# SaltyLab Firmware — Agent Playbook

## Project
**SAUL-TEE** — 4-wheel wagon robot (870×510×550 mm, 23 kg).
Two ESP32-S3 boards + Jetson Orin for AI/ROS2.

> **Full hardware spec:** `docs/SAUL-TEE-SYSTEM-REFERENCE.md`

### Embedded boards
| Board | Hardware | Role |
|-------|----------|------|
| **ESP32-S3 BALANCE** | Waveshare Touch LCD 1.28 (CH343 USB) | QMI8658 IMU, PID balance loop, CAN→VESCs (SN65HVD230, 500 kbps) |
| **ESP32-S3 IO** | Bare DevKit (JTAG USB) | BTS7960 motors, TBS Crossfire (UART0) + ELRS failover (UART2), NFC/baro/ToF (I2C), WS2812 LEDs, horn/headlight/fan/buzzer |

### Key protocols
- **Orin ↔ BALANCE:** CAN 500 kbps via CANable2 (slcan0). Cmds 0x300–0x303, telemetry 0x400–0x401
- **BALANCE ↔ IO:** UART 460800 baud, frame `[0xAA][LEN][TYPE][PAYLOAD][CRC8]`
- **VESC IDs:** Left = 56, Right = 68

## Team
| Agent | Role | Focus |
|-------|------|-------|
| **sl-firmware** | Embedded Firmware Lead | ESP32-S3 firmware (PlatformIO), QMI8658 IMU, PID, VESC CAN, inter-board UART |
| **sl-controls** | Control Systems Engineer | PID tuning, IMU sensor fusion, real-time control loops, safety systems |
| **sl-perception** | Perception / SLAM Engineer | Jetson Orin, RealSense D435i, RPLIDAR, ROS2, Nav2 |

## Status
Architecture migrated from Mamba F722S/BlackPill → ESP32-S3 BALANCE + IO (PR #712, 2026-04-04).

## Repo Structure
- `projects/saltybot/SALTYLAB.md` — Design doc
- `USB_CDC_BUG.md` — USB peripheral conflict details
- `TEAM.md` — Team roles specification

## Branch Strategy (issue #28)

### Variant branches
| Branch | Purpose |
|--------|---------|
| `saltylab` | Stable — SaltyLab 2-wheel balance bot (promoted from saltylab-dev) |
| `saltylab-dev` | Integration — SaltyLab balance bot; agents target this branch |
| `saltyrover` | Stable — 4-wheel rover variant |
| `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) |

### 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`
- 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`

### Git Workflow
- Branch naming: `<agent>/<slug>` (e.g., `sl-firmware/usb-cdc-fix`)
- For shared code targeting `main`: `<agent>/bd-<id>-<slug>`
- Before every push: `git fetch origin && git rebase origin/<base-branch>`
- Gitea: `gitea.vayrette.com/seb/saltylab-firmware`

## Communication
- Report progress to max via MQTT: `AGENT_NAME=<agent> ~/agent-mqtt/agent-send max "<message>"`
- Check inbox: `~/agent-mqtt/agent-read 2>/dev/null | tail -15`
- Prioritize messages from max (PM)

## Beads (Task System)
```bash
cd /Users/seb/AI/saltylab-firmware
br list                    # List open beads
br update <id> --claim     # Claim a bead
br close <id> --reason "Done. PR #N"
br comment <id> "message"
```