I encountered stange behavior of stm32f405rg while working with CAN. My setup: beaglbone black connected to stm over CAN bus. Data transmitted successfully, beaglbone is able to receive data correctly however ACK is not generated because of extra STM32 impulse.
CAN bus configuration:
- Bitrate: 25kBit/s.
- Time quanta: 2500nS.
- Propagation + first phase length: 13 time quantas.
- Second phase length: 2 time quantas.
- SWJ length: 1 time quanta.
These settings are equal for BB and STM.
As you can see STM32 tries to transmit something while BB generates ACK for the message. What are the possible reasons for that?