'96 DIS Interface

[graynada]

A bit of a long shot, and I may be in the wrong section but does anyone know what the protcol is for the OEM radio to DIS for a '96 A8?

I have replaced the OEM radio with an Empeg unit and so no longer get the ICE readout on the top section of the DIS. The connctions are available at the radio end and armed with my self taught PIC programming skills I though I might be able to make use of this now blank top section for my own use, eg accurate electronic speedo. I don't have an oscilloscope so I wondered if anyone knew waht the OEM readio transmits over the DIS? Is it just ASCII RS232, or is it it's own Audi format?