用定时器T1方式1来产生歌谱中各音符对应频率的方波，由P1.0输出驱动喇叭。 节拍控制可通过调用延时子程序次数来实现。- Timer T1 mode to produce the various notes in the song sheet corresponds to the frequency of square wave, driven by the P1.0 output speaker. Beat control can be achieved by the numbe