电话智能遥控器主要包括电话振铃检测电路，电话自动摘机和挂机电路，DTMF信号解码电路，语音提示急电路，音频放大电路，以及控制心脏CPU电路-Telephone remote control including smart phones ringing detection circuit, telephone and hang up automatically pick circuit, DTMF signal decoding circuit, urgent voice circuits, au

超声测距,外围用LM567音频解码器来锁定接受的声波频率，程序里用的是40KHZ,发送200ms，然后等待接受进行中断。里面只有程序，外围电路很简单，注意要把信号放大。-Ultrasonic ranging, external LM567 audio decoder to use to lock in acceptable sound wave frequency, the program inside using a 40KHZ, send 200ms, and then waiting fo