That was the problem! I didn't add the command to the CODESYSControl_User.cfg, only CODESYSControl.cfg.
Thank you!

Hello and thank you for your quick responses! "were the COM_Master_ModBus port and the COM_ModBus_Slave port already working?" ---- No they were not. I've attached the system info and some other screenshot, maybe they help. If someone else reads this and also has troubles finding the "...

Hello! I'm trying to set up a connection between a pyrometer and my RevPi Connect via ModBus RTU in Codesys. I followed this tutorial https://revolutionpi.de/tutorials/beispiel-modbustcp-rtu-master-2/. I would like to use the RS-485 port if possible. My problem is when starting the application the M...