38.11.3.1 Invalid Message Interrupt - IVMIF
If a CAN bus error or DLC mismatch is detected during the last message transmitted or received, the IVMIF bit will be set. The CxBDIAG1 register sets a flag for each error. The flag must be cleared by the application.
The following CAN bus errors will trigger the interrupt in case an error frame is transmitted: CRC, stuff bit, form, bit or ACK.
The flag will not be set if the ESI of a received message is set.