这是一个很好的eMMC协议，详细讲述了eMMC协议（英文版）。

emmc4.41 协议文档，官方 英文版。 The MMC/e•MMC is an universal low cost data storage and communication media. It is designed to cover a wide area of applications as smart phones, cameras, organizers, PDAs, digital recorders, MP3 players, pagers, electronic toys, etc. Targeted features are high mobility and high performance at a low cost price. These features include low power consumption and high data throughput at the memory card interface.