DM642的USB接口及其研究 主要用于用单片机的USB接口实时跟踪 -DM642' s USB port and its research is mainly used with MCU USB interface to real-time tracking

STC 的单片机使用SL811 实现 U盘读写，包括Excel文件的读取等. 并且带有广告牌的各种控制协议-this project for usb read and write base on sl811