SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
The CPRMII transmit (TX) interface converts the CPGMAC MII input data into the RMII transmit format. The data is then output to the external RMII PHY.
The CPGMAC does not source the transmit error (MII_TXERR) signal. Any transmit frame from the CPGMAC with an error (underrun) will be indicated as an error by an error CRC. Transmit error is assumed to be de-asserted at all times and is not an input into the CPRMII module. Zeroes are output on RMII_TXD[1:0] for each clock that RMII_TXEN is de-asserted.