上位机部分：只说说我用到的一些函数，和遇到的问题。基本的比如什么是异步通讯啦之类的就不说了，随便网上一搜能找一箩筐！-PC part: I only talk about some of the functions used, and problems encountered. What is the basic asynchronous communication such as the kind of friends do not say, just a search online to f