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Koston

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Hi,

I received my multi and it's working pretty nicely. Load times are very impressive, and at least a cursory test suggests the unit operates flawlessly also when used on an overclocked MVS board (tested 16MHz and 18MHz with Metal Slug).

I was wondering how it works and how to add new games, romhacks 'n such. There's precious little documentation or forum discussion I could find, and The "Roll-Up Pack" by SmokeMonster is not very self-explanatory, so I got a bit curious and took a peek. This is what I found so far (pasted from my notes):

Game ROMs are stored in custom format:

game
├── crom0
├── fpga
├── m1rom
├── prom
├── srom
└── vroma0

The *rom* files are simply concatenated versions of the original
ROM dumps. Only exception is the file 'crom0', which additionally
reorganises the sprite data so that per-block bitplanes are
represented in a linear fashion. In practice, it goes through the
original C-ROM files in pairs and interleaves two bytes from each.

According to the devs, data content itself is untouched except for
Metal Slug X. Checked one game, no modifications.

The 'fpga' file is not related to the original ROM dumps. It
contains nothing but one of the following decimal values:
"10, 11, 12, 13, 14, 15, 16, 20, 26, 30, 45, 65, 76, 130, 131, 141"

The provided 'menu' is also a regular NeoGeo program organised in
same fashion. It contains information of all supported games
(some pulled from MAME sources).

So from this can be assumed that, while reorganising MAME ROM sets into the custom format is trivial, actually loading a custom game isn't. I can only guess what the magic value in 'fpga' file represents, and even if testing each possible (read: previously used) value isn't too much of an effort, only reasonable way to get the menu program to load it would be replacing another game with it, re-using the name etc. which would amount to a dirty hack.

Question then becomes, what are the future plans for the cart software stack? Will the menu, firmware etc. remain closed source? Will there be a method provided for adding new games, or is it intended to be kept walled to "officially supported only"? And so on, <insert more menu modification questions here>

Oh and this is neither urgent or serious - I'm perfectly happy with the product in any case! Just keep on polishing the product and get back to this when you have time.
 
Last edited:
Question then becomes, what are the future plans for the cart software stack? Will the menu, firmware etc. remain closed source?

Will there be a method provided for adding new games, or is it intended to be kept walled to "officially supported only"?
Basically @ekorz nailed it. With the latest FW you have up to 4 homebrew folders for whatever you want. He also provided a link to how to convert games.
 
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