SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
With UHS cards, the gap timing between two successive cards is extended from two cycles to four cycles. It provides more flexibility for the host Auto CMD12 arrival to receive the last complete and reliable block. The MMCHS controller follows only the left border case defined by the SD UHS specification.
Figure 27-29 shows Auto CMD12 timings during read transfer.
Figure 27-29 Auto CMD12 Timings During Read TransferThe Auto CMD12 arrival sent by the host controller is not sensitive to the MMC/SD bus configuration, whether it is a DDR or standard transfer and whether it is a 1-, 4-, or 8-bit bus width transfer.