说明：  eMMC4.4标准协议，最新的。是研究eMMC4.4的必看文档，适合芯片、底软驱动人员。
(Embedded MultiMediaCard (e• MMC) e• MMC/Card Product Standard, High Capacity, including Reliable Write, Boot, Sleep Modes, Dual Data Rate, Multiple Partitions Supports and Security Enhancement)