>
> How differently does the V-Int work on this system? In STH, the "main" code section
> stays waiting for a flag that the V-Int should set in RAM, and only then follows with
> the rest of the execution (processing objects, the scroll engine..). V-Int is
> triggered at either 60 or 50 times per second (or more clearly, when it's about to
> work on a frame), and it requires a special flag to be set within VDP, and the SR
> register set to a specific value...
>
the Vint isn't tied to the VDP, it seems to be once every 1/60th of a second all the same tho, you just can't enable/disable it with the VDP registers.
> And finally, how different the color system is? Graphics keep being 4bpp but
> supporting more color tones? Or is it improved the "good" way and maybe give more
> color depth? segac2.cpp seems a bit confusing to me yet :P
>
you have more colour tones (it's 5bits for each pen instead of 3), and IIRC separate palettes for sprites/bgs. There's also some colour banking involving the protection, but you can mostly ignore it for your own development. Basically everything is the same as far as the video goes (it's the same VDP) it just ignores the internal CRAM and uses the external Palette RAM.
> I haven't gone much further with the MegaPlay yet; I don't know the Z80 instruction
> set too well yet, I have merely edited the description ROM with a hex editor so the
> strings look appealing to my game, and I only got to build my custom ROM just
> yesterday before going to sleep.
> But, overall, the specially the C2, seems like a much better approach than the
> MegaPlay, but the lack of Z80 is my only drawback. I don't know if keeping everything
> at 68k side is going to make my game a bit slower, but everything else seems like
> great improvements. Anybody has a different opinion in this regard? What are your
> reasons?
I'd suggest you optimize your code better, even a complex sound driver shouldn't be eating too much time up on a 68k.
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