基于51单片机，99分钟定时器c语音源码程序。可以通过按键上调下调时间，定时器到时喇叭发声报警 带有点按和连按功能-Based on 51 single-chip, 99 minute timer c voice source program. Time can be raised through the key down timer when the horn sound the alarm with a tap and double-click function