Post #11000. =P So as some of you may or may not remember, I am the owner of this: http://i86.photobucket.com/albums/k103/Overlord44/12-in-1-pirate.jpg (bigger) Which amongst other gems, has this: Anyway, my Retrode arrived today, and I've been playing around with it by dumping some of the carts from the Undumped/Bad Dumps list on Sega Retro, and this cartridge, so let's get to the goods: http://overlord.digibase.ca/dumps/F-22%20Interceptor%20%28USA,%20Europe%29%20%28Sept%201991%29.3C80.%5bdumped%20by%20Overlord%20-%20www.segaretro.org%5d.bin - F-22 Interceptor alternate dump. It appears to be the same as the existing earlier variant ROM, except: As for the pirate ROM: every time I re-detect with Retrode, I get different ROM images. There's a list of what I've pulled out so far at http://overlord.digibase.ca/dumps/yarrr/ - note the 32MBit one was me deliberately forcing the Retrode to dump one that size, so may well be garbage repeating. I've yet to see the Sonic ROM, but I've included after the checksum a few notes for some of them. Hoping some valiant hacker can pull ROMs out of these, I'd like to see that Sonic one =P
Since nobody's replied yet... Does the game work on actual hardware? Perhaps it uses some strange undocumented bank switching that the Retrode firmware doesn't support? It would probably be slow, but it would be nice if there was some kind of direct-access API for the retrode so emulators could be implemented to talk directly to it. This would make it easier to get around any weird copy protection mechanisms because the cart access could be emulated and logged.
It does, but oddly the games it loads aren't any of the ones I've been getting in dumps... it has that weird Sonic 1, the Flintstones, and a few of the others (about 5, iirc). None of the others I've been able to see up to now.
F-22 uses two roms: a 16-bit rom, and an 8-bit rom. The part of the dump that has half the data changing is the 8-bit rom. The rom is on one byte lane and is always the same. The other byte lane will vary according to how the rom is dumped or what model/device is used to dump the cart. This is the same thing you see when you try to look at save ram on carts with save ram. Because the ram is only 8-bit and on one byte lane (the odd byte in the case of save ram), the other byte floats, giving different values.
Many of these pirate carts use custom mappers to make it easy to shove these hacked ROMs in and switch between them without having to rewrite the game code. These mappers work in very hack-y ways.
No idea; this just came up over at SpritesMind, and it is known that at least one version of F-22 is that way. No telling if the ALL are or not. Not without opening them all up.