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RFM12 to Cerberus SPI


[em]Hello world![/em]
I’m planing to connect a RFM12b from (Link hidden -> jeelabs RFM12b) to my FEZ Cerberus. I want to use the 868mhz freq for low energy connection between cerberus and homeautomation.

I’m not 100 % sure if its possible, but so far i have read about it in an other thread. (

Cause I’m not an electronics expert (i know whats U and I… thats it :-[ ), i’d like your support.

My actual problem is:
I don’t know how to wire IRQ and SEL to an SPI Socket (S).
AFAIK SEL means SS and is selection pin. This would mean it needs to conenct to an gpio for programming stuff.
IRQ seems to be some interrupt input signal. So it might also need to be connected to an GPIO

The screenshot shows how far i’ve come with the wiring. Feel free to facepalm whereever you like. Just let me know where it is.

May there is an out of box RFM 868mhz modul out there compatible to Gadgeteer ?



Welcome Michael, nice to virtually meet you.
So item 1 would be to fix the 3v3 connection. You need that, judging by the image of the circuit board.
IRQ needs to be on pin3, since its meant to be an interrupt capable pin.
SDO/SDI are not clear - they might need to be swapped for it to work. MOSI is Master Out, Slave In (you can guess what MISO is :slight_smile: ) but SDO SDI don’t have a reference, is that in and out of the module or the master???