在beaglebone black上通过按键检测，调整pwm输出波形，使用与电机调速-In beaglebone black by key detection, adjust pwm output waveform, use and motor speed

ds2781系列包括2784 2740，用宏进行选择。 onewire（但总线）协议调试。本文件是atmelstudio完整的工程，芯片时atmge256rfr2，请自己选择修改即可。另外请根据时间时钟进行调整延时-ds2781 series includes 27,842,740, macro selection. onewire (but bus) protocol debugging. This document is atmelstudio complete engineering,