串行口RS485自定义通讯协议，2、功能定义 （1） 监视从机运行状态 （2） 控制从机运行 （3） 读取从机功能码参数 （4） 设置从机功能码参数 3、通信协议方式 PC，PLC 为主机，变频器为从机。采用主机“轮询” , 从机“应答”的点对点的通信方式。轮询可以建立在一个轮询表内，如果是广播发送变频器不用应答。用户可以利用变频器键盘设置变频器的本机地址（默认为00H）。--Custom RS485 serial port communication protocols, 2, function definitions (1) watch from the machine run state (2) control from the machine running (3) reads parameters from machine function code (4) set the parameters from the machine function code 3, communication agreement PC, PLC as the host, converter from the machine. With host " polling" from machine " response" of the point to point communication. Polling in a polling table can be established, if no response is broadcast to send inverter. Users can use the keyboard to set the inverter frequency converter local address (default is 00H).