31.2.7.4 Auto Repeat Usage Model

When the Auto Repeat bit selects repeat mode, the CRC operation only exits at the end of a loop if there is a comparison error. The error causes the logic to set both CRCDONE and CRCERR. To restart the CRC, simply clear CRCDONE and CRCERR before setting CRCEN again.

If there is no comparison error the logic restarts the CRC operation by loading the IV into ACC, the MLEN into the length counter, and Period into the Period counter. CRCDONE, CRCERR, and CRCEN remain unchanged. As mentioned above, each read waits the Period count including the first read of a loop. The CRC operation continues looping until it detects an error or is stopped manually.