IoT Protocol -- Modbus
  2021-02-20.
  Category & Tags: 
  
    
  
    
      
        IoT, 
        Modbus, 
        RS232, 
        RS485, 
        RS422, 
        Serial, 
        COM, 
        CAN1939, 
        MQTT, 
        Emulator, 
        Simulator
    
  
    OSI vs. Modbus Layers: Tip: RS-485/RS485’s new name is EIA-485. UART usually (99%) means TTL in shops, not 232/485. DB9 physical port usually (90%) means 232 electrical signals level standards. Modbus Protocol # See Also: 【strongly recommend!】 a nice intro to Modbus and Modbus Enron. (Simply Modbus 软件收费,但是这个 Modbus 入门文档非常好) 一文看懂 Modbus 协议 Complete Modbus Guide. a good intro to Modbus. Each Modbus Slave has 4 tables with 9999 values in each table. ...