Issue #680 — IMU mount angle calibration:
- imu_cal_flash.h/.c: store pitch/roll offsets in flash sector 7
(0x0807FF00, 64 bytes; preserves PID records across sector erase)
- mpu6000_set_mount_offset(): subtracts offsets from pitch/roll output
- mpu6000_has_mount_offset(): reports cal_status=2 to Orin
- 'O' CDC command: capture current pitch/roll → save to flash → ACK JSON
- Load offsets on boot; report in printf log
CAN telemetry correction (Tee: production has no USB to Orin):
- FC_IMU (0x402): pitch/roll/yaw/cal_status/balance_state at 50 Hz
- orin_can_broadcast_imu() rate-limited to ORIN_IMU_TLM_HZ (50 Hz)
- FC_BARO (0x403): pressure_pa/temp_x10/alt_cm at 1 Hz (Issue #672)
- orin_can_broadcast_baro() rate-limited to ORIN_BARO_TLM_HZ (1 Hz)
Issue #685 — LED CAN override:
- ORIN_CAN_ID_LED_CMD (0x304): pattern/brightness/duration_ms from Orin
- orin_can_led_override volatile state + orin_can_led_updated flag
- main.c: apply pattern to LED state machine on each LED_CMD received
Orin side:
- saltybot_can_node.py: production SocketCAN bridge — reads 0x400-0x403,
publishes /saltybot/imu, /saltybot/balance_state, /saltybot/barometer;
subscribes /cmd_vel → 0x301 DRIVE; /saltybot/leds → 0x304 LED_CMD;
sends 0x300 HEARTBEAT at 5 Hz; sends 0x303 ESTOP on shutdown
- setup.py: register saltybot_can_node entry point + uart_bridge launch
Fix: re-apply --defsym __stack_end=_estack-0x1000 linker fix to branch
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add 'G' CDC command that disarms and re-runs gyro bias calibration.
safety_refresh() added to calibration loop (every 40ms) so IWDG
does not trip during the 1s blocking re-cal when watchdog is running.
GYRO CAL button in ui/index.html sends 'G' and shows status feedback.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Root cause 1 (IWDG reset loop): safety_init() was called before
mpu6000_init() — IWDG 50ms timeout fires during ~510ms IMU init,
causing infinite MCU reset. Moved safety_init() to after all
peripheral inits (IMU, hoverboard, balance).
Root cause 2 (DCache coherency): USB TX/RX buffers merged into a
single 512B-aligned struct in usbd_cdc_if.c. MPU Region 0 configured
non-cacheable (TEX=1, C=0, B=0) in usbd_conf.c USBD_LL_Init() before
HAL_PCD_Init(). DCache stays ON globally — MPU handles coherency.
Removed SCB_DisableDCache() from main.c (caused boot crash).
Also: fix safety.c IWDG_RELOAD macro (float literals not valid in
#if); add crsf.c stub so crsf_state links (UART not yet wired).
Fixes issue #9.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add USB command interface for live PID gain adjustment without reflashing:
P<kp> I<ki> D<kd> T<setpoint_deg> M<max_speed> ?
Command parsing runs in main loop (sscanf-safe), not in USB IRQ.
USB IRQ copies command to shared volatile buffer (cdc_cmd_buf), sets flag.
Acknowledgement echoes current gains: {"kp":...,"ki":...,"kd":...}
Bounds checking: kp 0-500, ki/kd 0-50, setpoint ±20°, max_speed 0-1000.
Gains validated before write — silently ignored if out of range.
Telemetry updated from raw counts to physical tuning signals:
pitch (°x10), pitch_rate (°/s x10), error (°x10),
integral (x10 for windup monitoring), motor_cmd, state
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Bug 1 (PRIMARY — DCache/USB coherency):
SCB_DisableDCache() was buried inside icm42688_init(), called ~3.5s
after USB starts. STM32F7 DCache/USB coherency issue: when DCache is
on (enabled by SystemInit()), CPU writes to TX buffers stay in cache
and the USB hardware reads stale SRAM data. Moved SCB_DisableDCache()
to main() before HAL_Init(), ensuring coherency for all USB transfers.
Bug 2 (USB TX corruption):
CDC_Transmit() passed the caller's stack-allocated buf pointer directly
to the USB stack. The USB TXFE interrupt fires asynchronously; by then
the stack buffer may have been modified by the next loop iteration.
CDC_Transmit() now copies into the static UserTxBuffer before handing
off to the USB hardware, ensuring the buffer is stable for the transfer.
Bug 3 (IMU type mismatch → wrong data to balance):
main.c called icm42688_init()/icm42688_read() directly, passing
icm42688_data_t* (raw int16 ax/ay/az/gx/gy/gz) to balance_update()
which expects IMUData* (float pitch/pitch_rate from complementary
filter). Type mismatch produced garbage balance values. Fixed by using
mpu6000_init()/mpu6000_read() which wraps icm42688 + sensor fusion.
Telemetry updated to report fused pitch/rate instead of raw ADC counts.
Also fix icm42688_init() returning 0 on who==0 (no SPI response),
which falsely indicated IMU success.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
