If you are reading this I suppose you are already familiar with GMLAN. In short, GMLAN is a communication protocol based on CAN-BUS to send data between different Electronic Control Units (ECUs) in the car like BCM (Body Control Module), IPC (Instrument Panel Cluster), EHU (Entertainment Head Unit) and so on. GMLAN is a single-wire CANBUS protocol (SWCAN) with 33.3kbps baudrate.
The only thing I wanted was to sniff steering wheel radio commands and send them to control my CarPC, but this turned out very interesting for me to think of other possibilities and ways to make my car smarter.
One main thing I wanted was buttons from the factory radio to work with Kodi (XBMC). I will also have steering wheel controls, but working radio buttons is damn cool!
I had some ideas in my head. I started with what I had – Raspberry Pi. It has GPIO pins. You can use them to interface buttons with your software, like Kodi. And that was one approach. One other idea that clicked in my head was – keyboard controller. It has 100+ key commands you can use, it’s dead simple to interface with Raspberry Pi – via USB, it’s also very easy to set them to work with XBMC, just edit the keymaps. Also, the best thing – GPIO pins will remain free for other modules.
From April 2015, since I own this car, I wanted to have a better in-car-entertainment (ICE) system. My Opel Corsa D from 2009 started life as one of the most-basic models, called Essentia in Europe or Life in UK. From factory it comes with basic plastic steering wheel with no radio controls, BID screen, CD30 (no MP3) and only 4 front speakers in front. This is actual photo of my Corsa D, with leather steering wheel with radio controls I installed week ago. I love it. Everything else on this photo is stock.
There is no centre speaker and no rear speakers. First thing was modifying my CD30 (Delphi-Grundig) amp and add an AUX input cable. I couldn’t find the schematic on the internet, so I figured out I could insert analog audio signal directly in the power-amp. And yeah, it worked. With a good source (like high quality smartphone), it’s sounds great.
But, I needed something better. And I found the answer – CarPC (Carputer, Car Computer – whatever).