使用方法：自己重新写一个串口操作源文件cmd.c或者cmd.cpp.在cmd.c或者cmd.cpp中定义头文件#include "cnComm.h".定义串口类-To Usage: own re-write a serial operation source file cmd.c or cmd.cpp cmd.c, or cmd.cpp in defining the header file# include "cnComm.h define the serial port class