5 ms·

So how was the code trap implemented?

by mordechai9000 7y ago

deleted 7y ago
[deleted]
bagels 7y ago
Sounds like a coded message in the rom dump
- WarOnPrivacy 7y ago
  That's where but not how. "This trap consists of a particular data pattern. Only with the help of special code is it possible to read this pattern." This is the key part of the story & it's totally unexplained. The blogger "Tony" just dropped it in there with no vetting at all, as if the method was self evident. Such is news in the new millennia. The claim could just be bullcrap. Atari would have known that courts are tech-illiterate and the defendant might not have shown up for the hearings.
  - videotopia 7y ago
    Well to be fair, all there is to go on at this point is that document. The blog is pitched at a wide audience and is meant to be a "light" entertaining read, rather than something in depth and technical. But agreed, it would be interesting to know the exact process of "extracting" the coded message. The point of the article is that it was there (or to your point, it was claimed in court that it was there!), rather than how it got there. Bottom line - it did the trick.
    - daveFNbuck 7y ago
      Ed Logg is alive today according to his Wikipedia entry, so there's more to go on if someone wants to do write something more detailed about this incident.
umvi 7y ago
Sounded like steganography... Encoding Morse code into unused bits in the ROM
13of40 7y ago
A little bit of googling shows the ROM is available. Might be a good weekend project to bust out your disassembler and find out...
sehugg 7y ago
Yeah, I don’t get it. You could just compare the ROMs directly. I can XOR any arbitrary secret message with a long enough key.
- kbsletten 7y ago
  From the article, it wasn't a XOR, the "key" was that there was a bit sequence when interpreted as Morse code said something like "copyright ATARI". So, reasonably easy to show it wasn't just pulling the message out of thin air.
- pkaye 7y ago
  The ROMs wouldn't an exact match so you have to convince the layman jury that the differences are meaningful. The best way it to show something totally unexpected in the pirated code like your own copyright.
kabdib 7y ago
I wrote a few game cartridges for the Atari 400/800 computers when I was there in the early 80s. We were told to include a specific bit pattern, I think it was 5 or 8 bytes long, somewhere in our code. The idea was that the presence of a non-functional, unique bit pattern was going to be very difficult for a defendant to explain in court, since pirates mostly just copied ROMs and made minimal changes to obvious bitmaps and strings. Even if they found the mysterious bit pattern and were clever enough to (say) zero it out, they'd have to explain why most of a ROM was identical except for visible assets and that one set of bytes with no function ("What are these bytes for? Oh, you don't know? Let us show you...") We weren't told what the pattern meant. I played with it for a couple of hours once; I knew it wasn't executable 6502 code or simple logical bit operation (NOT, reverse bits, etc.) of anything obvious. Morse code makes sense now. Some coinop machines (Tempest, for sure) used character encodings so that the visible copyright messages were also executable code; changing the message, even slightly, would crash or have unpredictable behavior. In the case of Tempest, when the "final" ROMs were released to manufacturing, the dev team went on vacation while production ramped up. Some lawyer decided that the copyright message had to change, so they patched the ROM on the factory floor. Unfortunately this modification didn't lead to an immediate crash, but opened up a hole where the contents of the score line could do things like give you 100 extra lives (e.g., die with the low digits of your score being "50" and you'd be able to play for free for hours).
- i_am_nomad 7y ago
  Side note here, the Atari 800 was my first computer, and I absolutely loved every minute of it. Thanks for all your work and ingenuity, they gave me a good start on a career in technology. One question: why didn’t the Atari 800 ever take advantage of the double cartridge ports?
  - kabdib 7y ago
    My understanding was that the second cartridge slot was not a very well thought out thing. I think there was one cartridge made for it (some debugging tool?) That port cost a lot of money per unit; Atari's early efforts were not very well cost reduced. If they'd been more aggressive about cost reductions (and improving I/O speeds) they might have done much better in the market against Commodore. Instead we got more unclear hardware directions (the 1200XL's "Help" key was a prime example of the hardware group just not caring about or talking to the software folks), even more expensive machines, and a bunch of work being done by outside contractors instead of inside staff because it was easier to build empires that way. The 7200 game machine (developed by General Computer Corporation in Cambridge, IIRC) was a surprise to most of us, for instance, and not a good one.

So how was the code trap implemented?

deleted 7y ago

[deleted]

bagels 7y ago

Sounds like a coded message in the rom dump

WarOnPrivacy 7y ago
That's where but not how. "This trap consists of a particular data pattern. Only with the help of special code is it possible to read this pattern." This is the key part of the story & it's totally unexplained. The blogger "Tony" just dropped it in there with no vetting at all, as if the method was self evident. Such is news in the new millennia. The claim could just be bullcrap. Atari would have known that courts are tech-illiterate and the defendant might not have shown up for the hearings.
- videotopia 7y ago
  Well to be fair, all there is to go on at this point is that document. The blog is pitched at a wide audience and is meant to be a "light" entertaining read, rather than something in depth and technical. But agreed, it would be interesting to know the exact process of "extracting" the coded message. The point of the article is that it was there (or to your point, it was claimed in court that it was there!), rather than how it got there. Bottom line - it did the trick.
  - daveFNbuck 7y ago
    Ed Logg is alive today according to his Wikipedia entry, so there's more to go on if someone wants to do write something more detailed about this incident.

umvi 7y ago

Sounded like steganography... Encoding Morse code into unused bits in the ROM

13of40 7y ago

A little bit of googling shows the ROM is available. Might be a good weekend project to bust out your disassembler and find out...

sehugg 7y ago

Yeah, I don’t get it. You could just compare the ROMs directly. I can XOR any arbitrary secret message with a long enough key.

kbsletten 7y ago
From the article, it wasn't a XOR, the "key" was that there was a bit sequence when interpreted as Morse code said something like "copyright ATARI". So, reasonably easy to show it wasn't just pulling the message out of thin air.
pkaye 7y ago
The ROMs wouldn't an exact match so you have to convince the layman jury that the differences are meaningful. The best way it to show something totally unexpected in the pirated code like your own copyright.

kabdib 7y ago

I wrote a few game cartridges for the Atari 400/800 computers when I was there in the early 80s. We were told to include a specific bit pattern, I think it was 5 or 8 bytes long, somewhere in our code. The idea was that the presence of a non-functional, unique bit pattern was going to be very difficult for a defendant to explain in court, since pirates mostly just copied ROMs and made minimal changes to obvious bitmaps and strings. Even if they found the mysterious bit pattern and were clever enough to (say) zero it out, they'd have to explain why most of a ROM was identical except for visible assets and that one set of bytes with no function ("What are these bytes for? Oh, you don't know? Let us show you...") We weren't told what the pattern meant. I played with it for a couple of hours once; I knew it wasn't executable 6502 code or simple logical bit operation (NOT, reverse bits, etc.) of anything obvious. Morse code makes sense now. Some coinop machines (Tempest, for sure) used character encodings so that the visible copyright messages were also executable code; changing the message, even slightly, would crash or have unpredictable behavior. In the case of Tempest, when the "final" ROMs were released to manufacturing, the dev team went on vacation while production ramped up. Some lawyer decided that the copyright message had to change, so they patched the ROM on the factory floor. Unfortunately this modification didn't lead to an immediate crash, but opened up a hole where the contents of the score line could do things like give you 100 extra lives (e.g., die with the low digits of your score being "50" and you'd be able to play for free for hours).

i_am_nomad 7y ago
Side note here, the Atari 800 was my first computer, and I absolutely loved every minute of it. Thanks for all your work and ingenuity, they gave me a good start on a career in technology. One question: why didn’t the Atari 800 ever take advantage of the double cartridge ports?
- kabdib 7y ago
  My understanding was that the second cartridge slot was not a very well thought out thing. I think there was one cartridge made for it (some debugging tool?) That port cost a lot of money per unit; Atari's early efforts were not very well cost reduced. If they'd been more aggressive about cost reductions (and improving I/O speeds) they might have done much better in the market against Commodore. Instead we got more unclear hardware directions (the 1200XL's "Help" key was a prime example of the hardware group just not caring about or talking to the software folks), even more expensive machines, and a bunch of work being done by outside contractors instead of inside staff because it was easier to build empires that way. The 7200 game machine (developed by General Computer Corporation in Cambridge, IIRC) was a surprise to most of us, for instance, and not a good one.