How can I read/edit rom dumps?

Thomas

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Okay so I have some roms that I dumped. How do I play with the code? Can you tell me what software to use or is notepad good enough?

Can you tell what the dump is by just looking at the code?
 
Also what language are the ms. pac roms written in?
 
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Ok... So what software is needed to open the roms the correct way and edit them.
 
Sorry, not my area of expertise. You need to talk to JROK, Spaeth, or one of the programmer types. There are a bunch of people that can tell you, I just do not recall all of the names.
 
The language you're looking at likely depends heavily on what game it is and what part of the rom set it is. Some of them may just have data, some may have actual program on them in some form of assembler written for the main cpu. copy/paste an example, it'd be easier to figure out if we knew what you were looking at.
 
The language you're looking at likely depends heavily on what game it is and what part of the rom set it is. Some of them may just have data, some may have actual program on them in some form of assembler written for the main cpu. copy/paste an example, it'd be easier to figure out if we knew what you were looking at.

Its the PAC6E.532 rom for pacman

I am not sure how to output the code from XVI32 to paste an example yet. I am looking.
 
What language am I looking at?

If you're talking about the program ROMs then you are looking at machine code for the processor it is running on (Z80, 6502, 68000, etc.). You can run it through a disassembler, but if you're not familiar with assembly language programming then it's not going to make much sense to you.
 
If you're talking about the program ROMs then you are looking at machine code for the processor it is running on (Z80, 6502, 68000, etc.). You can run it through a disassembler, but if you're not familiar with assembly language programming then it's not going to make much sense to you.

Matt,

Can you please recommend a disassembler? Its been a while since I looked at assembly language, but would love to do it again.

Also, anyone know how one can then take these and create a .zip file that will run in MAME?
 
All XVI32 does is give you the raw data and allow you to manipulate it. There is no translation/dissassembly/whatever. What you are looking at is machine code if anything...it might be sound or graphics data.

What exactly is it that you want to do? Editing the ROM dump may or may not be the right approach.
 
For 6502 code, Distella is good for disassembly. But it's tailored to the 2600. I'm sure there are better tools for general purpose stuff. And you'll need one that handles the processor in question. For assembly, DASM is a pretty good cross assembler. It is the defacto standard for 2600 programming. Easy to use and powerful.
 
Mr Savage... I dont want to hijack your thread, so if you feel that I am, please let me know and I will take it elsewhere. :)

If I make a change, the CRC changes and MAME no longer reads it. Where does make get the CRC from?
 
Your not Barry... I would love to learn more
 
It would be helpful to know what you would like to modify - assembly code is much more difficult than graphics / mazes / text. Mame in -debug mode has an option to output disassembled code dumps to a file and allows you to watch & modify memory, set breakpoints etc.
 
Your not Barry... I would love to learn more

Cool

It would be helpful to know what you would like to modify - assembly code is much more difficult than graphics / mazes / text. Mame in -debug mode has an option to output disassembled code dumps to a file and allows you to watch & modify memory, set breakpoints etc.

Lets look at a simple example. I want to modify Ms Pac to have different ghost names. Doing that changes the CRC and MAME pukes. How do I get MAME to recognize a "new" version of ms Pac
 
MAME should still run, it'll just complain that the CRC doesn't match. I had some modified Tapper ROMs that had Simpsons characters in it, and while MAME complained, it still ran just fine.
 
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