Hardware

• Raspberry Pi B xy as the Modbus master
• CODESYS Control Win V3 as the Modbus slave

Requirements for the Modbus master

• Create a "standard project" and select "CODESYS Control for Raspberry Pi SL" as the device.
• Define the target system via Network search.
  
  
  
  
• Insert an Ethernet adapter, a Modbus_TCP_Master and a Modbus_TCP_Slave in the device tree.
  
  
  
  
• Adapt the "PLC_PRG" as follows:
  
  

Requirements for the Modbus slave

• Create a "standard project" and select "CODESYS Control Win V3" as the device.
• Define the target system via Network search (see Modbus master).
• Insert an Ethernet adapter and a Modbus_TCP_Slave_Device in the device tree.
  
  

Setting on the Ethernet adapter (master and slave)

• Determine which interface is to be used.
  
  

Setting on the Modbus_TCP_Slave (master)

Tab 'General'

• Enter the IP address of the slave device (in this case the CODESYS Control Win V3)
• Issue a unique ID for the Modbus configuration
  
  
  
  

Tab 'Channel'

• Create an input register (counter that is sent by the Modbus slave device) – cyclic update every 100 ms.
  
  
  
  
• Create an output register for writing your own counter.
  
  
  
  

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I/O mapping

• Assign input and output variables.
  
  

Settings on the Modbus_TCP_Slave_Device (slave)

Tab 'General'

• Activate monitoring of the communication.

Tab 'I/O mapping'

• Assign input and output variables.

Downloading and starting the projects

Master

• Load the application to the controller.
  
  

Slave

• Load the application to the controller