从USB端口读数据，计算相应的特征值，并写入映射文件中-Read data from the USB port, the corresponding eigenvalue calculation, and write the mapping file

基于Silabs的USB鼠标源码修改，参考了圈圈教你玩usb的代码，实现了板载按键映射键盘A键和S键-Silabs USB mouse source code based on modified reference circle to teach you to play the USB code, and realizes the load button keyboard mapping a button and s keys