MODBUS通讯协议标准详细说明，中文版本。(Modbus is a serial communications protocol originally published by Modicon (now Schneider Electric) in 1979 for use with its programmable logic controllers (PLCs). Modbus has become a factory standard communication protocol and

基于SECS(I)串口通讯的 SECS通讯协议，主要介绍SECS（1） SECS（II）(SECS communication protocol based on SECS (I) serial port communication)