SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
A margin named Ncrc in the range of two to eight cycles has been defined for SDR50 and SDR104 card components for write data transfers, because the Auto CMD12 end bit must arrive after the CRC status end bit.
Figure 25-28 shows the Auto CMD12 timings during write transfer.
The host controller has a margin of 18 clock cycles to enure that the Auto CMD12 end bit arrives after the CRC status. This margin does not depend on the MMC/SD bus configuration, DDR, or standard transfer, 1-, 4-, or 8-bit bus width.