Vision and Modbus communication
Eduardo Margulis
Nov-20th, 2017 6:56

MODBUS enables you to establish master-slave communications between Unitronics PLCs and any connected device that supports the MODBUS protocol. Any controller in the network may function as either master or slave using any of the controller's existing COM Ports.

Unitronics currently supports RTU (binary) transmission mode.

If your controller comprises an Ethernet card, you can use MODBUS IP commands with any connected device that supports the MODBUS protocol

Unitronics currently supports both TCP and UDP Modbus IP protocol.


Within a MODBUS network, you can use standard MODBUS commands to read and write bit and register data; you can also read and write data to Vision controller Data Tables.

Vision PLCs can be configure as either Modbus client -Master- or Modbus -Slave-. it can even be configure as a master slave with the use of two serial ports or two Ethernet Sockets.

Vision enhanced Slave addressing (hexadecimal)

Standart Vision Slave addressing (Decimal)

You can read more information on the VisiLogic help under: Home>Communications>Communication FBs>Modbus and Modbus IP.
You can also access examples on the VisiLogic help menu under examples.

A video tutorial is available on the next links:


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