We've built some nodes using this example. I think more people did and probably most common sensors that fit inside the memory have already been connected to it by someone. A version with a DS18B20 works and we're looking for other sensors to connect. The HTU21 shown in the example is next. Surprisingly there are hardly any ready to use sketches around.
This combination pro mini/rfm seems to be the cheapest possible node useful for relatively simple use cases. I think many less complex use cases get stuck on the still high price tag of available nodes. So ultimately I aim at making some pcb's that could result in a working node with a price tag of a little over 12,50 (not counting the batteries and casing). But that's something for a different topic.
To support that I'd like to build and share a library with ready to use sketches for as much sensors as possible. Does someone has something to share?
