通过控制定时器的定时时间来产生不同频率的方法，驱动喇叭发出不同音阶的声音，再利用延时来控制发音时间的长短，即可控制音调中的节拍。把乐谱中的音符和相应的节拍变换为定时常数和延时常数，作为数据表格存放在存储器中。由查表程序的到定时常数和延时常数，当延时时间到，再查看下一个音符的定时常数和延时常数。依次下去，就可以播放一首完整的歌。-Timer by controlling the timing of time to produce different frequencies of ways, drive the sound speakers make different scales, re-use delay to control the pronunciation of the length of time, you can control the tone of the beat. A musical score in the notes and the corresponding transformed into regular rhythm constant and delay constants, as the data tables stored in memory. By a table look-up procedure to the timing constant and time delay constant, when the delay time to, and then see the next note of the timing constant and delay constants. Turn down, you can play a complete song.