Modbus RTU

Estimated reading time: 1 minute

Refer to these sections for details:

Supported Series

Modbus RTU Controller

Websitehttp://www.modbus.org/

PLC Connection Settings

Parameters Recommended Options
PLC Type Modbus RTU
PLC Interface RS485 RS232/RS485
Baud Rate 9600 9600 ~ 115200 
Data Bits 8 7, 8
Parity Even Even, Odd, None
Stop Bits 1 1, 2
PLC Station # 1 0 ~ 255

PLC Configuration

The steps shown here are for the Modbus RTU PLC.

Broadcast Command: Yes

Extend Address Mode: Yes

Communication Mode: Modbus RTU protocol

OT Link Platform DeviceHub Configuration

To configure DeviceHub for this Modbus RTU PLC:

  1. DeviceHub > Add Device
    Type: Modbus
    Driver: Modbus RTU

  2. Enter details specific to your environment and click Add Device.

Device Addresses

Data Type

Device Type

Format

Range

Description

Bit D DDDD 1 ~ 9999 Discrete Input Contacts
Bit C DDDD 1 ~ 9999 Discrete Output Coils
Bit H_Bit DDDDdd 1 ~ 999915 Analog Output Holding Registers
Bit I_Bit DDDDdd 1 ~ 999915 Analog Input Holding Registers
Int H DDDD 1 ~ 9999 Analog Output Holding Registers
Int I DDDD 1 ~ 9999 Analog Input Registers
Float H_Float DDDD 1 ~ 9998 Analog Output Holding Registers
Float I_Float DDDD 1 ~ 9998 Analog Input Registers