首先，分别对8255、8253进行初始化，设置8255为A口、C口输出，设置8253的计数器0为工作模式3；其次，设置IRQ7的中断矢量，使得有IRQ7中断时调用SERVER；再次，调用INIT对计数值初始化；最后，主程序循环等待中断，开始秒表的计时。 2、 INIT子程序-First, the 8255,8253 initialization, set for the 8255 A-C mouth output, set 8253 as the Counter mode 0 3; Second, set up the interruption vector there, make it there interruption call SERVER; Again, call curl_setopt early to count before; Finally, the cycle of waiting for the main program interruption began stopwatch time. 2, curl_setopt Subroutine