基于宽电压范围的Atmega 128L 8位单片机在 winavr环境下，使用C语言实现了单片机对SD卡的读写，程序有注解！-Wide voltage range based on Atmega 128L 8-bit microcontroller in winavr environment, using C language implementation of the microcontroller to read and write on the SD card, the program h