Set DSR pin (serial) on startup

I have a RS232 module that sends a string when the connected buttons are pushed.
But depending on the state of the dsr pin it send that data to one of the two RS232 connections.
without DSR enabled it sends immediate to the relay card without more functionality.
with DSR enabled it goes now to my rs232 of a regular pc with a .net program.
But I want to leave the pc with .net and go to openhab.

I know there is a serial binding and that it is possible to run a rule when the system starts up.
(Not sure witch level I need)
But is it possible to enable the DSR pin in such a rule/script?

Anyone an idea?

I once learned that @Kai made a serial button binding: Serial Button - Bindings | openHAB, not sure if it solves in any way your rs232 issue, but it might show you a fairly basic code which you could try to adopt in your deployment.

is the current version :slight_smile:

Ok not possible then.
Then I have to search for an other appoach.
Pitty I hoped like by home assistant it was possible.