A E1.20 RDM decoder based on DMX512 decoder.
It was made for DSview but I don't see why it would not be compatible with Sigrok (untested).
Just copy the dmx512-rdm folder to your "C:\Program Files\DSView\decoders" folder, open DSview and select it from the decoder tab.
It's still a work in progress but so far this works :
- Decoding default PID code and name
- Decoding manufracturer name