这是一个电子钟微机接口和控制课程设计，能显示分钟和秒，并且能够调整时间。用的是唐都系统中的8255A，8259，8253A -This is an electronic bell computer interface and control of curriculum design, can display minutes and seconds, and can adjust the time. Tangdu using System 8255A, 8259,8253 A