The SDMMC Host Controller handles SDIO/SD protocol at transmission level, packing data, adding cyclic redundancy check (CRC), start/end bit, and checking for transaction format correctness. Some useful applications of the SDMMC includes memory extension, data logging, and firmware update.
• System Interface
– Data transfer using Programmed IO mode on AHB Slave interface
• SD/SDIO/MMC Card Interface
– Transfers data in 1 bit and 4 bit SD modes and SPI mode
– Cyclic Redundancy Check CRC7 for command and CRC16 for data integrity
– Variable-length data transfers for SD/SDIO cards
– Designed to work with SD I/O cards, Read-only cards and Read/Write cards
– Supports Read wait Control, and Suspend/Resume operation for SD/SDIO cards
– Supports MMC Plus and MMC Mobile
– MMC Card detection for insertion/removal
– Error Correction Codes (ECC) for eMMC 4.4 cards
– Password protection for MMC cards
– Two 512 byte buffer for data transfers between core and cards
– Handles FIFO overrun and underrun conditions
