Transmitter Delay Measurement

If transmitter delay compensation is enabled by programming MCAN_DBTP.TDC = ‘1’, the measurement is started within each transmitted CAN FD frame at the falling edge of bit FDF to bit res. The measurement is stopped when this edge is seen at the receive input CANRX of the transmitter.

The resolution of this measurement is one mtq.

Figure 1. Transmitter Delay Measurement

To avoid that a dominant glitch inside the received FDF bit ends the delay compensation measurement before the falling edge of the received res bit, resulting in a to early SSP position, the use of a transmitter delay compensation filter window can be enabled by programming MCAN_TDCR.TDCF.

This defines a minimum value for the SSP position. Dominant edges on CANRX, that would result in an earlier SSP position are ignored for transmitter delay measurement. The measurement is stopped when the SSP position is at least MCAN_TDCR.TDCF AND CANRX is low.