说明：  从输入文件如in.txt读取数据(可以是当前目录，最好是可以由用户指定)，经com1端口发送（自发自收），收到的内容存入输出文件如out.txt(可以是当前目录，最好是可以由用户指定)。要求在按键后启动发送，并开始计时，发送完毕后，结束计时，并显示发送所花时间（分钟：秒：毫秒）。
(In.txt from the input file such as read data (the current directory can be the best can be specified by the user), the com1 port send (spontaneous self-admission), received the contents into the output file, such as out.txt (can be the current directory, it is best can be specified by the user). Requested after the start button to send, and start running, sent after the end of time, and display the time spent sending (minutes: seconds: milliseconds).)