60.5.1.7.1 Frame Transmission in DAR Mode
In DAR mode, all transmissions are automatically cancelled after they start on the CAN bus. A Tx Buffer’s Tx Request Pending bit TXBRP.TRPx is reset after successful transmission, when a transmission has not yet been started at the point of cancellation, has been aborted due to lost arbitration, or when an error occurred during frame transmission.
- Successful transmission:
- Corresponding Tx Buffer Transmission Occurred bit MCAN_TXBTO.TOx set
- Corresponding Tx Buffer Cancellation Finished bit MCAN_TXBCF.CFx not set
- Successful transmission in spite of cancellation:
- Corresponding Tx Buffer Transmission Occurred bit MCAN_TXBTO.TOx set
- Corresponding Tx Buffer Cancellation Finished bit MCAN_TXBCF.CFx set
- Arbitration lost or frame transmission disturbed:
- Corresponding Tx Buffer Transmission Occurred bit MCAN_TXBTO.TOx not set
- Corresponding Tx Buffer Cancellation Finished bit MCAN_TXBCF.CFx set
In case of a successful frame transmission, and if storage of Tx events is enabled, a Tx Event FIFO element is written with Event Type ET = “10” (transmission in spite of cancellation).