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Source Code of Several Atari 7800 Games Released 153

Posted by ScuttleMonkey
from the good-way-to-start-an-education dept.
jadoon88 writes to share a series of old Atari 7800 games that have been unofficially open sourced. "Remember Dig Dug or Centipede or Robotron? They used to be favorites when Atari's 7800 series was still around. Since the era of those consoles is over, and a different world of interactive reality gaming has taken over, Atari has unofficially released source code of over 15 games for the coders and enthusiasts to admire the state-of-the-art (because this is what it was back then). During those times, nobody would have imagined in their wildest dreams the games that Atari's developers floated into the gaming thirsty market and instantly swept across continental boundaries. But things changed soon after that and a company once regarded as one of the most successful gaming console manufacturers and developers faded away in the pages of our technology's hall-of-fame."
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Source Code of Several Atari 7800 Games Released

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  • by Anonymous Coward on Friday July 03 2009, @06:29PM (#28575729)

    Whatever the ATARI used for a processor, I don't recognize this ....

    main:
    ;
    ; initialize hardware
    ;
            lda #$7 ;lock in 7800 mode
            sta PTCTRL

            sei ;block interrupts
            cld ;clear decimal mode

            lda #0
            sta OFFSET ;future expansion
            sta PTCTRL ;avoid joystick freeze

            ldx #$FF ;init stack
              txs
    ;
    ; init high score
    ;
            jsr initscore ;clear score to zero
            jsr newhiscore ;clear hi sc

  • Re:Great! (Score:4, Interesting)

    by Acapulco (1289274) on Friday July 03 2009, @06:45PM (#28575831)
    My thoughts too. What does "unofficially released source code means" exactly?

    After some thinking I came to the conclusion that it means you can download the code, but without an open source license applied to it, such that if someone tries to buy the code from them (or the company), they can just stop giving away the files, state that it's still propietary and then still have the ability to sue someone who develops something based on those files. That's the only logical explanation I can come up with.

    Like saying "here, I'll give you my car as a gift" but not transfering the ownership via legal papers. If at some point someone wanted to buy my car I can just tell you "hey, that car I gave you for free....it's no longer yours, it's mine to sell now" and you would have (I presume...IANAL) no legal way of claiming otherwise.

    No?
  • Anyone notice... (Score:1, Interesting)

    by Anonymous Coward on Friday July 03 2009, @06:50PM (#28575855)
    Anyone else notice "ENCRYPTION CRAPOLA -- GO INTO MARIA" comment in main loop of centipede. Love it!
  • Some fun stuff... (Score:5, Interesting)

    by Sprite_tm (1094071) * on Friday July 03 2009, @07:13PM (#28576011)
    * From the devkit readmes:

    2600/7800 DEVELOPMENT KIT<br>
    CARE AND FEEDING INSTRUCTIONS<br>
    [...]
    Feel free to telephone John Feagans at Atari (U.S.) at area  code
    (408)  745-xxxx  any  time you have a question  about  using  the
    software.   He  wrote the download program and the  transfer  rom
    code.   He's the one who did not write any support  documentation
    to go with his software.

    * From the base sw:
    CPX     #1               ;HACK: WE STOP AT 1
    BEQ     SELRTS
    INX                     ;BIGGER HACK: PUSH X INTO RANGE.
    LDA     ZHACKMOD+2,X     ;BIGGEST HACK: TABLE LOOKUP NEXT MODE.

    * Ofcourse, we have explicit words:
    CMP     #$FF                   ;SEE IF ANY INPUT
    BEQ     FUCKYOU
    JMP     GOTOSEL                ;GO TO SELECT MODE
    FUCKYOU   BIT     INPT4                  ;LOOK AT FIRE BUTTON INPUT
    BMI     ATIT4

    LDA     #0                     ;ENOUGH TIME HAS ELAPSED TO ALLOW CAPS
    STA     $1                     ;TO DISCHARGE SO CONTINUE FUCKING WITH
    LDA     #$14                   ;IO HARDWARE

    STA     AUDC0,X         ;GO POUND SAND IN YOUR ASS

    * Citizen Kane anyone?
    LDA     INPT0,Y                ;THESE FOUR LINES MUST BE INCLUDED IN
                                             ;THE FINAL VERSION
    AND     INPT1,Y                ;REMEMBER
    BMI     FUCKBAR                ;REMEMBER,. . ., ROSEBUD

    * In Galaga, at 'a boss hit':
    JSR    ABOSSHIT               ; HOW YOU PRONOUNCE IT IS YOUR OWN
           ;BUSINESS

    * Liek wtf?
    * GROUND TARGET SECRET CODES (SSHHHH!)
    *         0       regular dome           logram
    *         1       regular pyramid        barra
    *         2       detector dome          zolbak (and your mama, too)

    *And finally, an original comment which couldn't be more to the point in 2009:
    *PROGRAMMERS BEWARE: THIS CODE IS OLD AND VERY UGLY! TAMPER AT YOUR OWN RISK

    It looks like Hattrick is written mostly in Forth btw. I personally didn't know they wrote games in that language!
  • Re:Great! (Score:2, Interesting)

    by armanox (826486) <asherewindknight@yahoo.com> on Friday July 03 2009, @07:27PM (#28576117) Homepage Journal
    SCOTUS ruled that what you throw out is public property...
  • Ms. PacMan (Score:5, Interesting)

    by thygate (1590197) on Friday July 03 2009, @07:42PM (#28576209)
    look, it's Ms Pacman

              ;MS RIGHT, HALF OPEN
              DB      $08,$00,$0A,$50,$A5,$54,$25,$D5,$17,$55,$15,$50
              DB      $15,$00,$15,$50,$15,$55,$05,$54,$01,$50,$00,$00

    All the pixelfonts are in there too offcourse. If you're into remaking arcade classics, there's a lot of picture and sound data there just waiting to be recycled.
  • by alnicodon (685283) on Friday July 03 2009, @08:18PM (#28576419)

    I quite like the way this blog [dadhacker.com] by an old time Atari employee recalls the when and how of Atari developement. Something (Donkey Kong port [dadhacker.com] on Atari consoles) that read

    I should explain how Atari's Arcade conversions group worked. Basically, Atari's marketing folks would negotiate a license to ship GameCorp's "Foobar Blaster" on a cartridge for the Atari Home Computer System. That was it. That was the entirety of the deal.

    made it clearer with :

    We got ZERO help from the original developers of the games. No listings, no talking to the engineers, no design documents, nothing.

    but, wait... there was even less:

    In fact, we had to buy our own copy of the arcade machine and simply get good at the game (which was why I was playing it at the hotel our copy of the game hadn't even been delivered yet).

    was for me a sure way to a plentiful of nostalgiaholic reading.

    Al.

  • Re:This is great (Score:1, Interesting)

    by RaymondKurzweil (1506023) on Friday July 03 2009, @08:21PM (#28576449) Journal

    MECC

    Well their logo was quite prominent. The Minnesota Educational Computing Consortium, IIRC. Almost anyone my age in the US remembers things like Number Munchers. Unfortunately "carpet munchers hack" doesn't show up on google.

  • Re:Great! (Score:3, Interesting)

    by Jah-Wren Ryel (80510) on Friday July 03 2009, @08:22PM (#28576455)

    However, did they ever register the copyright for the source code?
    If not, then any damage awards for this "publication" won't amount to a hill of beans.
    Furthermore, who really owns the copyright on that source? The original Atari has been bankrupted and merged and reverse-merged a number of times to the point where the current "Atari" is really nothing more than a company that bought the trademark 2nd or 3rd hand.
    Without a clear owner to file a copyright infringement case, this simple free distribution isn't likely to get anyone in trouble.

  • by Anonymous Coward on Friday July 03 2009, @08:22PM (#28576457)
    I can't speak for all SNES games, but as a (former) member of the Earthbound [wikipedia.org] hacking community, I can attest that Earthbound contains compiled code. I do not have it at my fingertips at the moment, but the ROM contains an ASCII (I think...) text string with the name of the compiler. Also, significant portions of the assembly code look like something no human would have ever written.
  • Re:score tables (Score:2, Interesting)

    by Sprite_tm (1094071) * on Saturday July 04 2009, @03:00AM (#28578325)

    It indeed is packed BCD. Some processors of that time have special instructions for that kind of notation, which makes calculating with them not much more difficult than normal binary. (Dunno if the 6502c has these kinds of opcodes, though; the Z80 for example does.) The advantage is that it makes blitting to screen really easy: instead of constantly dividing by 10, which is a processor-intensive task, you could just bitshift the number, which is much easier.

  • by PhysicalEd (744021) on Sunday July 05 2009, @03:04AM (#28584911)
    yes, this is true. I was the lead on the port of Robotron to the 7800 at GCC, and all we had to go with was the arcade machine. So first of all we had to become expert players, at all difficulty levels. At GCC we started videotaping gameplay with a camera over the shoulder so we could study movement and derive rules for the "AI", and even just to know how many critters of the various kinds appeared on the different levels. Needless to say, becoming an expert Robotron player payed off over the years...

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