In previous message, Matthew Ballinger said:
> In a message dated 1/30/99 6:19:19 PM Eastern Standard Time, MattBeck writes:
>  I once had my steering wheel mounted cruise control switches fed to PIC then
> to the car stereo and the cruise control. I could control my cruise, volume
> and track functions just by pushing both buttons at once to change function. I
> wired the stereo inputs directly to the switches in the sony cd player. No big
> deal. Now I have a detchable face head unit and would like to do the same
> thing. Before I start reverse engineering the bus used between the face and
> the main unit, I figured I  ask if anyone happens to know a bit about it.
> Protocol? I2C? Parallel? Any feed back would be greatly appriaciated. Thank
> you all.

Sony Rotary Commander (RM-X25) this just 11 switches with resistors:

    15.2K   10K     6.8K    4.7K    3.3K    2.2K    2.2K    2.2K    2.2K  AD
    ___     ___     ___     ___     ___     ___     ___     ___     ___   out
  -|___|-+-|___|-+-|___|-+-|___|-+-|___|-+-|___|-+-|___|-+-|___|-+-|___|-+->
 |       |       |       |       |       |       |       |       |       |
\       \       \       \       \       \       \       \       \       \
 |       |       |       |       |       |       |       |       |       |
 +-------+-------+-------+-------+-------+-------+-------+-------+-------+
                                                                        _|_

--
------------
Yuri Galayda at SIC Vector R&D Department       yura@vector.kharkov.ua
PGP public key available  --  finger yura@vector.kharkov.ua | pgp -kaf