SGB Bootrom dumped by costis

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SGB Bootrom dumped by costis
by Lord Nightmare on 2009-09-17 (#50698)
see http://www.its.caltech.edu/~costis/sgb_hack/ for details

LN

by Dwedit on 2009-09-17 (#50700)
Sweet, anyone going to do the GBC or GBA in GBC mode?

I see this one cuts straight to the chase and immediately displays the Nintendo Logo, then exits. No 4 second wait.

by caitsith2 on 2009-09-19 (#50726)
Not only that, this boot rom does NOT validate the logo NOR the header.

It is the snes that does that. If the snes side bios was to be patched to always run, then any logo could be used there.

by Dwedit on 2009-09-19 (#50730)
From what I saw on Youtube, the GB's Nintendo logo isn't actually on the screen when the games start. It plays a SNES logo, then starts the game.

by tepples on 2009-09-19 (#50732)
Most Game Boy games blank the screen as soon as they get control of the CPU. Wordtris, on the other hand, scrolls the Nintendo logo off the bottom. So if you start Wordtris on a Super Game Boy, you see the Super Game Boy intro, and then you catch a glimpse of the Game Boy's Nintendo logo before it falls out of view. Want me to put a video of this on YouTube if I can find my equipment?

by byuu on 2009-09-28 (#50875)
caitsith2 wrote:
Not only that, this boot rom does NOT validate the logo NOR the header.

It is the snes that does that. If the snes side bios was to be patched to always run, then any logo could be used there.


That is correct. What's interesting is that the logo data is displayed no matter what, but the SNES BIOS only proceeds to play the game when the bootup code matches what's cached inside the BIOS.

The main thing this 256-byte boot ROM does is send six packet commands to the SGB BIOS which contain the bootup code.

by Dwedit on 2009-09-28 (#50886)
In case someone missed the GBC getting dumped:

http://www.fpgb.org/?page_id=17