G33KatWork
commented
1 year ago Hi BGuiGui,
unfortunately not. There is an open source KNX stack available at https://github.com/thelsing/knx, but this only implements everything above the link layer, so the transceiver is useless with it. So far I only used the board to sniff bus traffic.
I always wanted to try and use the PIOs in the Raspberry Pi RP2040 to implement the KNX Data Link Layer, but I haven't found the time so far. Receiving is relatively easy, because in the end KNX is just a serial port with 9600 baud in an 8e1 config. If you use this transceiver here, you can just hook it up to a UART or implement one in a PIO state machine and you can receive symbols. Transmitting is a bit more complicated as you need to watch the receive line while transmitting and check whether the data that shows up on the bus is actually what you transmitted. If not, you caused a collision and you need to stop transmitting and retry at a later time when the bus is free again. I don't know yet how to implement this with the PIOs, but I also haven't tried yet.
Maybe this helps if you might want to give it a try.
Hello, I'm interested by this project. As you write, STKNX is not a full KNX MAC. It is only a line transceiver. Do you have a software project to Interface shis transceiver with a Knox stack implementation?