And yes, these two systems are different. The MegaCD offers a faster version of the MegaDrive main CPU which acts as a co-processor. Furthermore there's some more RAM and an additional graphics chip for ROZ effects and video decoding, I think.
Syncing those things together is the biggest hurdle in MAME/MESS.
Last edited by F-3582; 04/29/09 08:14 AM.