Re: [Tuxnes-devel] MMC5

[Mike M. <mel...@pc...>]

On Mon, 11 Mar 2002, Byron Stanoszek wrote:

> Can you tell me what the status is of supporting MMC5-style games (I'm assuming
> Castlevania II falls under this category)? I'm thinking about making a 32-bit
> Castlevania II clone as my first project in playing with the Linux port of the
> Playstation 2.

	Castlevania III, actually (Dracula's Curse), was the most famous
example of an MMC5 game. Castlevania II: Simon's Quest is supported in
TuxNES (if your experience differs, please let us know).

> Also, how hard is it to write support for one of these mappers? Can't be too
> bad using source from other NES emulators, no?

	With the proper architecture in place, it's not difficult.
However, MMC5 runs into some limitations with the way the original Nestra
codebase was written in the first place which makes it very difficult, if
not impossible, to implement with the current architecture. The specific
issue has to do with the way the MMC5's registers are mapped to memory
locations below 0x8000 in the NES CPU memory map (Nestra basically
expected them to always be mapped at 0x8000 or higher).

--
	-Mike Melanson