The MCAN module provides a delay compensation mechanism to compensate the transmitter delay. The compensation mechanism enables transmission with higher bit rates during the CAN FD data phase. The transmitter delay compensation is enabled by setting the MCAN_DBTP[23] TDC bit to 1.

Users do not need to measure the transceiver loop-back delay or refer to the transceiver documentation for the same. Users need to program the SSP position, which is the same as the Sampling Point (SP). In case of CAN FD, make sure the Transceiver Delay Compensation value is correctly programmed. The Transmission Delay Compensation Value (TDCV) used as the Secondary Sample Point (SSP) is selected automatically by the CAN controller. The controller measures the delay between when a dominant signal is driven on m_can_tx to when the corresponding edge appears on m_can_rx, sampling every tq. This measured value is updated in the TDCV field of the Protocol Status Register (PSR address=h1044) at each transmission of CAN FD frame, is used as reference, and is used during the data portion of CAN FD transmission to verify good transmission.

The SSP that is selected by the CAN controller can be restricted to a certain window using the Transmitter Delay Compensation Offset (TDCO) and Filter Window Length (TDCF). The offset provides extra amount of time quanta to be added to the delay measurement of the CAN controller. The filter window length defines a minimum valid delay measurement, making sure the SSP is greater than the value defined here. These values can be configured in the Transmitter Delay Compensation Register (TDCR address=h1048).

This SSP position is in the data phase the number of mtq between the start of the transmitted data bit and the secondary sample point. Valid values are 0 to 127 mtq.