该文档介绍了SD卡的一般原理及相关结构，包括IO口的介绍等，文档内部赋有SD相关的Atmega128单片机读写程序，希望对你有帮助-This document describes the general principles of the SD card and related structures, including the introduction of IO port within the document are endowed with SD Related Atmega128 microcontroller to read and write procedures, you want to help