I already made by using the "LEGO Power Functions IR Library" to create an IR transmitter which is sending PWM to the original lego receivers on both chanels, so that i am able to speed and steer proportional within the 7 steps the power functions protocol is able to handle. (http://www.philohome.com/pf/LEGO_Power_Functions_RC_v120.pdf)
Next part of my project will be to replace the original receiver by an arduino. It should be possible to control it by my custom sender as noted above AND by the original lego senders. This should enable me to operate with cheap and small comon rc servos.
And here is the point I am stuck.
The above lib only has sender functionality. Does anyone know a lib which can receive and decode lego pf ir protocol?
I played around with IRRemote but i do not understand how to get the ir packet (everything between start and stop bit). How do I define what is a low bit, high bit and start / stop bit?
I think when I have 1 packet of pf protocol as output i think i am capable of parsing the protocol by myself, but i don't know how to get it.
Your help is really appreciated ;-)