FDCAN: Retransmissions Configuration

[MFrie.7]

Good afternoon
I am working on the STM32H755 and am dealing with the retransmissions from my CAN FD periphery. According to the ISO-11898-1:2024 standard, the number of retransmissions should be configurable:
"
- from 0 (no retransmission),
- to at least 6 (6 retransmission attempts),
- and the highest number in this range can allow unlimited retransmission attempts.
"
Currently I have FunctionalState AutoRetransmission in FDCAN_InitTypeDef set to ENABLE and on the oscilloscope I see an infinite number of retransmissions when I disconnect between two nodes. Now I want to limit the retransmission count to 6 retransmissions.
Can I do this?
Thank you very much for your answer.
Manuel

[ahsrabrifat]

You can monitor the Transmit Error Counter (TEC) in the FDCAN Protocol Status Register (PSR) and count the retransmissions in software. If the transmission is failing, keep a counter and manually stop retransmission after 6 attempts.