@tekka Thank you very much! I was able to build a simple sensor I will test it soon and report back.

@tekka Thank you again :) It works! I made a custom board with STM32L073RZ and tested it with MySensor over my RS485 network. As a first step I made only a simple sensor with one digital input now I start to write a sophistacated raditaor valve controller with MySenesors library :)