这个程序实现的是接收字符，再把这个字符串口发送。

还要一个要注意的是波特率，而波特率附送的小程序算出

实验方法:打开串口调试程序（小工具目录里）选择您正确的串口号，波特率选9600，

然后发送一串字符，这一串字符就马上会被单片机回发到电脑-The program implementation is to receive characters, then this string I send. Also one should note that the baud rate, while the baud rate accompanied by a small program calculates experimental method: Open the serial port debugger (small tools directory) Choose your correct serial number, baud rate 9600 election, and then send a bunch of characters, this will be a string of characters immediately back to the computer microcontroller