当键盘有键按下时，判断键值，启动计数器T0，产生一定频率的脉冲，驱动蜂鸣器，放出乐曲。同时启动定时器T1，显示乐曲播放的时间，并驱动LCD,显示歌曲号及播放时间。

（1） 硬件电路中用P1.0~P1.7控制按键，其中P1.0~P1.3扫描行，P1.4~P1.7扫描列；

（2） 用P2.0~P2.2作为LCD的RS、R/W、E的控制信号；

（3）用P0.0~P0.7作为LCD的D0~D7的控制信号；

（4） 用P3.7口控制蜂鸣器；

（5） 电路为12MHz晶振频率工作，起振电路中C1,C2均为30pf。

-When the keyboard has key press, judge keys, start prearcing counter, produce a certain frequency pulse, drive a buzzer and released music. And the launch of the timer T1, music show broadcast time, and drive LCD, display, and broadcast time songs.

(1) hardware circuit with P1.0 ~ P1.7 control buttons, which P1.0 ~ P1.3 scan line, P1.4 ~ P1.7 scanning column

(2) using P2.0 ~ P2.2 as the LCD RS, R/W, E control signals

(3) use P0.0 ~ P0.7 as LCD D0 ~ D7 control of signal

(4) use P3.7 mouth buzzer control

(5) circuit for 12 MHz crystal frequency work, initial circuit C1, C2 are 30 pf.