说明：  佟国香的基于单片机的嵌入式系统开发课件PPT,主要介绍日电的NEC单片机，非常经典，国内NEC资料比较少，要用的抓紧了
(Tong Guoxiang microcontroller-based embedded system development courseware PPT, Xinhua introduced the NEC microcontroller, very classic, less domestic NEC data, use the hold on tight)