shuzhizhong

说明：  课程设计,数字钟的电子技术课程设计.数字钟是一种用数字电路技术实现时、分、秒计时的装置，与机械式时钟相比具有更高的准确性和直观性，且无机械装置，具有更更长的使用寿命，因此得到了广泛的使用。
(Curriculum design, digital clock electronic technology curriculum design. Digital Clock is a digital circuit technology with hour, minute, second timing devices, and mechanical clock, compared with higher accuracy and intuitive, and no mechanical devices with more longer life, it has been widely used.)