说明：  当前时间送电脑同时显示,用RS232运用串口通信送数据给电脑，开中断计算时间，精确到秒。Keil C51开发环境，是一个整合很多技术的程序。
(current time to send the computer also showed that use RS232 serial data communications sent to the computer, open interrupted computing time, accurate to the second. Keil C51 development environment, integration is a lot of technical procedure.)