RS485 Modbus master of many slaves devices


If you want to configure the HMI as Modbus master on RS485 to communicate with up to any 125 Modbus slave devices, proceed as follows:

In HMI-Tool

  • Setup a link and choose the right “Link Interface” COM1, COM2, USB,…
  • Select as “Address mode” the “Extended Mode” for RS485 mode.This will let you address many Modbus devices, instead of just one:
  • Once you have extended mode selected, when you will select a tool, the slave ID and the register address can be filled in:
    Here, slave ID=0, register=4×82