SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
By default, after the DCAN has entered Bus-Off state, the software can start a Bus-Off-Recovery sequence by resetting the DCAN_CTL[0] INIT bit to 0. If this is not done, the module will stay in Bus-Off state.
The DCAN provides an automatic Auto-Bus-On feature which is enabled by bit DCAN_CTL[9] ABO. If set, the DCAN will automatically start the Bus-Off-Recovery sequence. The sequence can be delayed by a user-defined number of interface clock cycles which can be defined in the Auto-Bus-On Time register (DCAN_ABOTR).
If the DCAN goes to Bus-Off state due to a massive occurrence of CAN bus errors, it stops all bus activities and automatically sets the INIT bit. Once the INIT bit has been reset by the software or due to the Auto-Bus-On feature, the device will wait for 129 occurrences of bus Idle (equal to 129 × 11 consecutive recessive bits) before resuming normal operation. At the end of the Bus-Off recovery sequence, the error counters will be reset.