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Pac-Man Genome Project

Annotated disassembly of old arcade ROMs in the name of history
  [vote for,

Many years ago, there were video games in arcades which are now considered classics, with their place in history. As hardware deteriorates, hobbyists have taken to preserving the ROM images of these games for posterity, and writing emulators for the ancient hardware on which they ran; therefore now those who own the original machine (or lie about doing so) can download the ROM images of many old arcade games and play them on their home PCs, perfectly emulated.

Many of the older games were, for their simplicity, wonders of engineering. In a handful of kilobytes, the programmers managed to implement the entire game, in a way that ran on the limited hardware of the time. The games were often hand-coded in assembly language, using tricks that are all but lost save to the most obsessive; interleaved instructions, self-modifying code and more; quite a feat.

Not too long ago, amateur computer historians took other machine language programs of note (the original Microsoft BASIC being one), disassembled them by hand, and posted carefully annotated disassemblies online, noting the various interesting features.

I was thinking that the old computer games (such as classic arcade games) would be excellent candidates for such analysis, because of:

a) their historical significance,

b) the aforementioned tightness of the code and hackerly tricks,

c) the unique hardware they ran on. (Some used custom multi-CPU arrangements, for example, with two different 8-bit CPUs handling different tasks. That could be one of the interesting features to look for.)

acb, Feb 02 2002

mame.dk arcade ROM repository http://www.mame.dk/
This site has arcade ROMs. (For legitimate owners of arcade machines, of course.) [acb, Feb 02 2002, last modified Oct 04 2004]

Atari Games Prototype Museum http://www.safestuff.com/
Lots of info, designs, etc on the making of various Atari games, incl. Star Wars, Battlezone [pottedstu, Feb 03 2002, last modified Oct 04 2004]

More Atari design documents http://www.willowsp.u-net.com/andy/atari/
More indepth and technical than the above; shame PacMan was by Namco, who probably keep all this sort of thing very well locked up. [pottedstu, Feb 03 2002, last modified Oct 04 2004]

Disassembly of bootleg Ms. Pac-Man http://www.cis.rit....ngo/mspac/mspac.asm
disassembly of the "bootleg" version of Ms. Pac-Man [nerfboy, Oct 04 2004]

Disassembly of Pac-man http://cubeman.vg-n...e-source/pacman.asm
[nerfboy, Oct 04 2004]

Disassembly of Ms. Pac-man http://cubeman.vg-n...de-source/mspac.asm
[nerfboy, Oct 04 2004]

Disassembly of Gameboy Tetris http://www.devrs.com/gb/files/tettab.zip
see http://www.devrs.com/gb/files/doxs.html for details. [nerfboy, Oct 04 2004]


       Namco would probably object pretty strenuously to this; you need to wait till they go bankrupt.   

       During and after Atari's long slow demise, a lot of documents have come out explaining how *their* games were designed and produced. I've linked to a couple of sites. The second one is better and has lots of amazing technical information, like specs for the Gauntlet machine. Not quite on the level of a disassembly, but pretty low-level.
pottedstu, Feb 03 2002

       Re: Namco (or other owners) objecting: I don't see how this would be more objectionable to them than making playable ROMs available on mame.dk. You can't play an annotated disassembly, it has little resale value, and it isn't exactly a trade secret (after all, it's not like they'll suddenly have to compete against all the 6502 wizards who honed their skills looking at 20-year-old assembly code).
acb, Feb 04 2002

       I don't think Namco are keen on ROMs either, especially as PacMan and all that surrounds him is a trademark still with some considerable value.
pottedstu, Feb 04 2002

       In either case, the ROMs are already out there for the downloading. Namco and others have been somewhat lazy about stomping on them, and it's unlikely that they'd prosecute an annotated disassembly any more vigorously.
acb, Feb 05 2002

       Churn, churn, churn...   

       I thought you were going to breed Pac-men or something. Bun anyway.
dbmag9, Jan 18 2006

       // In a handful of kilobytes, the programmers managed to implement the entire game, //   

       Ah, those were the days. Several decades ago, I hand-coded a game in just under 1K of machine code, for the ZX81 (sans wobbly expansion pack). It wasn't a very good game (total sales: 12; overall earnings: about 1p per hour), but then again it wasn't a very bad game either.
MaxwellBuchanan, Jan 21 2015

       Well, [bigs], these early experiences with computers have clearly made us the happy, wealthy people we are today.
MaxwellBuchanan, Jan 22 2015

       I was thinking about the ancient Apple II games. Chiefly because I downloaded Bouncy Ninja to the iPAD which looks exactly like something which might have come out in 1980.   

       But simple games like Flappy Bird and 8 bit music are in vogue. I wonder if there would be a market for the awesomest of Apple games for mobile devices?
bungston, Jan 24 2015

       The reuse of the same routines and functions for multiple games created by one programmer or game studio is similar to the evolution of genetic material.   

       It would be neat to catalogue the ROM images of all the games that were ever made for one particular console and then to perform informatics analyses on the database.
Cuit_au_Four, Jan 24 2015


       Well then maybe that idea would work better for images of DOS or Atari executables.
Cuit_au_Four, Jan 24 2015


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