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sonic 1,2,3 + knuckles roms
Closed (accepted) by: root.
coraz » 2015-06-28 19:58:59

I have reverted the physical status of the 3 s+k roms based on sonic wikia

the wikia states that the games should have specific features, and details these features
for example in sonic 3 & knuckles, super sonic can breath under water & has a new move called hyper flash

I checked out the combined roms on the mess emulator and these features are not there (I can make a video if you don't trust me)

super sonic can't breath underwater nor has that new move

so either the emulation is bad or the roms are missing something
right now we should not presume these roms are proper as some features are missing

let me know what you think about it
coraz » 2015-06-28 21:46:31

after more tests i must say i was mistaken, the hyper sonic feature is actually there, I have unlocked it with the debug menu rather than through regular gameplay and it is just as described by the wiki, i guess the hyper sonic & super sonic are not unlocked the same way

in this case i'm just going to revert them back to physical=1 since now there is no more reason to think anything is missing

gomenasai ^^
andlabs » 2015-07-01 15:45:50

Honestly I think the ROMs should be deleted outright, or kept but marked as some way to show that they're constructed, rather than a standalone physical release. The ROMs mainly exist to allow them to be played in emulators, which don't emulate the Lock-On Technology hardware of the Sonic & Knuckles cart. They are what the MD would see after the hardware has done the work of merging the games.

What we should really be doing is including a dump of the UPROM region (I think that's what it's called, but I don't quite remember) that provides the programming that tells the S&K cart how to create Knuckles in Sonic 2... This is a separate chip.

Just my opinion.
coraz » 2015-07-02 17:04:03

I understand your point but what you say could also apply for many roms of the NES, SNES, MD/GEN and likely other systems

these sets have tons of merged roms images, while the physical carts would have multiple roms chips which are merged by the cartridge hardware

no-intro is not a project entirely dedicated to emulation accuracy, it's more leaning toward having good dumps playable is popular emulators, if you keep that in mind, then these roms aren't illegitimate
einstein95 » 2015-07-03 01:35:26

Okay, after using MESS to dump the emulated cart region, I've found a few things:
Sonic & Knuckles + Sonic the Hedgehog (World): This is only Sonic & Knuckles and Sonic the Hedgehog (World), no patch region.
Sonic & Knuckles + Sonic the Hedgehog 2 (World): Sonic & Knuckles, Sonic the Hedgehog 2 (World) (Rev. A) and the patch region.
Sonic & Knuckles + Sonic the Hedgehog 3 (World): Sonic & Knuckles, Sonic the Hedgehog 3 (USA), the patch region and additional garbage data.

So for accuracy, here's what I suggest:
Apply patch rom at 0x300000 (preceding blank space filled with nulls) for S&K + Sonic 1
Delete the garbage data starting at 0x340000 for S&K + Sonic 3

This would ensure that the only difference is what ROM is included and that all data from the Sonic & Knuckles cart is still present.