SD卡驱动学习

https://blog.csdn.net/zqixiao_09/article/category/6163492

sd 协议解析： https://blog.csdn.net/g_salamander/article/details/14167055 

　　已经看到 2、Response：应答是卡片发回数据的令牌

SDIO总线协议:https://blog.csdn.net/u012041204/article/details/72597806