I would like to share a code to use a quadcopter transmitter with an arduino. In fact, v2XX quadcopters family share the same transmitter protocol with a 2.4G nrf24L01 compatible chip. I have found the explanation of this hacked protocol (https://bitbucket.org/rivig/v202/src) thanks to rivig.
So I implemented a receiver in an arduino. Slo now I can remote control my arduino projects with this transmitter. My code is not well tested and not reliable, there are many improvments to do. So don't use it with RC model, it can hurt someone.
Page project : http://www.wavecruncher.net/~execuc/projects/pv202_receiver/ Source code : https://github.com/execuc/v202-receiver