Long time without news, I'm sorry!
But now i'm fully ready to begin the development of my swarm of iRobots!
Today I will talk about the cheap RF transceivers I found at sparkfun (http://www.sparkfun.com/products/9582).
They are FM transceiver with configurable frequency bandwitch, SPI interface, internal FIFO (very small, but very useful). Right now I'm programming the eLua software to test them:
Here I'm using the STM32 kit to talk with two RFM12 (one on each SPI port) they will simply echo each other as a test application.
I will create soon a GITHub Repo to share the code of this post and futures ones!