系统要求的时间准确程度,如果要求不高,如,30秒/年,大可以直接用单片机+显示直接完成 在单片机内编一个小程序就可以-System requirements of the accuracy of the time, if the requirements are not high, such as 30 seconds/year, can be directly used to directly complete the MCU+ display in the single chip can