> > Is this the type of thing that makes Konami such devious hardware designers?
>
> Generally what makes them devious is that all of their custom chips are *extremely*
> flexible. The K056832 has 16 physical VRAM pages logically organized in a 2D grid,
> and you can specify for each page of a tilemap which physical VRAM page it is - they
> don't have to be contigious or anything, and in some of the more creative games they
> aren't :-) No other hardware is that flexible, including ST-V.
>
the whole physical page / logical page concept is very segaish anyway, system16 does it, and IIRC the Roz layers on ST-V are pretty insane in that way.
> > * Maybe one way to handle this is to have two seperate memory maps and switch
> between
> > them based on bit 0002 and 0020? Gonna' look to see if that's possible...
>
> In this case, you're best off just defining each of the ranges (6000-6fff, 7000-7fff,
> 8000-fbff) as a READ32_HANDLER/WRITE32_HANDLER and auto_malloc()'ing the necessary
> RAM space. (MESS does it in cases like the Apple Lisa where there's a custom MMU
> (original Apple VLSI, not the PMMU Motorola sold for the 680x0) between the 68k and
> the bus and so nothing has a fixed physical address, and Sega System 16/18 are also
> similar :-)
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