Newer protocols are always fun to explore, such as the automotive CAN bus. Here’s a project by wire2wire which sniffs the CAN signals from steering wheel controls and converts them to a serial output. The main components are a PIC16F876, MCP2515 and MCP2551.
The code and all docs are available in a zip file. Current firmware images include:VW MKV GTI “infotainment bus” 100kbs, raw bus dump (sniffer/snoop), and basic steering wheel button decode. Firmware also has TTL outputs for each of the buttons on the steering wheel. These outputs can be directly interfaced to other devices / inputs without using a PC or another micro. For example you can set up the “phone” button to turn on a light when pressed.
Via Hack a Day.