由于RS232的电平与Arduino Mega 2560的接口电平不能兼容，所以就需要进行电平的转换，即进行串口转换模块的设计，本文选择利用ATMEGA16U2-MU模块来做电平转换，将上位机的指令通过此模块发给下位机-Since the RS232 level is not compatible with the Arduino Mega 2560 interface level, so we need to level conversion, that is designed to serial converter module, the paper choose to use ATMEGA16U2-MU do the level conversion module, the host computer this module instruction issued by the next crew