时间是现代社会中不可缺少的一项参数,无论是平时生活还是社会生产都需要对 时间进行控制,有的场合对其精确性还有很高的要求.采用单片机进行计时-Time is indispensable to modern society of the parameters, whether living or social production are usually required to control the time, and some occasions, there is a high demand