采用DS1302+89C52的电子钟控定时打铃系统，可以控制1~10个电铃，适合于单位使用，并可设定节假日不打铃。-Used DS1302+ 89C52 electronic beat bell clock timing system can control 1 ~ 10 bells, suitable for use in the unit, and may not play the bell set holidays.