该例程实现读写SD卡文件的功能。移植了FatFS文件系统。

SD Memory Card Specifications part1 PHYSICAL LAYER SPECIFICATION(v1.01, v1.10, v2.00, v3.01, v4.01) SD Memory Card Specifications Part 2 FILE SYSTEM SPECIFICATION v1.0 SD Specifications Part A1 Advanced Security SD Extension Simplified Specification v2.00 SD Specification Part A2 SD Host Controller Standard Simplified Specification (v1.00, v2.00, v3.00) SD Card Specification Secure Digital Input/Output (SDIO)Card Specification(v1.00, v1.10, v2.00, v3.00) SD Specifications Part E2 SDIO Card Bluetooth Type-A Simplified Specification Version 1.00

3.3STM32固件库，008B最新的FATFS文件系统。非常完善的SDIO例程和文件系统的建立。非常通俗易懂

基于ST例程V4.5.0，修正了少量bug。固件库函数请用3.5，否则初始化出错。