Open Source Novation Launchkey Firmware
It’s still under development. But you can download the source here and compile it using a free copy of uVision. It also has Eclipse project files to easy code navigation.
My plan is basically to allow remapping of any of the controls to any MIDI CC.
I also want to add a sequencer and an Arpeggiator if I have time.
Let me know what you think in the comments.