Aim: read Modbus RTU RS485 Data from Sensor System: OH3.2 (openHABian - Hassle-free openHAB Setup) Binding: Modbus-Binding (3.2 stable) Device: RPI USB RS485 Raspberry Pi - USB-RS485-Schnittstelle, CH340C [RPI USB RS485: Raspberry Pi - USB-RS485-Schnittstelle, CH340C info for Device Hello, I …

[image] Hoelli: Could not connect to endpoint ModbusSerialSlaveEndpoint [getPortName()=/dev/ttyUSB1] – aborting request Not sure what’s under the red blob in your permissions screenshot, but runtime user is openhab

thx for your reply! so you mean that my change of the (standard) username “openhabian” to another could be the problem?

No idea what you’ve done. The user that is running the openhab service needs permission to access the serial port. openhabian/console users are unrelated to this. (openhabian is a setting up tool, openhab is the actual product here)

how can I find out what is the “user that is running openhab” - can you explain me, please! I changed my user, at the beginning…: [image] should I rename (hostname) it to “openhabian” as it was in the beginning?

[image] Hoelli: I changed my user, at the beginning…: Changing Linux user is a bad idea unless you know all the implications on openHAB(ian) - which you apparently don’t -, and not of any or just of negligible benefit anyway. You should change the user back but I’d rather suggest you reinsta…

Thanks alot for reply! Sry I’dont understand. Maybe I wrote something wrong above - I think have only changed the hostname - is that also a “bad idea” (in sudo openhabian config)?!: [image] [image] how can I find out my current linux-user…?

Smartanemo is a host - name of the computer/system. openhabian is your user @all, he did not changed the user. This is the default user on openhabian installed system. Mine is the same.

Modbus RPI USB RS485 RPI CH340C Device doesn't work - Error connecting

Add-ons Bindings

rossko57 (Rossko57) February 3, 2022, 7:03pm 6

I don’t think that matters to openhab software, it’s probably still running under user ‘openhab’?

re - The user 'openhab' is aleady a member of 'dialout'
That looks promising.

This might help -