With the RFM12B becoming a nice low-cost option for low-volume wireless communication, and the RF12 library proving to be a solid software driver for it, it’s time to generalize a bit further…
Say hello to the new RFM12B Board:
This board adds a voltage regulator and 3.3V/5V level conversions, to be able to use the RFM12B on 5V systems such as the various Arduino’s out there, the RBBB, … anything you want, really.
There are 8 pins on this board, of which the 8th is a regulated 3.3V supply which can be used in other parts of the circuit – the voltage regulator will be able to supply at least 100 mA extra on that supply pin.
The other 7 pins are:
- SPI clock (SCK) – Arduino digital 13
- SPI data out (SDO) – Arduino digital 12
- SPI data in (SDI) – Arduino digital 11
- SPI select (SEL) – Arduino digital 10
- IRQ – Arduino digital 2
Just hook each of those up to an Arduino, and you can use the RF12 library as is!
With an 8-pin stacking header and a bit of bending, cutting, and soldering two wires (I used a jumper wire, cut in half), you can even stick this thing right onto an Arduino:
But of course using a normal solderless breadboard and some wire jumpers will work just as well.
Note that this board can also be tied to 3.3V systems – just use the bare PCB (and short out three solder jumpers), which then becomes a breakout board for the RFM12B. No need to mess with the 2.0 mm pin/pad distance on the RFM12B module itself.