单片机产生音乐源码及上频谱转码工具。 单片机通过控制引脚的高低电平来产生频率，接着再控制输出频率时间就可产生美妙的音乐。-SCM source code and produce music spectrum transcoding tool. Microcontroller to generate a frequency by controlling the pin high and low, and then again to control the output frequency