Nov 3, 2013
Instead of paying $100 on a SWC (steering wheel control) adapter for my Asteroid stereo I decided to build my own. The end result is running on a teensy usb microcontroller behind the dash, but I prototyped it on an arduino. I've also got the code up on Github for people to check out.
The buttons on a modern Subaru wheel are basic resistor ladders coming out on two separate wires. I just figured out the resistances for each button and set up some key events to feed into the Asteroid.
The resulting package is pretty small. The Teensy is a great micro if you're needing to simulate keyboard or mouse events and need to cram it in a small place.
