRITICAL"}
+MODE_LABEL   = {0: "OPERATIONAL", 1: "INITIALIZATION", 2: "MAINTENANCE",
+                3: "SOFTWARE_UPDATE", 7: "OFFLINE"}
+
+# RTCM stream: max bytes per DroneCAN frame
+RTCM_MAX_CHUNK = 128
+
+
+# ── Helpers ───────────────────────────────────────────────────────────────────
+
+def _getf(obj: Any, *attrs: str, default: Any = None) -> Any:
+    """Get nested attribute with fallback, tolerant of dronecan proxy objects."""
+    for attr in attrs:
+        try:
+            obj = getattr(obj, attr)
+        except AttributeError:
+            return default
+    return obj
+
+
+def _list3(vec: Any, default: float = 0.0) -> List[float]:
+    """Convert a dronecan 3-element array to a plain list of floats."""
+    try:
+        return [float(vec[0]), float(vec[1]), float(vec[2])]
+    except (TypeError, IndexError):
+        return [default, default, default]
+
+
+def _list9(mat: Any, default: float = 0.0) -> List[float]:
+    """Convert a dronecan 9-element array (row-major 3×3) to a plain list."""
+    try:
+        return [float(mat[i]) for i in range(9)]
+    except (TypeError, IndexError):
+        return [default] * 9
+
+
+# ── Fix2 ─────────────────────────────────────────────────────────────────────
+
+def parse_fix2(msg: Any) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.equipment.gnss.Fix2 message.
+
+    Parameters
+    ----------
+    msg : dronecan message object (event.message / event.transfer.payload)
+
+    Returns
+    -------
+    dict with keys:
+        lat_deg        float   degrees (WGS84)
+        lon_deg        float   degrees (WGS84)
+        alt_msl_m      float   metres above MSL
+        alt_ellipsoid_m float  metres above WGS84 ellipsoid
+        ned_vel        list[3] [north, east, down] m/s
+        fix_type       int     0..3
+        fix_label      str
+        sats_used      int
+        pdop           float
+        hdop           float
+        vdop           float
+        pos_cov        list[9] row-major 3×3 position covariance, m²
+        undulation_m   float   WGS84 geoid undulation (m)
+        gnss_timestamp_us int  microseconds (GPS epoch)
+    """
+    if msg is None:
+        return None
+    try:
+        lat = float(_getf(msg, "latitude_deg_1e8",  default=0)) * 1e-8
+        lon = float(_getf(msg, "longitude_deg_1e8", default=0)) * 1e-8
+        alt_msl = float(_getf(msg, "height_msl_mm",       default=0)) * 1e-3
+        alt_ell = float(_getf(msg, "height_ellipsoid_mm",  default=0)) * 1e-3
+
+        ned = _list3(_getf(msg, "ned_velocity"))
+
+        fix_type = int(_getf(msg, "status", default=FIX_NO_FIX))
+
+        # sats_used is uint7, may be named differently across DSDL revisions
+        sats = int(_getf(msg, "sats_used", default=0))
+
+        pdop = float(_getf(msg, "pdop", default=99.0))
+        hdop = float(_getf(msg, "hdop", default=99.0))
+        vdop = float(_getf(msg, "vdop", default=99.0))
+        undulation = float(_getf(msg, "undulation", default=0.0))
+
+        # position_covariance: optional, may be absent in older DSDL
+        pos_cov_raw = _getf(msg, "position_covariance")
+        pos_cov = _list9(pos_cov_raw) if pos_cov_raw is not None else [0.0] * 9
+
+        gnss_ts = int(_getf(msg, "gnss_timestamp", default=0))
+
+        return {
+            "lat_deg":          lat,
+            "lon_deg":          lon,
+            "alt_msl_m":        alt_msl,
+            "alt_ellipsoid_m":  alt_ell,
+            "ned_vel":          ned,
+            "fix_type":         fix_type,
+            "fix_label":        FIX_LABEL.get(fix_type, f"UNKNOWN({fix_type})"),
+            "sats_used":        sats,
+            "pdop":             pdop,
+            "hdop":             hdop,
+            "vdop":             vdop,
+            "pos_cov":          pos_cov,
+            "undulation_m":     undulation,
+            "gnss_timestamp_us": gnss_ts,
+        }
+    except Exception:
+        return None
+
+
+# ── RawIMU ────────────────────────────────────────────────────────────────────
+
+def parse_raw_imu(msg: Any) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.equipment.ahrs.RawIMU message.
+
+    Returns
+    -------
+    dict with keys:
+        gyro_xyz     list[3]  rad/s
+        accel_xyz    list[3]  m/s²
+        dt_s         float    integration interval (seconds)
+        gyro_cov     list[9]  row-major 3×3 covariance
+        accel_cov    list[9]
+    """
+    if msg is None:
+        return None
+    try:
+        gyro  = _list3(_getf(msg, "rate_gyro_latest"))
+        accel = _list3(_getf(msg, "accelerometer_latest"))
+        dt    = float(_getf(msg, "integration_interval", default=0.0))
+
+        gyro_cov  = _list9(_getf(msg, "rate_gyro_covariance"))
+        accel_cov = _list9(_getf(msg, "accelerometer_covariance"))
+
+        return {
+            "gyro_xyz":  gyro,
+            "accel_xyz": accel,
+            "dt_s":      dt,
+            "gyro_cov":  gyro_cov,
+            "accel_cov": accel_cov,
+        }
+    except Exception:
+        return None
+
+
+# ── MagneticFieldStrength2 ────────────────────────────────────────────────────
+
+def parse_mag(msg: Any) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.equipment.ahrs.MagneticFieldStrength2 message.
+
+    Returns
+    -------
+    dict with keys:
+        sensor_id     int
+        field_ga      list[3]  [x, y, z] Gauss
+        field_cov     list[9]  row-major 3×3 covariance (Gauss²)
+    """
+    if msg is None:
+        return None
+    try:
+        sensor_id = int(_getf(msg, "sensor_id", default=0))
+        field_ga  = _list3(_getf(msg, "magnetic_field_ga"))
+        field_cov = _list9(_getf(msg, "magnetic_field_covariance"))
+        return {
+            "sensor_id": sensor_id,
+            "field_ga":  field_ga,
+            "field_cov": field_cov,
+        }
+    except Exception:
+        return None
+
+
+# ── StaticPressure / StaticTemperature ───────────────────────────────────────
+
+def parse_static_pressure(msg: Any) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.equipment.air_data.StaticPressure message.
+
+    Returns
+    -------
+    dict with keys:
+        pressure_pa       float  Pascals
+        pressure_variance float  Pa²
+    """
+    if msg is None:
+        return None
+    try:
+        return {
+            "pressure_pa":       float(_getf(msg, "static_pressure",          default=0.0)),
+            "pressure_variance": float(_getf(msg, "static_pressure_variance", default=0.0)),
+        }
+    except Exception:
+        return None
+
+
+def parse_static_temperature(msg: Any) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.equipment.air_data.StaticTemperature message.
+
+    Returns
+    -------
+    dict with keys:
+        temperature_k float  Kelvin
+    """
+    if msg is None:
+        return None
+    try:
+        return {
+            "temperature_k": float(_getf(msg, "static_temperature", default=273.15)),
+        }
+    except Exception:
+        return None
+
+
+# ── NodeStatus ────────────────────────────────────────────────────────────────
+
+def parse_node_status(msg: Any, source_node_id: int) -> Optional[Dict[str, Any]]:
+    """Parse a uavcan.protocol.NodeStatus message.
+
+    Returns
+    -------
+    dict with keys:
+        node_id        int
+        uptime_sec     int
+        health         int  0=OK .. 3=CRITICAL
+        health_label   str
+        mode           int
+        mode_label     str
+        vendor_code    int
+    """
+    if msg is None:
+        return None
+    try:
+        health      = int(_getf(msg, "health",                        default=0))
+        mode        = int(_getf(msg, "mode",                          default=0))
+        uptime      = int(_getf(msg, "uptime_sec",                    default=0))
+        vendor_code = int(_getf(msg, "vendor_specific_status_code",   default=0))
+        return {
+            "node_id":      source_node_id,
+            "uptime_sec":   uptime,
+            "health":       health,
+            "health_label": HEALTH_LABEL.get(health, f"UNKNOWN({health})"),
+            "mode":         mode,
+            "mode_label":   MODE_LABEL.get(mode, f"UNKNOWN({mode})"),
+            "vendor_code":  vendor_code,
+        }
+    except Exception:
+        return None
+
+
+# ── RTCM stream chunking ──────────────────────────────────────────────────────
+
+def chunk_rtcm(data: bytes, sequence_id: int) -> List[Dict[str, Any]]:
+    """Split a raw RTCM byte string into DroneCAN RTCMStream message dicts.
+
+    Each chunk carries up to RTCM_MAX_CHUNK bytes.  The caller must convert
+    these dicts into actual dronecan.uavcan.equipment.gnss.RTCMStream objects
+    and broadcast them on the bus.
+
+    Parameters
+    ----------
+    data        : raw RTCM correction bytes
+    sequence_id : monotonically increasing counter (uint16, wraps at 65535)
+
+    Returns
+    -------
+    List of dicts:  {"sequence_id": int, "data": bytes}
+    """
+    chunks = []
+    for i in range(0, len(data), RTCM_MAX_CHUNK):
+        chunks.append({
+            "sequence_id": sequence_id & 0xFFFF,
+            "data": data[i:i + RTCM_MAX_CHUNK],
+        })
+        sequence_id += 1
+    return chunks

jetson/ros2_ws/src/saltybot_dronecan_gps/saltybot_dronecan_gps/here4_node.py

@@ -0,0 +1,532 @@
+"""here4_node.py — ROS2 node for Here4 GPS via DroneCAN/UAVCAN v0 on CANable2.
+
+bd-p47c: CANable2 (freed from ESP32 BALANCE comms by bd-wim1) is now used
+for Here4 GPS at 1 Mbps DroneCAN.
+
+CAN setup (run once before launching, or use bring_up_can:=true arg)
+-----------------------------------------------------------------------
+  sudo ip link set can0 down
+  sudo ip link set can0 type can bitrate 1000000
+  sudo ip link set can0 up
+
+DroneCAN messages received from Here4
+--------------------------------------
+  uavcan.equipment.gnss.Fix2                 DTID 1063   ~5 Hz
+  uavcan.equipment.gnss.Auxiliary            DTID 1060   ~5 Hz
+  uavcan.equipment.ahrs.RawIMU               DTID 1003  ~50 Hz
+  uavcan.equipment.ahrs.MagneticFieldStrength2 DTID 1001 ~10 Hz
+  uavcan.equipment.air_data.StaticPressure   DTID 1028  ~10 Hz
+  uavcan.equipment.air_data.StaticTemperature DTID 1029  ~10 Hz
+  uavcan.protocol.NodeStatus                 DTID 341    ~1 Hz
+
+DroneCAN messages transmitted to Here4
+----------------------------------------
+  uavcan.equipment.gnss.RTCMStream           DTID 1062   on /rtcm input
+
+ROS2 topics published
+----------------------
+  /gps/fix              sensor_msgs/NavSatFix     5 Hz — feeds navsat_transform_node
+  /gps/velocity         geometry_msgs/TwistWithCovarianceStamped  5 Hz
+  /here4/fix            sensor_msgs/NavSatFix     alias of /gps/fix
+  /here4/imu            sensor_msgs/Imu          50 Hz
+  /here4/mag            sensor_msgs/MagneticField 10 Hz
+  /here4/baro           sensor_msgs/FluidPressure 10 Hz
+  /here4/status         std_msgs/String JSON       1 Hz (node ID, health, fix quality)
+  /here4/node_id        std_msgs/Int32             node ID once discovered
+
+ROS2 topics subscribed
+-----------------------
+  /rtcm                 std_msgs/ByteMultiArray   — RTCM corrections (from NTRIP client)
+                        or std_msgs/String (hex-encoded, fallback)
+
+Parameters
+----------
+  can_interface        str    SocketCAN interface name        default: can0
+  local_node_id        int    This node's DroneCAN ID (1-127) default: 126
+  bitrate              int    CAN bitrate, bps               default: 1000000
+  bring_up_can         bool   Bring up can_interface via ip   default: false
+  node_id_filter       int    Specific Here4 node ID (0=auto) default: 0
+  fix_frame_id         str    Frame ID for NavSatFix          default: gps
+  imu_frame_id         str    Frame ID for Imu                default: here4_imu
+"""
+
+from __future__ import annotations
+
+import json
+import math
+import subprocess
+import threading
+import time
+from typing import Any, Optional
+
+import rclpy
+from rclpy.node import Node
+from geometry_msgs.msg import TwistWithCovarianceStamped
+from sensor_msgs.msg import FluidPressure, Imu, MagneticField, NavSatFix, NavSatStatus
+from std_msgs.msg import ByteMultiArray, Int32, String
+
+from .dronecan_parser import (
+    FIX_3D,
+    FIX_NO_FIX,
+    chunk_rtcm,
+    parse_fix2,
+    parse_mag,
+    parse_raw_imu,
+    parse_static_pressure,
+    parse_static_temperature,
+    parse_node_status,
+)
+
+# Gauss → Tesla conversion
+_GA_TO_T = 1e-4
+
+# NavSatStatus mapping from DroneCAN fix type
+_FIX_TO_NAV_STATUS = {
+    0: NavSatStatus.STATUS_NO_FIX,   # NO_FIX
+    1: NavSatStatus.STATUS_NO_FIX,   # TIME_ONLY
+    2: NavSatStatus.STATUS_FIX,      # 2D_FIX
+    3: NavSatStatus.STATUS_FIX,      # 3D_FIX  (upgraded to SBAS/RTK when applicable)
+}
+
+# Here4 supports GPS+GLONASS+BeiDou+Galileo
+_SERVICE_FLAGS = (NavSatStatus.SERVICE_GPS | NavSatStatus.SERVICE_GLONASS |
+                  NavSatStatus.SERVICE_GALILEO | NavSatStatus.SERVICE_COMPASS)
+
+# RTCM injection sequence counter (per-session, wraps at 65535)
+_rtcm_seq = 0
+_rtcm_lock = threading.Lock()
+
+
+def _bring_up_can(iface: str, bitrate: int, logger) -> bool:
+    """Bring up the SocketCAN interface at the requested bitrate."""
+    try:
+        subprocess.run(["ip", "link", "set", iface, "down"],          check=False)
+        subprocess.run(["ip", "link", "set", iface, "type", "can",
+                        "bitrate", str(bitrate)],                      check=True)
+        subprocess.run(["ip", "link", "set", iface, "up"],             check=True)
+        logger.info(f"SocketCAN {iface} up at {bitrate} bps")
+        return True
+    except subprocess.CalledProcessError as exc:
+        logger.error(f"Failed to bring up {iface}: {exc} — check sudo/udev rules")
+        return False
+
+
+class Here4CanNode(Node):
+    """DroneCAN bridge publishing Here4 GPS, IMU, mag, and baro to ROS2."""
+
+    def __init__(self) -> None:
+        super().__init__("here4_can_node")
+
+        # ── Parameters ────────────────────────────────────────────────────
+        self.declare_parameter("can_interface",    "can0")
+        self.declare_parameter("local_node_id",    126)
+        self.declare_parameter("bitrate",          1_000_000)
+        self.declare_parameter("bring_up_can",     False)
+        self.declare_parameter("node_id_filter",   0)       # 0 = auto-detect
+        self.declare_parameter("fix_frame_id",     "gps")
+        self.declare_parameter("imu_frame_id",     "here4_imu")
+
+        self._iface        = self.get_parameter("can_interface").value
+        self._local_nid    = self.get_parameter("local_node_id").value
+        self._bitrate      = self.get_parameter("bitrate").value
+        self._bring_up     = self.get_parameter("bring_up_can").value
+        self._nid_filter   = self.get_parameter("node_id_filter").value
+        self._fix_frame    = self.get_parameter("fix_frame_id").value
+        self._imu_frame    = self.get_parameter("imu_frame_id").value
+
+        # ── State ─────────────────────────────────────────────────────────
+        self._here4_nid: Optional[int] = self._nid_filter if self._nid_filter else None
+        self._last_fix: Optional[dict] = None
+        self._last_temp_k: float = 293.15   # 20 °C default until first reading
+        self._dc_node = None                # dronecan node, set up after CAN is ready
+
+        # ── Publishers ────────────────────────────────────────────────────
+        self._pub_fix     = self.create_publisher(NavSatFix,
+                                "/gps/fix",       10)
+        self._pub_fix_h4  = self.create_publisher(NavSatFix,
+                                "/here4/fix",     10)
+        self._pub_vel     = self.create_publisher(TwistWithCovarianceStamped,
+                                "/gps/velocity",  10)
+        self._pub_imu     = self.create_publisher(Imu,
+                                "/here4/imu",     10)
+        self._pub_mag     = self.create_publisher(MagneticField,
+                                "/here4/mag",     10)
+        self._pub_baro    = self.create_publisher(FluidPressure,
+                                "/here4/baro",    10)
+        self._pub_status  = self.create_publisher(String,
+                                "/here4/status",  10)
+        self._pub_node_id = self.create_publisher(Int32,
+                                "/here4/node_id", 10)
+
+        # ── Subscriptions ─────────────────────────────────────────────────
+        self.create_subscription(ByteMultiArray, "/rtcm",
+                                 self._on_rtcm_bytes, 10)
+        self.create_subscription(String, "/rtcm_hex",
+                                 self._on_rtcm_hex, 10)
+
+        # ── Bring up CAN if requested ─────────────────────────────────────
+        if self._bring_up:
+            _bring_up_can(self._iface, self._bitrate, self.get_logger())
+
+        # ── Initialise DroneCAN node ──────────────────────────────────────
+        self._init_dronecan()
+
+        # ── Timers ────────────────────────────────────────────────────────
+        # Poll DroneCAN at 200 Hz (5 ms) to drain the RX queue in real-time
+        self.create_timer(0.005, self._spin_dronecan)
+        # Status publish at 1 Hz
+        self.create_timer(1.0,   self._publish_status)
+
+    # ── DroneCAN initialisation ───────────────────────────────────────────
+
+    def _init_dronecan(self) -> None:
+        try:
+            import dronecan  # type: ignore[import]
+        except ImportError:
+            self.get_logger().error(
+                "dronecan package not found — install with: pip install dronecan\n"
+                "Here4 node will not receive GPS data until dronecan is installed."
+            )
+            return
+
+        try:
+            self._dc_node = dronecan.make_node(
+                f"socketcan:{self._iface}",
+                node_id=self._local_nid,
+                bitrate=self._bitrate,
+            )
+        except Exception as exc:
+            self.get_logger().error(
+                f"Failed to open DroneCAN on {self._iface}: {exc}\n"
+                f"Verify: ip link show {self._iface}  and try bring_up_can:=true"
+            )
+            return
+
+        # ── Register message handlers ──────────────────────────────────────
+        dc = dronecan
+        self._dc_node.add_handler(dc.uavcan.equipment.gnss.Fix2,
+                                  self._on_fix2)
+        self._dc_node.add_handler(dc.uavcan.equipment.ahrs.RawIMU,
+                                  self._on_raw_imu)
+        self._dc_node.add_handler(dc.uavcan.equipment.ahrs.MagneticFieldStrength2,
+                                  self._on_mag)
+        self._dc_node.add_handler(dc.uavcan.equipment.air_data.StaticPressure,
+                                  self._on_pressure)
+        self._dc_node.add_handler(dc.uavcan.equipment.air_data.StaticTemperature,
+                                  self._on_temperature)
+        self._dc_node.add_handler(dc.uavcan.protocol.NodeStatus,
+                                  self._on_node_status)
+
+        self.get_logger().info(
+            f"DroneCAN node ready: {self._iface} @ {self._bitrate} bps "
+            f"local_id={self._local_nid}"
+        )
+
+    # ── DroneCAN spin (called from 5 ms timer) ────────────────────────────
+
+    def _spin_dronecan(self) -> None:
+        if self._dc_node is None:
+            return
+        try:
+            self._dc_node.spin(timeout=0)
+        except Exception as exc:
+            self.get_logger().warning(
+                f"DroneCAN spin error: {exc}",
+                throttle_duration_sec=5.0,
+            )
+
+    # ── Source node filter ────────────────────────────────────────────────
+
+    def _accept(self, event: Any) -> bool:  # type: ignore[valid-type]
+        """Return True if this event comes from the tracked Here4 node."""
+        src = getattr(getattr(event, "transfer", None), "source_node_id", None)
+        if src is None:
+            return True  # unknown source — accept
+        if self._here4_nid is None:
+            return True  # auto-detect mode — accept any
+        return src == self._here4_nid
+
+    # ── DroneCAN message handlers ─────────────────────────────────────────
+
+    def _on_fix2(self, event) -> None:
+        src = getattr(getattr(event, "transfer", None), "source_node_id", None)
+
+        # Auto-latch: first node that sends Fix2 becomes our Here4
+        if self._here4_nid is None and src is not None:
+            self._here4_nid = src
+            self.get_logger().info(
+                f"Here4 auto-discovered: DroneCAN node ID {src}"
+            )
+            nid_msg = Int32()
+            nid_msg.data = src
+            self._pub_node_id.publish(nid_msg)
+
+        if not self._accept(event):
+            return
+        d = parse_fix2(event.message)
+        if d is None:
+            return
+        self._last_fix = d
+        stamp = self.get_clock().now().to_msg()
+        self._publish_navsatfix(d, stamp)
+        self._publish_velocity(d, stamp)
+
+    def _on_raw_imu(self, event) -> None:
+        if not self._accept(event):
+            return
+        d = parse_raw_imu(event.message)
+        if d is None:
+            return
+        stamp = self.get_clock().now().to_msg()
+        msg = Imu()
+        msg.header.stamp    = stamp
+        msg.header.frame_id = self._imu_frame
+
+        # Orientation: not provided by DroneCAN RawIMU — signal unknown
+        msg.orientation_covariance[0] = -1.0
+
+        gx, gy, gz = d["gyro_xyz"]
+        msg.angular_velocity.x = gx
+        msg.angular_velocity.y = gy
+        msg.angular_velocity.z = gz
+        _fill_cov9(msg.angular_velocity_covariance, d["gyro_cov"])
+
+        ax, ay, az = d["accel_xyz"]
+        msg.linear_acceleration.x = ax
+        msg.linear_acceleration.y = ay
+        msg.linear_acceleration.z = az
+        _fill_cov9(msg.linear_acceleration_covariance, d["accel_cov"])
+
+        self._pub_imu.publish(msg)
+
+    def _on_mag(self, event) -> None:
+        if not self._accept(event):
+            return
+        d = parse_mag(event.message)
+        if d is None:
+            return
+        stamp = self.get_clock().now().to_msg()
+        msg = MagneticField()
+        msg.header.stamp    = stamp
+        msg.header.frame_id = self._imu_frame
+        gx, gy, gz = d["field_ga"]
+        msg.magnetic_field.x = gx * _GA_TO_T
+        msg.magnetic_field.y = gy * _GA_TO_T
+        msg.magnetic_field.z = gz * _GA_TO_T
+        _fill_cov9(msg.magnetic_field_covariance,
+                   [v * _GA_TO_T * _GA_TO_T for v in d["field_cov"]])
+        self._pub_mag.publish(msg)
+
+    def _on_pressure(self, event) -> None:
+        if not self._accept(event):
+            return
+        d = parse_static_pressure(event.message)
+        if d is None:
+            return
+        stamp = self.get_clock().now().to_msg()
+        msg = FluidPressure()
+        msg.header.stamp    = stamp
+        msg.header.frame_id = self._imu_frame
+        msg.fluid_pressure  = d["pressure_pa"]
+        msg.variance        = d["pressure_variance"]
+        self._pub_baro.publish(msg)
+
+    def _on_temperature(self, event) -> None:
+        if not self._accept(event):
+            return
+        d = parse_static_temperature(event.message)
+        if d is None:
+            return
+        self._last_temp_k = d["temperature_k"]
+
+    def _on_node_status(self, event) -> None:
+        src = getattr(getattr(event, "transfer", None), "source_node_id", None)
+        if src is None:
+            return
+        d = parse_node_status(event.message, src)
+        if d is None:
+            return
+
+        # Auto-discovery: latch first node that sends GPS-relevant data
+        # NodeStatus alone is not enough — we track whichever source_node_id
+        # first delivered a Fix2 message; if none yet, log all nodes seen.
+        if self._here4_nid is None:
+            # Any node could be Here4 — we'll latch on first Fix2 source
+            self.get_logger().debug(
+                f"DroneCAN node {src} alive: health={d['health_label']} "
+                f"mode={d['mode_label']} uptime={d['uptime_sec']}s"
+            )
+        elif src == self._here4_nid:
+            self._last_node_status = d
+
+    # ── NavSatFix publishing ─────────────────────────────────────────────
+
+    def _publish_navsatfix(self, d: dict, stamp) -> None:
+        fix_type = d["fix_type"]
+
+        status = NavSatStatus()
+        status.service = _SERVICE_FLAGS
+
+        # Upgrade status for RTK: hdop < 0.5 and 3D fix → treat as SBAS/RTK
+        if fix_type == FIX_3D:
+            if d["hdop"] < 0.5:
+                status.status = NavSatStatus.STATUS_GBAS_FIX   # RTK fixed
+            elif d["hdop"] < 1.5:
+                status.status = NavSatStatus.STATUS_SBAS_FIX   # SBAS/DGPS
+            else:
+                status.status = NavSatStatus.STATUS_FIX
+        else:
+            status.status = _FIX_TO_NAV_STATUS.get(fix_type, NavSatStatus.STATUS_NO_FIX)
+
+        msg = NavSatFix()
+        msg.header.stamp    = stamp
+        msg.header.frame_id = self._fix_frame
+        msg.status          = status
+        msg.latitude        = d["lat_deg"]
+        msg.longitude       = d["lon_deg"]
+        msg.altitude        = d["alt_msl_m"]
+
+        # Position covariance (diagonal from DroneCAN; full matrix if available)
+        pos_cov = d["pos_cov"]
+        msg.position_covariance_type = (
+            NavSatFix.COVARIANCE_TYPE_FULL if any(pos_cov) else
+            NavSatFix.COVARIANCE_TYPE_APPROXIMATED
+        )
+        if any(pos_cov):
+            for i, v in enumerate(pos_cov):
+                msg.position_covariance[i] = v
+        else:
+            # Approximate from HDOP/VDOP: σ_h ≈ hdop × 3m, σ_v ≈ vdop × 5m
+            sh2 = (d["hdop"] * 3.0) ** 2
+            sv2 = (d["vdop"] * 5.0) ** 2
+            msg.position_covariance[0] = sh2   # east
+            msg.position_covariance[4] = sh2   # north
+            msg.position_covariance[8] = sv2   # up
+
+        self._pub_fix.publish(msg)
+        self._pub_fix_h4.publish(msg)
+
+    def _publish_velocity(self, d: dict, stamp) -> None:
+        vn, ve, vd = d["ned_vel"]
+        msg = TwistWithCovarianceStamped()
+        msg.header.stamp    = stamp
+        msg.header.frame_id = self._fix_frame
+        # NED → ENU: x=east=ve, y=north=vn, z=up=-vd
+        msg.twist.twist.linear.x = ve
+        msg.twist.twist.linear.y = vn
+        msg.twist.twist.linear.z = -vd
+        # Velocity covariance: approximate from HDOP
+        vel_var = (d["hdop"] * 0.2) ** 2
+        msg.twist.covariance[0]  = vel_var   # xx (east)
+        msg.twist.covariance[7]  = vel_var   # yy (north)
+        msg.twist.covariance[14] = (d["vdop"] * 0.3) ** 2  # zz (up)
+        self._pub_vel.publish(msg)
+
+    # ── Status publish (1 Hz) ────────────────────────────────────────────
+
+    def _publish_status(self) -> None:
+        fix = self._last_fix
+        ns = getattr(self, "_last_node_status", None)
+
+        payload: dict = {
+            "here4_node_id":  self._here4_nid,
+            "can_interface":  self._iface,
+            "dc_node_ready":  self._dc_node is not None,
+            "fix_type":       fix["fix_type"]    if fix else FIX_NO_FIX,
+            "fix_label":      fix["fix_label"]   if fix else "NO_FIX",
+            "sats_used":      fix["sats_used"]   if fix else 0,
+            "hdop":           round(fix["hdop"], 2) if fix else 99.0,
+            "lat_deg":        round(fix["lat_deg"],    7) if fix else 0.0,
+            "lon_deg":        round(fix["lon_deg"],    7) if fix else 0.0,
+            "alt_msl_m":      round(fix["alt_msl_m"],  2) if fix else 0.0,
+            "temp_c":         round(self._last_temp_k - 273.15, 1),
+            "node_health":    ns["health_label"] if ns else "UNKNOWN",
+            "node_uptime_s":  ns["uptime_sec"]   if ns else 0,
+        }
+        msg = String()
+        msg.data = json.dumps(payload)
+        self._pub_status.publish(msg)
+
+        # Also publish discovered node ID
+        if self._here4_nid is not None:
+            nid_msg = Int32()
+            nid_msg.data = self._here4_nid
+            self._pub_node_id.publish(nid_msg)
+
+    # ── RTCM injection ────────────────────────────────────────────────────
+
+    def _on_rtcm_bytes(self, msg: ByteMultiArray) -> None:
+        """Receive RTCM bytes from /rtcm and inject via DroneCAN RTCMStream."""
+        raw = bytes(msg.data)
+        self._inject_rtcm(raw)
+
+    def _on_rtcm_hex(self, msg: String) -> None:
+        """Receive hex-encoded RTCM from /rtcm_hex (fallback topic)."""
+        try:
+            raw = bytes.fromhex(msg.data.strip())
+        except ValueError as exc:
+            self.get_logger().error(f"Bad /rtcm_hex: {exc}")
+            return
+        self._inject_rtcm(raw)
+
+    def _inject_rtcm(self, raw: bytes) -> None:
+        if self._dc_node is None or not raw:
+            return
+
+        global _rtcm_seq
+        try:
+            import dronecan  # type: ignore[import]
+        except ImportError:
+            return
+
+        with _rtcm_lock:
+            chunks = chunk_rtcm(raw, _rtcm_seq)
+            _rtcm_seq = (_rtcm_seq + len(chunks)) & 0xFFFF
+
+        for chunk in chunks:
+            try:
+                rtcm_msg = dronecan.uavcan.equipment.gnss.RTCMStream()
+                rtcm_msg.sequence_id = chunk["sequence_id"]
+                rtcm_msg.data = list(chunk["data"])
+                self._dc_node.broadcast(rtcm_msg)
+            except Exception as exc:
+                self.get_logger().warning(
+                    f"RTCM inject error (seq {chunk['sequence_id']}): {exc}",
+                    throttle_duration_sec=2.0,
+                )
+
+    # ── Shutdown ──────────────────────────────────────────────────────────
+
+    def destroy_node(self) -> None:
+        if self._dc_node is not None:
+            try:
+                self._dc_node.close()
+            except Exception:
+                pass
+        super().destroy_node()
+
+
+# ── Covariance helper ─────────────────────────────────────────────────────────
+
+def _fill_cov9(ros_cov, values) -> None:
+    """Fill a 9-element ROS2 covariance array from a list."""
+    for i, v in enumerate(values[:9]):
+        ros_cov[i] = float(v)
+
+
+# ── Entry point ───────────────────────────────────────────────────────────────
+
+def main(args=None) -> None:
+    rclpy.init(args=args)
+    node = Here4CanNode()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        node.destroy_node()
+        rclpy.shutdown()
+
+
+if __name__ == "__main__":
+    main()

jetson/ros2_ws/src/saltybot_dronecan_gps/setup.cfg

@@ -0,0 +1,5 @@
+[develop]
+script_dir=$base/lib/saltybot_dronecan_gps
+
+[install]
+install_scripts=$base/lib/saltybot_dronecan_gps

jetson/ros2_ws/src/saltybot_dronecan_gps/setup.py

@@ -0,0 +1,27 @@
+from setuptools import setup
+
+package_name = "saltybot_dronecan_gps"
+
+setup(
+    name=package_name,
+    version="0.1.0",
+    packages=[package_name],
+    data_files=[
+        ("share/ament_index/resource_index/packages", [f"resource/{package_name}"]),
+        (f"share/{package_name}", ["package.xml"]),
+        (f"share/{package_name}/config", ["config/here4_params.yaml"]),
+        (f"share/{package_name}/launch", ["launch/here4.launch.py"]),
+    ],
+    install_requires=["setuptools"],
+    zip_safe=True,
+    maintainer="sl-perception",
+    maintainer_email="sl-perception@saltylab.local",
+    description="DroneCAN/UAVCAN v0 bridge for Here4 GPS via CANable2 (bd-p47c)",
+    license="MIT",
+    tests_require=["pytest"],
+    entry_points={
+        "console_scripts": [
+            "here4_node = saltybot_dronecan_gps.here4_node:main",
+        ],
+    },
+)

jetson/ros2_ws/src/saltybot_dronecan_gps/test/test_dronecan_parser.py

@@ -0,0 +1,367 @@
+#!/usr/bin/env python3
+"""Unit tests for saltybot_dronecan_gps.dronecan_parser.
+
+No dronecan library, ROS2, or CAN hardware required.
+Uses simple Python objects (namespaces) to simulate dronecan message objects.
+
+Run with:  pytest test/ -v
+"""
+
+import math
+import types
+import unittest
+
+from saltybot_dronecan_gps.dronecan_parser import (
+    DTID_FIX2,
+    DTID_RAW_IMU,
+    DTID_MAG_FIELD,
+    DTID_STATIC_PRESSURE,
+    DTID_STATIC_TEMPERATURE,
+    DTID_NODE_STATUS,
+    DTID_RTCM_STREAM,
+    FIX_NO_FIX,
+    FIX_TIME_ONLY,
+    FIX_2D,
+    FIX_3D,
+    RTCM_MAX_CHUNK,
+    chunk_rtcm,
+    parse_fix2,
+    parse_mag,
+    parse_node_status,
+    parse_raw_imu,
+    parse_static_pressure,
+    parse_static_temperature,
+    _getf,
+    _list3,
+    _list9,
+)
+
+
+# ── Helpers ───────────────────────────────────────────────────────────────────
+
+def _ns(**kwargs) -> types.SimpleNamespace:
+    """Build a simple namespace to mimic a dronecan message object."""
+    return types.SimpleNamespace(**kwargs)
+
+
+def _ns_vec(*values):
+    """Return an object that is indexable like a dronecan vector field."""
+    return list(values)
+
+
+# ── DTID constants ────────────────────────────────────────────────────────────
+
+class TestDtidConstants(unittest.TestCase):
+    def test_known_values(self):
+        self.assertEqual(DTID_FIX2,               1063)
+        self.assertEqual(DTID_RAW_IMU,             1003)
+        self.assertEqual(DTID_MAG_FIELD,           1001)
+        self.assertEqual(DTID_STATIC_PRESSURE,     1028)
+        self.assertEqual(DTID_STATIC_TEMPERATURE,  1029)
+        self.assertEqual(DTID_NODE_STATUS,          341)
+        self.assertEqual(DTID_RTCM_STREAM,         1062)
+
+    def test_rtcm_chunk_size(self):
+        self.assertEqual(RTCM_MAX_CHUNK, 128)
+
+
+# ── _getf / _list3 / _list9 ──────────────────────────────────────────────────
+
+class TestHelpers(unittest.TestCase):
+    def test_getf_simple(self):
+        obj = _ns(x=42)
+        self.assertEqual(_getf(obj, "x"), 42)
+
+    def test_getf_missing(self):
+        obj = _ns(x=1)
+        self.assertIsNone(_getf(obj, "y"))
+
+    def test_getf_default(self):
+        obj = _ns()
+        self.assertEqual(_getf(obj, "missing", default=99), 99)
+
+    def test_list3_ok(self):
+        self.assertEqual(_list3([1.0, 2.0, 3.0]), [1.0, 2.0, 3.0])
+
+    def test_list3_bad(self):
+        self.assertEqual(_list3(None), [0.0, 0.0, 0.0])
+
+    def test_list9_ok(self):
+        vals = list(range(9))
+        self.assertEqual(_list9(vals), [float(v) for v in vals])
+
+    def test_list9_short(self):
+        self.assertEqual(_list9(None), [0.0] * 9)
+
+
+# ── parse_fix2 ────────────────────────────────────────────────────────────────
+
+class TestParseFix2(unittest.TestCase):
+
+    def _make_fix(self, lat_1e8=0, lon_1e8=0, alt_msl_mm=0, alt_ell_mm=0,
+                  ned_vel=None, status=FIX_3D, sats=12,
+                  pdop=1.2, hdop=0.9, vdop=1.5,
+                  pos_cov=None, undulation=5.0, gnss_ts=0):
+        return _ns(
+            latitude_deg_1e8  = lat_1e8,
+            longitude_deg_1e8 = lon_1e8,
+            height_msl_mm     = alt_msl_mm,
+            height_ellipsoid_mm = alt_ell_mm,
+            ned_velocity      = ned_vel if ned_vel is not None else _ns_vec(0.0, 0.0, 0.0),
+            status            = status,
+            sats_used         = sats,
+            pdop              = pdop,
+            hdop              = hdop,
+            vdop              = vdop,
+            position_covariance = pos_cov,
+            undulation        = undulation,
+            gnss_timestamp    = gnss_ts,
+        )
+
+    def test_basic_3d_fix(self):
+        msg = self._make_fix(
+            lat_1e8    = 4_576_543_210,  # 45.7654321°
+            lon_1e8    = -7_345_678_901, # -73.45678901°
+            alt_msl_mm = 50_000,         # 50 m
+            alt_ell_mm = 52_000,         # 52 m
+            ned_vel    = _ns_vec(1.5, -0.3, 0.0),
+            sats       = 14,
+            hdop       = 0.8,
+        )
+        d = parse_fix2(msg)
+        self.assertIsNotNone(d)
+        self.assertAlmostEqual(d["lat_deg"],       45.7654321, places=5)
+        self.assertAlmostEqual(d["lon_deg"],       -73.45678901, places=5)
+        self.assertAlmostEqual(d["alt_msl_m"],     50.0, places=3)
+        self.assertAlmostEqual(d["alt_ellipsoid_m"], 52.0, places=3)
+        self.assertEqual(d["ned_vel"], [1.5, -0.3, 0.0])
+        self.assertEqual(d["fix_type"],  FIX_3D)
+        self.assertEqual(d["fix_label"], "3D_FIX")
+        self.assertEqual(d["sats_used"], 14)
+        self.assertAlmostEqual(d["hdop"], 0.8, places=5)
+
+    def test_no_fix(self):
+        msg = self._make_fix(status=FIX_NO_FIX, sats=0)
+        d = parse_fix2(msg)
+        self.assertIsNotNone(d)
+        self.assertEqual(d["fix_type"],  FIX_NO_FIX)
+        self.assertEqual(d["fix_label"], "NO_FIX")
+        self.assertEqual(d["sats_used"], 0)
+
+    def test_time_only(self):
+        msg = self._make_fix(status=FIX_TIME_ONLY)
+        d = parse_fix2(msg)
+        self.assertEqual(d["fix_label"], "TIME_ONLY")
+
+    def test_2d_fix(self):
+        msg = self._make_fix(status=FIX_2D)
+        d = parse_fix2(msg)
+        self.assertEqual(d["fix_label"], "2D_FIX")
+
+    def test_position_covariance(self):
+        cov = [float(i) for i in range(9)]
+        msg = self._make_fix(pos_cov=cov)
+        d = parse_fix2(msg)
+        self.assertEqual(d["pos_cov"], cov)
+
+    def test_no_covariance_returns_zeros(self):
+        msg = self._make_fix(pos_cov=None)
+        d = parse_fix2(msg)
+        self.assertEqual(d["pos_cov"], [0.0] * 9)
+
+    def test_zero_lat_lon(self):
+        msg = self._make_fix(lat_1e8=0, lon_1e8=0)
+        d = parse_fix2(msg)
+        self.assertAlmostEqual(d["lat_deg"], 0.0, places=8)
+        self.assertAlmostEqual(d["lon_deg"], 0.0, places=8)
+
+    def test_returns_none_on_bad_input(self):
+        self.assertIsNone(parse_fix2(None))
+
+    def test_gnss_timestamp(self):
+        msg = self._make_fix(gnss_ts=1_000_000_000)
+        d = parse_fix2(msg)
+        self.assertEqual(d["gnss_timestamp_us"], 1_000_000_000)
+
+
+# ── parse_raw_imu ─────────────────────────────────────────────────────────────
+
+class TestParseRawImu(unittest.TestCase):
+
+    def _make_imu(self, gyro=None, accel=None, dt=0.02,
+                  gyro_cov=None, accel_cov=None):
+        return _ns(
+            rate_gyro_latest         = gyro  if gyro  else _ns_vec(0.0, 0.0, 0.0),
+            accelerometer_latest     = accel if accel else _ns_vec(0.0, 0.0, 9.81),
+            integration_interval     = dt,
+            rate_gyro_covariance     = gyro_cov  if gyro_cov  else [0.0] * 9,
+            accelerometer_covariance = accel_cov if accel_cov else [0.0] * 9,
+        )
+
+    def test_basic(self):
+        msg = self._make_imu(
+            gyro  = _ns_vec(0.01, -0.02, 0.03),
+            accel = _ns_vec(0.1, -0.2, 9.8),
+            dt    = 0.02,
+        )
+        d = parse_raw_imu(msg)
+        self.assertIsNotNone(d)
+        self.assertEqual(d["gyro_xyz"],  [0.01, -0.02, 0.03])
+        self.assertEqual(d["accel_xyz"], [0.1, -0.2, 9.8])
+        self.assertAlmostEqual(d["dt_s"], 0.02)
+
+    def test_covariances_returned(self):
+        cov = [float(i * 0.001) for i in range(9)]
+        msg = self._make_imu(gyro_cov=cov, accel_cov=cov)
+        d = parse_raw_imu(msg)
+        self.assertEqual(d["gyro_cov"],  cov)
+        self.assertEqual(d["accel_cov"], cov)
+
+    def test_none_input(self):
+        self.assertIsNone(parse_raw_imu(None))
+
+
+# ── parse_mag ─────────────────────────────────────────────────────────────────
+
+class TestParseMag(unittest.TestCase):
+
+    def _make_mag(self, sensor_id=0, field=None, cov=None):
+        return _ns(
+            sensor_id              = sensor_id,
+            magnetic_field_ga      = field if field else _ns_vec(0.1, 0.2, -0.5),
+            magnetic_field_covariance = cov if cov else [0.0] * 9,
+        )
+
+    def test_basic(self):
+        msg = self._make_mag(sensor_id=1, field=_ns_vec(0.1, 0.2, -0.5))
+        d = parse_mag(msg)
+        self.assertIsNotNone(d)
+        self.assertEqual(d["sensor_id"],  1)
+        self.assertEqual(d["field_ga"],   [0.1, 0.2, -0.5])
+
+    def test_none_input(self):
+        self.assertIsNone(parse_mag(None))
+
+
+# ── parse_static_pressure ────────────────────────────────────────────────────
+
+class TestParseStaticPressure(unittest.TestCase):
+
+    def test_basic(self):
+        msg = _ns(static_pressure=101325.0, static_pressure_variance=100.0)
+        d = parse_static_pressure(msg)
+        self.assertIsNotNone(d)
+        self.assertAlmostEqual(d["pressure_pa"],       101325.0)
+        self.assertAlmostEqual(d["pressure_variance"], 100.0)
+
+    def test_none_input(self):
+        self.assertIsNone(parse_static_pressure(None))
+
+
+# ── parse_static_temperature ─────────────────────────────────────────────────
+
+class TestParseStaticTemperature(unittest.TestCase):
+
+    def test_celsius_to_kelvin(self):
+        msg = _ns(static_temperature=293.15)  # 20 °C
+        d = parse_static_temperature(msg)
+        self.assertIsNotNone(d)
+        self.assertAlmostEqual(d["temperature_k"], 293.15)
+
+    def test_none_input(self):
+        self.assertIsNone(parse_static_temperature(None))
+
+
+# ── parse_node_status ────────────────────────────────────────────────────────
+
+class TestParseNodeStatus(unittest.TestCase):
+
+    def _make_status(self, health=0, mode=0, uptime=120, vendor_code=0):
+        return _ns(
+            health                     = health,
+            mode                       = mode,
+            uptime_sec                 = uptime,
+            vendor_specific_status_code = vendor_code,
+        )
+
+    def test_ok_operational(self):
+        msg = self._make_status(health=0, mode=0, uptime=300)
+        d = parse_node_status(msg, source_node_id=10)
+        self.assertIsNotNone(d)
+        self.assertEqual(d["node_id"],     10)
+        self.assertEqual(d["health"],      0)
+        self.assertEqual(d["health_label"], "OK")
+        self.assertEqual(d["mode_label"],  "OPERATIONAL")
+        self.assertEqual(d["uptime_sec"],  300)
+
+    def test_error_state(self):
+        msg = self._make_status(health=2, mode=0)
+        d = parse_node_status(msg, source_node_id=5)
+        self.assertEqual(d["health_label"], "ERROR")
+
+    def test_critical_state(self):
+        msg = self._make_status(health=3)
+        d = parse_node_status(msg, 7)
+        self.assertEqual(d["health_label"], "CRITICAL")
+
+    def test_none_input(self):
+        self.assertIsNone(parse_node_status(None, 1))
+
+
+# ── chunk_rtcm ────────────────────────────────────────────────────────────────
+
+class TestChunkRtcm(unittest.TestCase):
+
+    def test_empty(self):
+        chunks = chunk_rtcm(b"", 0)
+        self.assertEqual(chunks, [])
+
+    def test_single_chunk(self):
+        data = bytes(range(64))
+        chunks = chunk_rtcm(data, 5)
+        self.assertEqual(len(chunks), 1)
+        self.assertEqual(chunks[0]["sequence_id"], 5)
+        self.assertEqual(chunks[0]["data"],        data)
+
+    def test_exact_chunk_boundary(self):
+        data = bytes(RTCM_MAX_CHUNK)
+        chunks = chunk_rtcm(data, 0)
+        self.assertEqual(len(chunks), 1)
+        self.assertEqual(len(chunks[0]["data"]), RTCM_MAX_CHUNK)
+
+    def test_two_chunks(self):
+        data = bytes(RTCM_MAX_CHUNK + 1)
+        chunks = chunk_rtcm(data, 0)
+        self.assertEqual(len(chunks), 2)
+        self.assertEqual(len(chunks[0]["data"]), RTCM_MAX_CHUNK)
+        self.assertEqual(len(chunks[1]["data"]), 1)
+
+    def test_sequence_id_increments(self):
+        data = bytes(RTCM_MAX_CHUNK * 3)
+        chunks = chunk_rtcm(data, 10)
+        for i, chunk in enumerate(chunks):
+            self.assertEqual(chunk["sequence_id"], 10 + i)
+
+    def test_sequence_id_wraps_at_16bit(self):
+        data = bytes(RTCM_MAX_CHUNK * 2)
+        chunks = chunk_rtcm(data, 0xFFFF)
+        self.assertEqual(chunks[0]["sequence_id"], 0xFFFF)
+        self.assertEqual(chunks[1]["sequence_id"], 0x0000)   # wraps
+
+    def test_data_round_trip(self):
+        original = bytes(range(200))
+        chunks = chunk_rtcm(original, 0)
+        reassembled = b"".join(c["data"] for c in chunks)
+        self.assertEqual(reassembled, original)
+
+    def test_large_message(self):
+        data = bytes(1024)
+        chunks = chunk_rtcm(data, 0)
+        total_bytes = sum(len(c["data"]) for c in chunks)
+        self.assertEqual(total_bytes, 1024)
+        for c in chunks:
+            self.assertLessEqual(len(c["data"]), RTCM_MAX_CHUNK)
+
+
+if __name__ == "__main__":
+    unittest.main()

jetson/ros2_ws/src/saltybot_esp32_serial/config/esp32_balance_params.yaml

@@ -0,0 +1,20 @@
+esp32_balance_node:
+  ros__parameters:
+    # USB-CDC serial port: CH343 chip, VID:PID 1a86:55d3
+    # Udev symlink set by jetson/docs/pinout.md udev rules
+    serial_port: /dev/esp32-balance
+    baud_rate: 460800
+
+    # /cmd_vel linear.x (m/s) → speed units sent to ESP32-S3 BALANCE
+    speed_scale: 1000.0
+    # /cmd_vel angular.z (rad/s) → steer units (negative = flip turn convention)
+    steer_scale: -500.0
+
+    # Safety: send CMD_DRIVE(0,0) if /cmd_vel silent for this many seconds
+    command_timeout_s: 0.5
+
+    # CMD_HEARTBEAT TX interval in seconds (ESP32-S3 watchdog fires at 500 ms)
+    heartbeat_period: 0.2
+
+    # Reconnect attempt interval when serial is lost
+    reconnect_delay: 2.0

jetson/ros2_ws/src/saltybot_esp32_serial/launch/esp32_balance.launch.py

@@ -0,0 +1,73 @@
+"""esp32_balance.launch.py — Launch the Orin↔ESP32-S3 BALANCE USB-serial bridge.
+
+bd-wim1: replaces can_bridge_node (CANable2/python-can) with USB-CDC serial.
+The freed CANable2 slot is used by Here4 GPS (bd-p47c).
+
+USB device
+----------
+  CH343 USB-CDC chip on ESP32-S3 BALANCE board
+  VID:PID  1a86:55d3
+  Symlink  /dev/esp32-balance  (via udev rule in jetson/docs/pinout.md)
+  Baud     460800
+
+Usage
+-----
+  # Default:
+  ros2 launch saltybot_esp32_serial esp32_balance.launch.py
+
+  # Override port (e.g. direct ACM path):
+  ros2 launch saltybot_esp32_serial esp32_balance.launch.py serial_port:=/dev/ttyACM0
+
+  # Custom velocity scales:
+  ros2 launch saltybot_esp32_serial esp32_balance.launch.py speed_scale:=800.0 steer_scale:=-400.0
+"""
+
+import os
+from ament_index_python.packages import get_package_share_directory
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
+from launch_ros.actions import Node
+
+
+def generate_launch_description() -> LaunchDescription:
+    pkg_share = get_package_share_directory("saltybot_esp32_serial")
+    params_file = os.path.join(pkg_share, "config", "esp32_balance_params.yaml")
+
+    serial_port_arg = DeclareLaunchArgument(
+        "serial_port",
+        default_value="/dev/esp32-balance",
+        description="USB-CDC serial port for ESP32-S3 BALANCE (CH343, 1a86:55d3)",
+    )
+    speed_scale_arg = DeclareLaunchArgument(
+        "speed_scale",
+        default_value="1000.0",
+        description="linear.x (m/s) → motor speed units",
+    )
+    steer_scale_arg = DeclareLaunchArgument(
+        "steer_scale",
+        default_value="-500.0",
+        description="angular.z (rad/s) → steer units",
+    )
+
+    node = Node(
+        package="saltybot_esp32_serial",
+        executable="esp32_balance_node",
+        name="esp32_balance_node",
+        output="screen",
+        parameters=[
+            params_file,
+            {
+                "serial_port": LaunchConfiguration("serial_port"),
+                "speed_scale": LaunchConfiguration("speed_scale"),
+                "steer_scale": LaunchConfiguration("steer_scale"),
+            },
+        ],
+    )
+
+    return LaunchDescription([
+        serial_port_arg,
+        speed_scale_arg,
+        steer_scale_arg,
+        node,
+    ])

jetson/ros2_ws/src/saltybot_esp32_serial/package.xml

@@ -0,0 +1,40 @@
+<?xml version="1.0"?>
+<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
+<package format="3">
+  <name>saltybot_esp32_serial</name>
+  <version>0.1.0</version>
+  <description>
+    UART/USB-CDC serial bridge for SaltyBot Orin — interfaces with the
+    ESP32-S3 BALANCE board (CH343, 1a86:55d3) using a binary framing protocol
+    [0xAA][LEN][TYPE][PAYLOAD][CRC8].  Replaces saltybot_can_bridge (CANable2)
+    to free the CAN bus for Here4 GPS (bd-p47c).
+
+    Publishes the same ROS2 topics as saltybot_can_bridge for backward compat:
+      /saltybot/attitude, /can/battery, /can/vesc/{left,right}/state,
+      /can/connection_status
+
+    System dependency: pyserial (apt: python3-serial  or  pip: pyserial)
+    Bead: bd-wim1  Counterpart firmware: bd-66hx (hal)
+  </description>
+  <maintainer email="sl-perception@saltylab.local">sl-perception</maintainer>
+  <license>MIT</license>
+
+  <exec_depend>rclpy</exec_depend>
+  <exec_depend>std_msgs</exec_depend>
+  <exec_depend>geometry_msgs</exec_depend>
+  <exec_depend>sensor_msgs</exec_depend>
+
+  <!-- pyserial: apt install python3-serial  or  pip install pyserial -->
+  <exec_depend>python3-serial</exec_depend>
+
+  <buildtool_depend>ament_python</buildtool_depend>
+
+  <test_depend>ament_copyright</test_depend>
+  <test_depend>ament_flake8</test_depend>
+  <test_depend>ament_pep257</test_depend>
+  <test_depend>python3-pytest</test_depend>
+
+  <export>
+    <build_type>ament_python</build_type>
+  </export>
+</package>

jetson/ros2_ws/src/saltybot_esp32_serial/saltybot_esp32_serial/__init__.py

@@ -0,0 +1 @@
+# saltybot_esp32_serial — UART/USB-CDC bridge for ESP32-S3 BALANCE (bd-wim1)

jetson/ros2_ws/src/saltybot_esp32_serial/saltybot_esp32_serial/esp32_balance_node.py

@@ -0,0 +1,369 @@
+"""esp32_balance_node.py — ROS2 bridge: Orin ↔ ESP32-S3 BALANCE via USB-CDC serial.
+
+bd-wim1: replaces saltybot_can_bridge (CANable2/python-can) with USB serial.
+The CANable2 is freed for Here4 GPS (bd-p47c).
+
+Physical connection
+-------------------
+  Device  : /dev/esp32-balance  (CH343 USB-CDC, VID:PID 1a86:55d3)
+  Baud    : 460800, 8N1
+  Protocol: [0xAA][LEN][TYPE][PAYLOAD][CRC8]  (see esp32_balance_protocol.py)
+
+Subscriptions
+-------------
+  /cmd_vel               geometry_msgs/Twist   → CMD_DRIVE (at up to 50 Hz)
+  /estop                 std_msgs/Bool         → CMD_ESTOP
+  /saltybot/arm          std_msgs/Bool         → CMD_ARM
+  /saltybot/pid_update   std_msgs/String JSON  → CMD_PID  {"kp":…,"ki":…,"kd":…}
+
+Publications
+------------
+  /saltybot/attitude        std_msgs/String JSON  pitch, motor_cmd, state, etc.
+  /saltybot/balance_state   std_msgs/String       same as /saltybot/attitude (alias)
+  /can/battery              sensor_msgs/BatteryState  from TELEM_STATUS.vbat_mv
+  /can/vesc/left/state      std_msgs/Float32MultiArray  [erpm, duty≡0, voltage_mv/1000, current_ma/1000]
+  /can/vesc/right/state     std_msgs/Float32MultiArray  same layout
+  /can/connection_status    std_msgs/String       "connected" | "disconnected"
+
+  NOTE: /can/* topic names are preserved for backward compatibility with
+        nodes that subscribed to saltybot_can_bridge outputs.
+
+Parameters
+----------
+  serial_port       str    USB-CDC port           default: /dev/esp32-balance
+  baud_rate         int    Baud rate              default: 460800
+  speed_scale       float  linear.x (m/s) → units default: 1000.0
+  steer_scale       float  angular.z (rad/s) → units  default: -500.0
+  command_timeout_s float  /cmd_vel watchdog      default: 0.5
+  heartbeat_period  float  CMD_HEARTBEAT interval default: 0.2
+  reconnect_delay   float  Retry interval, s      default: 2.0
+"""
+
+from __future__ import annotations
+
+import json
+import threading
+import time
+from typing import Optional
+
+import rclpy
+import serial
+from geometry_msgs.msg import Twist
+from rclpy.node import Node
+from sensor_msgs.msg import BatteryState
+from std_msgs.msg import Bool, Float32MultiArray, String
+
+from .esp32_balance_protocol import (
+    BAUD_RATE,
+    SERIAL_PORT_DEFAULT,
+    AckFrame,
+    BalanceState,
+    BALANCE_STATE_LABEL,
+    FrameParser,
+    NackFrame,
+    StatusFrame,
+    VescFrame,
+    encode_arm,
+    encode_drive,
+    encode_estop,
+    encode_heartbeat,
+    encode_pid,
+)
+
+_WATCHDOG_HZ: float = 20.0   # TX watchdog check rate
+
+
+class Esp32BalanceNode(Node):
+    """Serial bridge replacing CANable2 CAN comms with USB-CDC to ESP32-S3 BALANCE."""
+
+    def __init__(self) -> None:
+        super().__init__("esp32_balance_node")
+
+        # ── Parameters ────────────────────────────────────────────────────
+        self.declare_parameter("serial_port",       SERIAL_PORT_DEFAULT)
+        self.declare_parameter("baud_rate",         BAUD_RATE)
+        self.declare_parameter("speed_scale",       1000.0)
+        self.declare_parameter("steer_scale",       -500.0)
+        self.declare_parameter("command_timeout_s", 0.5)
+        self.declare_parameter("heartbeat_period",  0.2)
+        self.declare_parameter("reconnect_delay",   2.0)
+
+        self._port_name     = self.get_parameter("serial_port").value
+        self._baud          = self.get_parameter("baud_rate").value
+        self._speed_scale   = self.get_parameter("speed_scale").value
+        self._steer_scale   = self.get_parameter("steer_scale").value
+        self._cmd_timeout   = self.get_parameter("command_timeout_s").value
+        self._hb_period     = self.get_parameter("heartbeat_period").value
+        self._reconnect_delay = self.get_parameter("reconnect_delay").value
+
+        # ── State ─────────────────────────────────────────────────────────
+        self._ser: Optional[serial.Serial] = None
+        self._ser_lock     = threading.Lock()
+        self._parser       = FrameParser()
+        self._last_cmd_time = time.monotonic()
+        self._watchdog_sent = False
+
+        # ── Publishers ────────────────────────────────────────────────────
+        self._pub_attitude   = self.create_publisher(String,             "/saltybot/attitude",      10)
+        self._pub_balance    = self.create_publisher(String,             "/saltybot/balance_state", 10)
+        self._pub_battery    = self.create_publisher(BatteryState,       "/can/battery",            10)
+        self._pub_vesc_left  = self.create_publisher(Float32MultiArray,  "/can/vesc/left/state",    10)
+        self._pub_vesc_right = self.create_publisher(Float32MultiArray,  "/can/vesc/right/state",   10)
+        self._pub_status     = self.create_publisher(String,             "/can/connection_status",  10)
+
+        # ── Subscriptions ─────────────────────────────────────────────────
+        self.create_subscription(Twist,  "/cmd_vel",            self._cmd_vel_cb,  10)
+        self.create_subscription(Bool,   "/estop",              self._estop_cb,    10)
+        self.create_subscription(Bool,   "/saltybot/arm",       self._arm_cb,      10)
+        self.create_subscription(String, "/saltybot/pid_update", self._pid_cb,     10)
+
+        # ── Timers ────────────────────────────────────────────────────────
+        self.create_timer(self._hb_period,     self._heartbeat_cb)
+        self.create_timer(1.0 / _WATCHDOG_HZ,  self._watchdog_cb)
+        self.create_timer(self._reconnect_delay, self._reconnect_cb)
+
+        # ── Open port + start reader thread ───────────────────────────────
+        self._try_connect()
+        self._reader_thread = threading.Thread(
+            target=self._reader_loop, daemon=True, name="balance_serial_reader"
+        )
+        self._reader_thread.start()
+
+        self.get_logger().info(
+            f"esp32_balance_node — {self._port_name} @ {self._baud} baud | "
+            f"speed_scale={self._speed_scale} steer_scale={self._steer_scale}"
+        )
+
+    # ── Serial management ─────────────────────────────────────────────────
+
+    def _try_connect(self) -> None:
+        with self._ser_lock:
+            if self._ser is not None and self._ser.is_open:
+                return
+            try:
+                self._ser = serial.Serial(
+                    port=self._port_name,
+                    baudrate=self._baud,
+                    timeout=0.05,
+                    write_timeout=0.1,
+                )
+                self._ser.reset_input_buffer()
+                self._parser.reset()
+                self.get_logger().info(f"Serial open: {self._port_name}")
+                self._publish_status("connected")
+            except serial.SerialException as exc:
+                self.get_logger().warning(
+                    f"Cannot open {self._port_name}: {exc} — retry in {self._reconnect_delay:.0f} s",
+                    throttle_duration_sec=self._reconnect_delay,
+                )
+                self._ser = None
+                self._publish_status("disconnected")
+
+    def _reconnect_cb(self) -> None:
+        with self._ser_lock:
+            open_ok = self._ser is not None and self._ser.is_open
+        if not open_ok:
+            self._try_connect()
+
+    def _handle_serial_error(self, exc: Exception, context: str) -> None:
+        self.get_logger().warning(f"Serial error in {context}: {exc}")
+        with self._ser_lock:
+            if self._ser is not None:
+                try:
+                    self._ser.close()
+                except Exception:
+                    pass
+            self._ser = None
+        self._publish_status("disconnected")
+
+    # ── Serial write helper ───────────────────────────────────────────────
+
+    def _write(self, data: bytes, context: str = "") -> bool:
+        with self._ser_lock:
+            if self._ser is None or not self._ser.is_open:
+                return False
+            ser = self._ser
+        try:
+            ser.write(data)
+            return True
+        except serial.SerialException as exc:
+            self._handle_serial_error(exc, f"write({context})")
+            return False
+
+    # ── ROS subscriptions ─────────────────────────────────────────────────
+
+    def _cmd_vel_cb(self, msg: Twist) -> None:
+        """Convert /cmd_vel to CMD_DRIVE at up to 50 Hz."""
+        self._last_cmd_time  = time.monotonic()
+        self._watchdog_sent  = False
+
+        speed = int(msg.linear.x  * self._speed_scale)
+        steer = int(msg.angular.z * self._steer_scale)
+        self._write(encode_drive(speed, steer), "cmd_vel")
+
+    def _estop_cb(self, msg: Bool) -> None:
+        frame = encode_estop(msg.data)
+        self._write(frame, "estop")
+        if msg.data:
+            self.get_logger().warning("E-stop asserted → CMD_ESTOP sent to ESP32-S3 BALANCE")
+
+    def _arm_cb(self, msg: Bool) -> None:
+        self._write(encode_arm(msg.data), "arm")
+
+    def _pid_cb(self, msg: String) -> None:
+        """Parse JSON {"kp":…,"ki":…,"kd":…} and send CMD_PID."""
+        try:
+            d = json.loads(msg.data)
+            kp = float(d["kp"])
+            ki = float(d["ki"])
+            kd = float(d["kd"])
+        except (KeyError, ValueError, json.JSONDecodeError) as exc:
+            self.get_logger().error(f"Bad /saltybot/pid_update JSON: {exc}")
+            return
+        self._write(encode_pid(kp, ki, kd), "pid_update")
+
+    # ── Timers ────────────────────────────────────────────────────────────
+
+    def _heartbeat_cb(self) -> None:
+        self._write(encode_heartbeat(), "heartbeat")
+
+    def _watchdog_cb(self) -> None:
+        """Send CMD_DRIVE(0,0) if /cmd_vel has been silent for command_timeout_s."""
+        if self._watchdog_sent:
+            return
+        if time.monotonic() - self._last_cmd_time > self._cmd_timeout:
+            self._write(encode_drive(0, 0), "watchdog")
+            self._watchdog_sent = True
+
+    # ── Background reader ─────────────────────────────────────────────────
+
+    def _reader_loop(self) -> None:
+        while rclpy.ok():
+            with self._ser_lock:
+                ser = self._ser if (self._ser and self._ser.is_open) else None
+            if ser is None:
+                time.sleep(0.05)
+                continue
+            try:
+                n = ser.in_waiting
+                if n:
+                    raw = ser.read(n)
+                else:
+                    time.sleep(0.002)
+                    continue
+            except serial.SerialException as exc:
+                self._handle_serial_error(exc, "reader_loop")
+                continue
+
+            for byte in raw:
+                frame = self._parser.feed(byte)
+                if frame is not None:
+                    self._dispatch(frame)
+
+    def _dispatch(self, frame) -> None:
+        try:
+            if isinstance(frame, StatusFrame):
+                self._handle_status(frame)
+            elif isinstance(frame, VescFrame):
+                self._handle_vesc(frame)
+            elif isinstance(frame, AckFrame):
+                self.get_logger().debug(
+                    f"ACK for cmd type 0x{frame.echoed_type:02X}"
+                )
+            elif isinstance(frame, NackFrame):
+                self.get_logger().warning(
+                    f"NACK cmd=0x{frame.cmd_type:02X} err=0x{frame.error_code:02X}"
+                )
+            elif isinstance(frame, tuple):
+                type_code, _ = frame
+                self.get_logger().debug(f"Unknown telemetry type 0x{type_code:02X}")
+        except Exception as exc:
+            self.get_logger().warning(f"Error dispatching frame {type(frame).__name__}: {exc}")
+
+    # ── Frame handlers ────────────────────────────────────────────────────
+
+    def _handle_status(self, f: StatusFrame) -> None:
+        """Publish balance controller status — replaces CAN 0x400 handler."""
+        now = self.get_clock().now().to_msg()
+        payload = {
+            "pitch_deg":    round(f.pitch_deg, 2),
+            "motor_cmd":    f.motor_cmd,
+            "vbat_mv":      f.vbat_mv,
+            "balance_state": f.balance_state,
+            "state_label":  BALANCE_STATE_LABEL.get(f.balance_state,
+                                                     f"UNKNOWN({f.balance_state})"),
+            "flags":        f.flags,
+            "estop_active": bool(f.flags & 0x01),
+            "hb_timeout":   bool(f.flags & 0x02),
+            "ts":           f"{now.sec}.{now.nanosec:09d}",
+        }
+        msg = String()
+        msg.data = json.dumps(payload)
+        self._pub_attitude.publish(msg)
+        self._pub_balance.publish(msg)
+
+        # Battery piggyback on STATUS frame for nodes that use /can/battery
+        bat = BatteryState()
+        bat.header.stamp = now
+        bat.voltage      = f.vbat_mv / 1000.0
+        bat.present      = True
+        bat.power_supply_status = BatteryState.POWER_SUPPLY_STATUS_DISCHARGING
+        self._pub_battery.publish(bat)
+
+    def _handle_vesc(self, f: VescFrame) -> None:
+        """Publish proxied VESC telemetry — replaces CAN VESC_STATUS_1 handler.
+
+        Float32MultiArray layout: [erpm, voltage_v, current_a, temp_c]
+        (duty not available via serial proxy; 0.0 placeholder)
+        """
+        arr = Float32MultiArray()
+        arr.data = [
+            float(f.erpm),
+            float(f.voltage_mv) / 1000.0,
+            float(f.current_ma) / 1000.0,
+            f.temp_c,
+        ]
+        if f.vesc_id == 56:
+            self._pub_vesc_left.publish(arr)
+        elif f.vesc_id == 68:
+            self._pub_vesc_right.publish(arr)
+        else:
+            self.get_logger().warning(f"Unknown VESC ID {f.vesc_id} in telemetry frame")
+
+    # ── Status helper ─────────────────────────────────────────────────────
+
+    def _publish_status(self, status: str) -> None:
+        msg = String()
+        msg.data = status
+        self._pub_status.publish(msg)
+
+    # ── Shutdown ──────────────────────────────────────────────────────────
+
+    def destroy_node(self) -> None:
+        # Send zero drive + estop before closing
+        self._write(encode_drive(0, 0), "shutdown")
+        self._write(encode_estop(True), "shutdown")
+        with self._ser_lock:
+            if self._ser is not None:
+                try:
+                    self._ser.close()
+                except Exception:
+                    pass
+            self._ser = None
+        super().destroy_node()
+
+
+def main(args=None) -> None:
+    rclpy.init(args=args)
+    node = Esp32BalanceNode()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        node.destroy_node()
+        rclpy.shutdown()
+
+
+if __name__ == "__main__":
+    main()

jetson/ros2_ws/src/saltybot_esp32_serial/saltybot_esp32_serial/esp32_balance_protocol.py

@@ -0,0 +1,355 @@
+"""esp32_balance_protocol.py — Binary frame codec for Orin↔ESP32-S3 BALANCE UART/USB comms.
+
+bd-wim1: replaces CANable2/python-can ESP32 interface with USB-CDC serial.
+Counterpart firmware bead: bd-66hx (hal's ESP32-S3 BALANCE side).
+
+Frame layout:
+  ┌───────┬─────┬──────┬──────────────────┬───────┐
+  │  SYNC │ LEN │ TYPE │     PAYLOAD      │  CRC8 │
+  │  0xAA │  1B │  1B  │    LEN bytes     │   1B  │
+  └───────┴─────┴──────┴──────────────────┴───────┘
+
+  LEN   = number of payload bytes (0–62)
+  CRC8  = CRC8-SMBUS (poly=0x07, init=0x00), computed over LEN+TYPE+PAYLOAD
+
+Physical layer
+  Device  : /dev/esp32-balance  (CH343 USB-CDC, VID:PID 1a86:55d3)
+  Baud    : 460800, 8N1
+
+Command types (Orin → ESP32-S3 BALANCE):
+  0x01  CMD_HEARTBEAT  — no payload                               len=0
+  0x02  CMD_DRIVE      — int16 speed_units, int16 steer_units     len=4  range −1000..+1000
+  0x03  CMD_ESTOP      — uint8 (1=assert, 0=clear)               len=1
+  0x04  CMD_ARM        — uint8 (1=arm, 0=disarm)                 len=1
+  0x05  CMD_PID        — float32 kp, float32 ki, float32 kd       len=12
+
+Telemetry types (ESP32-S3 BALANCE → Orin):
+  0x80  TELEM_STATUS      — int16 pitch_x10, int16 motor_cmd,
+                            uint16 vbat_mv, uint8 balance_state, uint8 flags   len=8
+  0x81  TELEM_VESC_LEFT   — int32 erpm, uint16 voltage_mv,
+                            int16 current_ma, uint16 temp_c_x10                len=10
+  0x82  TELEM_VESC_RIGHT  — same layout as TELEM_VESC_LEFT                     len=10
+  0xA0  RESP_ACK   — uint8 echoed cmd type                       len=1
+  0xA1  RESP_NACK  — uint8 cmd type, uint8 error_code            len=2
+
+Balance state values (TELEM_STATUS.balance_state):
+  0  DISARMED
+  1  ARMED
+  2  TILT_FAULT
+  3  ESTOP
+
+NACK error codes:
+  0x01  ERR_BAD_CRC
+  0x02  ERR_BAD_LEN
+  0x03  ERR_ESTOP_ACTIVE
+  0x04  ERR_DISARMED
+
+NOTE: Message type IDs coordinated with hal (bd-66hx) on 2026-04-17.
+      Confirm against bd-66hx PR before deploying on hardware.
+"""
+
+from __future__ import annotations
+
+import struct
+from dataclasses import dataclass
+from enum import IntEnum
+from typing import Optional
+
+# ── Physical layer constants ──────────────────────────────────────────────────
+
+SERIAL_PORT_DEFAULT = "/dev/esp32-balance"
+BAUD_RATE           = 460800
+MAX_PAYLOAD_LEN     = 62       # hard cap; larger frames are considered corrupt
+
+# ── Framing ───────────────────────────────────────────────────────────────────
+
+SYNC_BYTE = 0xAA
+
+
+# ── Command type codes (Orin → ESP32-S3 BALANCE) ─────────────────────────────
+
+class CmdType(IntEnum):
+    HEARTBEAT = 0x01
+    DRIVE     = 0x02
+    ESTOP     = 0x03
+    ARM       = 0x04
+    PID       = 0x05
+
+
+# ── Telemetry type codes (ESP32-S3 BALANCE → Orin) ───────────────────────────
+
+class TelType(IntEnum):
+    STATUS     = 0x80
+    VESC_LEFT  = 0x81
+    VESC_RIGHT = 0x82
+    ACK        = 0xA0
+    NACK       = 0xA1
+
+
+# ── Balance state enum ────────────────────────────────────────────────────────
+
+class BalanceState(IntEnum):
+    DISARMED   = 0
+    ARMED      = 1
+    TILT_FAULT = 2
+    ESTOP      = 3
+
+
+BALANCE_STATE_LABEL = {
+    BalanceState.DISARMED:   "DISARMED",
+    BalanceState.ARMED:      "ARMED",
+    BalanceState.TILT_FAULT: "TILT_FAULT",
+    BalanceState.ESTOP:      "ESTOP",
+}
+
+
+# ── Parsed telemetry dataclasses ─────────────────────────────────────────────
+
+@dataclass
+class StatusFrame:
+    """TELEM_STATUS (0x80): balance controller status at ~10 Hz."""
+    pitch_deg:     float   # degrees (positive = forward tilt); raw pitch_x10 / 10.0
+    motor_cmd:     int     # ESC command, −1000..+1000
+    vbat_mv:       int     # battery voltage, millivolts
+    balance_state: int     # BalanceState enum
+    flags:         int     # bitmask — bit 0: estop_active, bit 1: heartbeat_timeout
+
+
+@dataclass
+class VescFrame:
+    """TELEM_VESC_LEFT (0x81) or TELEM_VESC_RIGHT (0x82): VESC proxied telemetry at ~10 Hz."""
+    vesc_id:    int    # 56 = left, 68 = right (maps to CAN IDs from hardware spec)
+    erpm:       int    # electrical RPM (signed)
+    voltage_mv: int    # bus voltage, millivolts
+    current_ma: int    # phase current, milliamps (signed)
+    temp_c:     float  # motor temperature, °C; raw temp_c_x10 / 10.0
+
+
+@dataclass
+class AckFrame:
+    """RESP_ACK (0xA0): acknowledgement for a successfully parsed command."""
+    echoed_type: int
+
+
+@dataclass
+class NackFrame:
+    """RESP_NACK (0xA1): rejection; contains original cmd type and error code."""
+    cmd_type:   int
+    error_code: int
+
+
+TelemetryFrame = StatusFrame | VescFrame | AckFrame | NackFrame
+
+
+# ── CRC8-SMBUS ────────────────────────────────────────────────────────────────
+
+def _crc8(data: bytes) -> int:
+    """CRC8-SMBUS: polynomial 0x07, init 0x00, no final XOR.
+
+    Coverage: LEN + TYPE + PAYLOAD bytes.
+    """
+    crc = 0
+    for byte in data:
+        crc ^= byte
+        for _ in range(8):
+            if crc & 0x80:
+                crc = (crc << 1) ^ 0x07
+            else:
+                crc <<= 1
+        crc &= 0xFF
+    return crc
+
+
+# ── Frame encoder ─────────────────────────────────────────────────────────────
+
+def _build_frame(cmd_type: int, payload: bytes) -> bytes:
+    """Build a complete binary frame: [0xAA][LEN][TYPE][PAYLOAD][CRC8]."""
+    if len(payload) > MAX_PAYLOAD_LEN:
+        raise ValueError(f"Payload length {len(payload)} exceeds max {MAX_PAYLOAD_LEN}")
+    length = len(payload)
+    crc_data = bytes([length, cmd_type]) + payload
+    crc = _crc8(crc_data)
+    return bytes([SYNC_BYTE, length, cmd_type]) + payload + bytes([crc])
+
+
+def encode_heartbeat() -> bytes:
+    """CMD_HEARTBEAT — no payload. Send every ≤500 ms to keep watchdog alive."""
+    return _build_frame(CmdType.HEARTBEAT, b"")
+
+
+def encode_drive(speed: int, steer: int) -> bytes:
+    """CMD_DRIVE — int16 speed_units + int16 steer_units (big-endian, −1000..+1000).
+
+    Parameters
+    ----------
+    speed : target longitudinal speed in motor units (positive = forward)
+    steer : steering demand in motor units (positive = right turn)
+    """
+    speed = max(-1000, min(1000, int(speed)))
+    steer = max(-1000, min(1000, int(steer)))
+    return _build_frame(CmdType.DRIVE, struct.pack(">hh", speed, steer))
+
+
+def encode_estop(assert_stop: bool) -> bytes:
+    """CMD_ESTOP — uint8, 1=assert, 0=clear."""
+    return _build_frame(CmdType.ESTOP, struct.pack("B", 1 if assert_stop else 0))
+
+
+def encode_arm(arm: bool) -> bytes:
+    """CMD_ARM — uint8, 1=arm, 0=disarm."""
+    return _build_frame(CmdType.ARM, struct.pack("B", 1 if arm else 0))
+
+
+def encode_pid(kp: float, ki: float, kd: float) -> bytes:
+    """CMD_PID — three float32 values, big-endian."""
+    if kp < 0.0 or ki < 0.0 or kd < 0.0:
+        raise ValueError("PID gains must be non-negative")
+    return _build_frame(CmdType.PID, struct.pack(">fff", kp, ki, kd))
+
+
+# ── Frame decoder (streaming state-machine) ───────────────────────────────────
+
+class _ParseState(IntEnum):
+    WAIT_SYNC = 0
+    WAIT_LEN  = 1
+    WAIT_TYPE = 2
+    PAYLOAD   = 3
+    WAIT_CRC  = 4
+
+
+class FrameParser:
+    """Byte-by-byte streaming parser for ESP32-S3 BALANCE telemetry frames.
+
+    Feed individual bytes via ``feed()``; returns a decoded dataclass when a
+    complete, CRC-valid frame arrives, otherwise returns ``None``.
+
+    Not thread-safe — guard with a lock if accessed from multiple threads.
+
+    Counters
+    --------
+    frames_ok     : successfully decoded frames
+    frames_error  : CRC failures or oversized payloads
+    """
+
+    def __init__(self) -> None:
+        self.frames_ok    = 0
+        self.frames_error = 0
+        self._reset()
+
+    def reset(self) -> None:
+        """Reset to initial state — call after serial reconnect."""
+        self._reset()
+
+    def _reset(self) -> None:
+        self._state   = _ParseState.WAIT_SYNC
+        self._length  = 0
+        self._type    = 0
+        self._payload = bytearray()
+
+    def feed(self, byte: int) -> Optional[TelemetryFrame | tuple]:
+        """Process one byte.
+
+        Returns a decoded dataclass on success, ``None`` while waiting for more
+        bytes, or a ``(type_code, raw_payload)`` tuple for unrecognised types.
+        """
+        s = self._state
+
+        if s == _ParseState.WAIT_SYNC:
+            if byte == SYNC_BYTE:
+                self._state = _ParseState.WAIT_LEN
+            return None
+
+        if s == _ParseState.WAIT_LEN:
+            if byte > MAX_PAYLOAD_LEN:
+                self.frames_error += 1
+                self._reset()
+                return None
+            self._length = byte
+            self._state  = _ParseState.WAIT_TYPE
+            return None
+
+        if s == _ParseState.WAIT_TYPE:
+            self._type    = byte
+            self._payload = bytearray()
+            if self._length == 0:
+                self._state = _ParseState.WAIT_CRC
+            else:
+                self._state = _ParseState.PAYLOAD
+            return None
+
+        if s == _ParseState.PAYLOAD:
+            self._payload.append(byte)
+            if len(self._payload) == self._length:
+                self._state = _ParseState.WAIT_CRC
+            return None
+
+        if s == _ParseState.WAIT_CRC:
+            # Verify CRC before resetting parser state
+            crc_data = bytes([self._length, self._type]) + self._payload
+            expected = _crc8(crc_data)
+            if byte != expected:
+                self.frames_error += 1
+                self._reset()
+                return None
+            self.frames_ok += 1
+            result = _decode(self._type, bytes(self._payload))
+            self._reset()
+            return result
+
+        self._reset()
+        return None
+
+
+# ── Telemetry decoder ─────────────────────────────────────────────────────────
+
+# Maps VESC_LEFT/RIGHT type codes to hardware CAN IDs (from memory)
+_VESC_ID_MAP = {
+    TelType.VESC_LEFT:  56,   # left VESC CAN ID
+    TelType.VESC_RIGHT: 68,   # right VESC CAN ID
+}
+
+
+def _decode(type_code: int, payload: bytes) -> Optional[TelemetryFrame | tuple]:
+    """Decode a validated telemetry payload into a typed dataclass."""
+    try:
+        if type_code == TelType.STATUS:
+            # int16 pitch_x10, int16 motor_cmd, uint16 vbat_mv, uint8 state, uint8 flags
+            if len(payload) < 8:
+                return None
+            pitch_x10, motor_cmd, vbat_mv, state, flags = struct.unpack_from(">hhHBB", payload)
+            return StatusFrame(
+                pitch_deg=pitch_x10 / 10.0,
+                motor_cmd=motor_cmd,
+                vbat_mv=vbat_mv,
+                balance_state=state,
+                flags=flags,
+            )
+
+        if type_code in (TelType.VESC_LEFT, TelType.VESC_RIGHT):
+            # int32 erpm, uint16 voltage_mv, int16 current_ma, uint16 temp_c_x10
+            if len(payload) < 10:
+                return None
+            erpm, voltage_mv, current_ma, temp_x10 = struct.unpack_from(">iHhH", payload)
+            return VescFrame(
+                vesc_id=_VESC_ID_MAP[type_code],
+                erpm=erpm,
+                voltage_mv=voltage_mv,
+                current_ma=current_ma,
+                temp_c=temp_x10 / 10.0,
+            )
+
+        if type_code == TelType.ACK:
+            if len(payload) < 1:
+                return None
+            return AckFrame(echoed_type=payload[0])
+
+        if type_code == TelType.NACK:
+            if len(payload) < 2:
+                return None
+            return NackFrame(cmd_type=payload[0], error_code=payload[1])
+
+    except struct.error:
+        return None
+
+    # Unknown type — return raw for forward-compatibility
+    return (type_code, payload)

jetson/ros2_ws/src/saltybot_esp32_serial/setup.cfg

@@ -0,0 +1,5 @@
+[develop]
+script_dir=$base/lib/saltybot_esp32_serial
+
+[install]
+install_scripts=$base/lib/saltybot_esp32_serial

jetson/ros2_ws/src/saltybot_esp32_serial/setup.py

@@ -0,0 +1,27 @@
+from setuptools import setup
+
+package_name = "saltybot_esp32_serial"
+
+setup(
+    name=package_name,
+    version="0.1.0",
+    packages=[package_name],
+    data_files=[
+        ("share/ament_index/resource_index/packages", [f"resource/{package_name}"]),
+        (f"share/{package_name}", ["package.xml"]),
+        (f"share/{package_name}/config", ["config/esp32_balance_params.yaml"]),
+        (f"share/{package_name}/launch", ["launch/esp32_balance.launch.py"]),
+    ],
+    install_requires=["setuptools", "pyserial"],
+    zip_safe=True,
+    maintainer="sl-perception",
+    maintainer_email="sl-perception@saltylab.local",
+    description="UART/USB-CDC serial bridge for ESP32-S3 BALANCE (bd-wim1)",
+    license="MIT",
+    tests_require=["pytest"],
+    entry_points={
+        "console_scripts": [
+            "esp32_balance_node = saltybot_esp32_serial.esp32_balance_node:main",
+        ],
+    },
+)