50.7.4.1.2 Autobaud Mode
The Autobaud feature is enabled by setting the CAN_MR.ABM field. In this mode, the CAN controller is only listening to the line without acknowledging the received messages. It can not send any message. The errors flags are updated. The bit timing can be adjusted until no error occurs (good configuration found). In this mode, the error counters are frozen. To go back to the standard mode, clear ABM.