[Coladam] VDP upgrade?

[Geoff Oltmans]

This may have been done already, but I figured I'd ask.

While hunting around for info on the Yamaha V9938/9958 VDPs, I stumbled 
across information talking about the Sega SG-1000 and Sega Master 
System. The SG-1000 uses the same hardware that the ColecoVision uses 
(same sound chip, same vdp, same processor). Then I looked at the SMS, 
which is SG-1000 compatible. Turns out that it's VDP is a derivative of 
the 9918 as well, but with some additional graphics modes (and more 
colors, up to 64) and also a SN76489 sound generator built in (same as 
the CV/Adam uses).

Has anyone ever attempted to interface one of these chips to the Adam as 
an upgrade?