j1850-uart
J1850PWM to CDC/UART adapter based on STM32
Simple tool for communicating with J1850 PWM bus (MSM6636/MSM6636B) using interrupts.
This bus commonly used in Nissan and Infinity cars for Xanavi/Clarion multimedia, steering wheel buttons and dash monitor control.
Used STM32F103C8T6 chip's two hardware timers:
- TIM2 PWM Capture - JNet SOF & Bits reading
- TIM3 overrun interrupt - read timeouts and w/o interrupt - generation.
DONE:
- JNET
- Detect SOF, EOF.
- Read from JNet (CRC Fast checked w/pre generated table).
- Make IFR after EOD if enabled (AUTOIFR in config.h).
- Write to JNet.
- CDC
- Send up to 11 bytes right filled with 0x00 packets to CDC
- Read packets from CDC (CR is terminator)
WIP:
- Documentation (Build, Schematic, PCB)
- JNet from/to UART
BUILD:
- Need STM32CUBEF1 library (tested with v1.6.0) - place Drivers and Middlewares in project dir.
USAGE:
- Nissan Gloria ENY34: https://www.drive2.ru/l/463617875018515146/
WONTFIX: Collision detection
Adapter schematic prototype v0.1:
