decode the LEGO power functions protocol

[maelli01 74]

LEGO power functions is a system of electronic components, motors,

lights, remote controls to power various LEGO models.

The remote control works with IR, but works surprisingly well even

when there is no direct visual contact. The handheld unit is small,

has two joystick-buttons, and allows 4 different channels to be selected.

Much cooler than a TV remote!

 

Interesting for hacking, LEGO has made the protocol open source, so 

anybody can play with it, as long as not making it commercial.

The protocol can be found here:

http://powerfunctions.lego.com/en-us/ElementSpecs/8884.aspx

 

So I decoded the powerfuctions protocol with the launchpad/energia:

 

Apart from the lauchpad, I only needed a IR receiver. I tested with 

a Vishay TSOP38338, other sensors might work as well.

 

The processor sleeps when doing nothing, wake up only when there is 

something to do. It is low power, but not ultra low, since the IR

receiver needs around 0.4mA.

 

//example program f

[bluehash 1,581]

@@maelli01 Thank you for sharing!