Compatibility
Vehicle Firmware Compatibility
Update
Do not update to 2026.2.9.x & 2026.8.6 — FSD is not working on HW4.
| Firmware | HW3 | HW4 | Notes |
|---|---|---|---|
| < 2026.2.9 | FSD v12.4.6 | Compile as HW3 | HW4 vehicles use HW3 handler for FSD v13 |
| 2026.2.9.X | FSD v12.4.6 | FSD v14.x | HW4 gets full v14 features |
| 2026.8.X | FSD v12.4.6 | FSD v12.4.6 | HW4 on this branch is still v12/v13 — compile as HW3 |
FSD Version Differences
FSD v12/13 (HW3 handler)
- FSD enable bit
- Speed profiles (3 levels)
- Nag suppression
FSD v14 (HW4 handler)
- FSD enable bit
- Speed profiles (5 levels)
- Nag suppression
- Actually Smart Summon (ASS)
- Emergency Vehicle Detection (optional)
- ISA Speed Chime Suppress (optional)
Board Compatibility
All supported boards run the same shared firmware logic. The only difference is the CAN driver implementation:
| Board | PlatformIO Env | Arduino Board |
|---|---|---|
| Feather RP2040 CAN | feather_rp2040_can | rp2040:rp2040:adafruit_feather_can |
| Feather M4 CAN Express | feather_m4_can | Feather M4 CAN (SAME51) |
| ESP32 + Transceiver | esp32_twai | ESP32 Dev Module |
| M5Stack Atomic CAN Base | m5stack-atomic-can-base | M5Stack-ATOM |
Third-Party Libraries
| Library | License | Used By |
|---|---|---|
| autowp/arduino-mcp2515 | MIT | Feather RP2040 CAN |
| adafruit/Adafruit_CAN | MIT | Feather M4 CAN Express |
| espressif/esp-idf (TWAI) | Apache 2.0 | ESP32 boards |