编一程序，在显示器上显示时、分、秒，借用计数器8253的Timer0作为中断源，通过8259A向CPU发送中断，每10ms产生一次中断。在中断服务程序中管理刷新时、分、秒。

输入文件名（如：CLK）后清屏显示：Current：xx:xx:xx(时分秒键盘输入)，打回车，时分秒开始计时，始终不停刷新。当键入ctrl+c时，停止计时，返回系统，且系统正常运行不死机。

-Compile a program that is displayed on the monitor, minutes, seconds, borrow counter Timer0 8253 as the interrupt source by sending an interrupt to the 8259A CPU, an interrupt is generated every 10ms. When the interrupt service routine management refresh, minutes and seconds.

       　Enter the file name: After (such as CLK) clear screen display: Current: xx: xx: xx (keyboard input when minutes and seconds), hit Enter, minutes and seconds start time, and always kept refreshed. When you type ctrl+ c, stop the clock and return system, and the system is running without crashes.