Originally Posted by
Sik
That reminds me of a discussion I had earlier today.
One of the issues with the SVP is that, erm, Virtua Racing cost $100 when the game itself wasn't worth that price. So the discussion went around why not make the SVP a standalone add-on and games plug on top of it? (instead of the whole 32X) The problem: SVP runs directly off the game ROM, stealing cycles while the 68000 isn't touching it (hence it requires a fast ROM, which probably added to the $100 price tag). But if you want to use slower ROMs, you can't make the SVP stop the 68000, since in the usual area the Mega Drive is in control of timing, you'd need to force the 68000 into a separate area to halt it when needed, which by the way is too small so it needs bank switching to allow access to the full 4MB… which is what the 32X does. And you'd probably need to run the SVP off RAM since the ROM would be too slow for it… which again, is what the 32X does for the SH2s (which have their own 256KB of RAM). And ROM accesses are pretty slow for it (even moreso if the 68000 is running off it instead of work RAM). And all that mess is the whole source of programming issues with the 32X (well, there are other problems, but they're minor when compared to that).
The 32X is a clusterfuck to program but what led to the engineering decisions that caused most of that mess in the first place actually came from the base system itself, and a SVP add-on would also suffer from it. The only reasonable workaround would have been instead to use what the SVP already did, but forcing it to run exclusively from RAM (no ROM access) and have the 68000 spoonfeed it the data it needs. Then at least you'd be able to use the SVP with slow ROM accesses, which should have lowered the costs. And I wonder if the 32X could have benefited if it had taken the same approach too. Oh well.
Sorry for the off-topic, lol