VMU Game Uploader

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VMU Game Uploader

Postby Light-Dark on Sat Jun 03, 2017 11:59 pm

Posted this over on DCEmu programming forum but I figured there may be some people here who are interested in this;

I've been working on writing a new game engine for the Dreamcast and so I've looked into putting vmu games onto the vmu through KOS. Couldn't find any good examples out there of how to do so I decided to make my own;

Before you can use this demo you have to do a bit of digging in KOS itself, specifically for the vmufs.c file, on line 750:
nd.hdroff = 1;

Make sure the header offset value is set to 1 instead of 0, otherwise your VMU will say "this game is damaged" when you try to play what you have uploaded. Once you have made sure of this, recompile KOS and you should be able to upload your VMS file to the VMU no problem. I've included Marcus Comstedt's Tiny Tetris within the demo. Hopefully this is helpful.
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Re: VMU Game Uploader

Postby Falco Girgis on Wed Jul 19, 2017 4:09 pm

Jesus Christ, are you SURE you have to recompile all of KOS to do that!? That's absolutely horrible.

That offset is supposed to be 0 for DATA type files, where the header comes first then the data comes next. This is how standard save files work. Then GAME files require the header to be located at the first block, because block 0 is reserved for interrupt service routines and shit. So the layout in VMU flash is:

BLOCK 1: ISR Routines and Shit
BLOCK 2: VMS Header Data
BLOCK 3+: VMU Game Code

If KOS actually has to be recompiled like that, then how is it possible for DC homebrew like Pier Solar to save BOTH GAME and DATA files on a single VMU in a single executable?
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