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Tri-Force
April 15th, 2002, 21:03
as everyone knows all files can be opened as text. no suprise right. well i was wondering if you open a rom as text and copy the right amonut of the begining (the boot code) is it possiable to copy the boot code to another rom who's boot code isni't supported by an emulator. this is just my theory right now and snice i have no idea which part of the text is the boot code i havn't been able to try it. I ask because if this is able to work then we can hack roms to be able to play in supra or ultra just by changing the code to a known one and using the known ini settings for the new game. can anyone figure this out.

Anton
April 15th, 2002, 21:25
I think it's impossible to boot unsupported roms in this way.
Looks very simple...

flow``
April 15th, 2002, 23:01
you can check out LemAsm (from nemu.com)

it allows you to modify roms, although you might need some knowledge hacking in order to use it.

neoak
April 16th, 2002, 00:55
Practically, is impossible without modify the code. Every rom loads special codes, like compresion codecs (Evangelion64, Perfect Dark and ConquerBFD's MP3, RE2's Bitmaps and MPEGs... etc). You must understand every boot code in order to copy part of it.

(Evangelion doesn't show 2D graphics due to compression and unsupported banks of memory in emus...

The Khan Artist
April 16th, 2002, 07:43
Anyway, why use a text editor? It's much better to do it with a hex editor. Or, you can get Ultra-Edit, and have it all in one. :D

Tri-Force
April 16th, 2002, 08:24
becasue of copy and paste

Tri-Force
April 16th, 2002, 08:25
I dont know it just makes me think of that scene from the Matrox where the dude is watching the code on the screen but what he sees in his mind is red head brunete becasue he knows the code that well.

Cyberman
April 17th, 2002, 02:56
Originally posted by Tri-Force
I dont know it just makes me think of that scene from the Matrox where the dude is watching the code on the screen but what he sees in his mind is red head brunete becasue he knows the code that well.
Ummm.. I don't believe that's what they said..
Actually they were programed so well from the nerological data and information sent to them that's what they saw.

Now back to the subject.

Text editors are extremely limited first off.
Text is generally ASCII data which is from 0-127 this is kind of limited.

A hex editor is better suited for binary data (IE ROM CODE).

Cutting and pasting boot code though probably thought of won't work. Not only because the boot code is different for each game but what each game uses for a library of software is different.

The only thing I can think of is dissasembling and decompiling the entire code in the ROM. Using HLE to pick off Chunks of code you know are likely to be calls to library functions. Then reversing the entire rom painstakingly.

Cyb

icepir8
April 22nd, 2002, 20:17
Hex Workshop v3.11 lets you cut/copy and paste. Also you can have multiple files open. No you can't just copy a new boot code into a rom and have it work. The newer roms check the boot code version in several differrent places to make it harder to modify and of the code. Also the CRCs in the header would need recreated.

L8r,

Icepir8

norwaynoob
June 2nd, 2005, 06:27
I think it's impossible to boot unsupported roms in this way.
Looks very simple...
Heheh, yeah. Too simple to be possible.