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Atari 8-bit Software Preservation Initiative


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42 minutes ago, Great Hierophant said:

A friend of mine noted that both Choplifter! (1982)(Broderbund Software)(US)[a][!].atx and Choplifter! (1982)(Broderbund Software)(US)[a2][!].atx in the a8preservation archive replace the copy-protection check at $067D with a JMP past it.  In other words, these are cracked disks.

These dumps are from original disks and they are not cracked at all.

They still have their duplicate sector protection. They only skip a bad sector check for unknown reasons.

 

Look here and open the entries of the [a]- and [a2]-release. You will find documentation on the protections.

... and I found an error in it. The EOR for [a2] certainly does not use the bad sector's status code but an #$90. :)

 

Information about the dumps can be found in our database:

[a]-release with a photo of the disk

[a2]-release unfortunately without further information

Edited by DjayBee
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On 10/14/2022 at 11:55 AM, Great Hierophant said:

A friend of mine noted that both Choplifter! (1982)(Broderbund Software)(US)[a][!].atx and Choplifter! (1982)(Broderbund Software)(US)[a2][!].atx in the a8preservation archive replace the copy-protection check at $067D with a JMP past it.  In other words, these are cracked disks.  Should they have the [!] label attached to them, which I understand to mean a pristine dump of original media?

 

Just because the protection, or part of it, seems to be bypassed, doesn't mean it is a crack. As @DjayBee explained, the disk is still copy protected and the main protection is still checked. I've seen cases even worse than this one, where the whole copy protection check was removed.

 

The images come from original disks. It is true that doesn't by itself gives a 100% certainty. I've seen cracks recorded on original disks. So we use different methods to confirm the authenticity of the data. The most important is simply compare and verify multiple copies of the same release. In this particular case we have many, so there is no (much) doubt about the issue.

 

I'm not sure why the partial protection check was removed and I'm too lazy to investigate it. I seem to remember that some earlier Broderbund releases had some compatibility problems with certain disk drives. So it is conceivable they implemented some modifications to avoid these issues. Or may be they wanted to avoid the ugly noise, and delay, that you get when attempting to read such a bad sector. After all this wasn't really needed to verify the copy protection. But don't know, this is really not much more than just a speculation.

 

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2 hours ago, ijor said:

 

Or may be they wanted to avoid the ugly noise, and delay, that you get when attempting to read such a bad sector. After all this wasn't really needed to verify the copy protection. But don't know, this is really not much more than just a speculation.

 

But who doesn't love the sound of a bad sector check on an 810 drive?  First thing I did with AMAC was back it up and disable the bad sector check, so I wouldn't have to listen to it every time I switched between editor and assembler.

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I have noticed several odd things about another Broderbund game, "Apple Panic". There are three disk images in the Preservation Initiative:

  1. Apple Panic (1982)(Broderbund Software)(US)[disk] (CRC e76f1e59): As mentioned in the database, this version matches what Atarimania calls the "prototype" version (http://www.atarimania.com/game-atari-400-800-xl-xe-apple-panic_29071.html), except that "Olaf Lubeck" is not misspelled. What surprises me and what is not mentioned in the database description however is the fact that you cannot actually kill enemies that you have trapped. The latter behavior makes this game effectively unplayable, which is why I am surprised to see it on an original disk. Unless there is a way to kill trapped enemies after all that I am not seeing, and that would be radically different from the later version. I would call this version "rev 1".
  2. Apple Panic (1982)(Broderbund Software)(US)[a2][disk] (CRC 40a6e866): This version behaves similarly to what Atarimania calls the "released" version. It performs a similar "bad sector" check as Choplifter! and uses the $90 status as a XOR value for something (routine starting at PC $0606). Annoyingly, it messes with the keyboard interrupt vector at $0208 and never restores it, causing the game to crash whenever you hit any key on the keyboard (except for START), at least in Atari800 and Altirra. Again, I am surprised that a version with such a severe bug would be released. I would call this version "rev 2".
  3. Apple Panic (1982)(Broderbund Software)(US)[a][disk] (CRC 2ac89462): This is similar to "rev 2", *still* corrupting the keyboard interrupt vector, but removing the "bad sector" check similarly to the later version of Choplifter!, hard-coding the expected $90 return value instead, and re-using some of the bytes that had beeen used for that now to *disable* the keyboard interrupt via $D20E, so that hitting any key in-game no longer crashes the game despite the corrupted keyboard interrupt vector. I would call this version "rev 3". This is the only version that I would consider "acceptable for play".

Can somebody confirm my findings? Am I wrong on any aspect?

Edited by NewRisingSun
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"Just because the protection, or part of it, seems to be bypassed, doesn't mean it is a crack."

 

Yeah, it depends a bit on the definition of "crack", and whether the term may be used to denote the publisher themselves removing any part of a protection check by directly modifying the binary data with NOPs, as opposed to removing the instructions and recompiling/reassembling from source code, as one might expect. I admit that the latter situation is not what most people have in mind when they read "crack".

Edited by NewRisingSun
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2 hours ago, NewRisingSun said:

Can somebody confirm my findings? Am I wrong on any aspect?

I did a binary compare between the prototype from Atarimania and the non-[a] release. It confirmed your assumption. There are only a few bytes different.

A binary compare between both [a]-versions led me to the conclusion that disabling the keyboard interrupt is the only difference between them.

 

2 hours ago, NewRisingSun said:

Yeah, it depends a bit on the definition of "crack",

We have several re-releases of Scott Adams and Sierra adventures from Green Valley Publishing as original disks which really are cracks. There is no more copy protection in place due to NOPing oder replacing BMIs/BPLs with their respective opposite.

 

Regarding Choplifter and Apple Panic:

I never understood why Broderbund did that.

Ijor's assumption that the disk drives' noises, particularly the 810s', might have been the reason. After all, duplicate sectors are the much more sophisticated copy  protection than missing sectors; and these are still in place.

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Thanks for your detailed analysis, @NewRisingSun.

7 hours ago, NewRisingSun said:

The latter behavior makes this game effectively unplayable, which is why I am surprised to see it on an original disk. Unless there is a way to kill trapped enemies after all that I am not seeing, and that would be radically different from the later version.

I know this is a full retail release because it was a disk my father bought from a local computer store in 1982. I'm not sure what problem you are seeing, but I just tested and if you hit a trapped apple repeatedly over the head with your shovel, it will fall through the hole and disappear. You need to let the shovel bashing happen "automatically" via a single button press.

 

MACE Newsletter v2n4 (April 1982) mentions that the version they tested occasionally doesn't play sound when digging. I saw this same phenomenon with our e76f1e59 ATX so that supports your theory that it is likely the first release.

 

Based on your analysis, I have swapped [a] and [a2] in our database and noted how they differ [a keyboard crash bug] and [a2 no bad sector check].

Edited by Farb
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7 hours ago, NewRisingSun said:

"Just because the protection, or part of it, seems to be bypassed, doesn't mean it is a crack."

 

Yeah, it depends a bit on the definition of "crack", and whether the term may be used to denote the publisher themselves removing any part of a protection check by directly modifying the binary data with NOPs, as opposed to removing the instructions and recompiling/reassembling from source code, as one might expect. I admit that the latter situation is not what most people have in mind when they read "crack".

 

Please don't start a semantic debate. I was answering to @Great Hierophant that claimed that the disks are "not original media", and they do are original media. If you still want to call them a crack, well, if you want ...

 

I could argue that even if the "cracker" reassembles the (disassembled) code, instead of patching the binary data with a NOP, I would still call it a crack. But again, it would be semantics.

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No interest in starting a debate, just inquiring whether there is any official terminology in this scene.

 

I am still intrigued by the fact that an OS version difference could have such a subtle effect on gameplay, and investigated further. In Apple Panic rev1, in the moment at which the trapped enemy is supposed to fall through the floor after hitting it several times with the shovel, it executes this code at PC $4B8F:

LDA $44C5,X
CMP $FFF6

BCC $4B96

The byte at $FFF6 is $FF in OS-B, and $01 in BB01 rev2. Changing the "CMP $FFF6" to "CMP #$FF, NOP" makes the game work properly on all OS versions. (So the filename should have an "[OS-B]" tag.)


I cannot think of a reason why a game would use a hard-coded BIOS location as a source for a simple $FF value. Did they expect software pirates to be dissuaded by that in some way? Does this prevent the use of any cheating device that would have to have existed in 1982?

Edited by NewRisingSun
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I can't remember what year the Omnimon came out but I don't see any effect on it being resident that would affect it. I can't remember any games that were properly protected from it. I was told by the authors that Sidewinder was protected against the Omnimon, but I think Mr Sosta was just hamming it up when he said it to me. I seem to remember Savage Pond filling memory and over writing itself, mind you it was just a simple bad sector check. I think it may have looked around the $C000 area, but that is from my shaky memory.

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On 10/20/2022 at 5:17 AM, NewRisingSun said:

The byte at $FFF6 is $FF in OS-B, and $01 in BB01 rev2. Changing the "CMP $FFF6" to "CMP #$FF, NOP" makes the game work properly on all OS versions. (So the filename should have an "[OS-B]" tag.)


I cannot think of a reason why a game would use a hard-coded BIOS location as a source for a simple $FF value. Did they expect software pirates to be dissuaded by that in some way? Does this prevent the use of any cheating device that would have to have existed in 1982?

 

I don't know about this particular case. But there are plenty of similar issues, and in most cases the reason is very simple. It's a "harmless" bug, it's not intentional, might be even a typo. And because the bug was harmless, at least at the system it was developed and tested, it wasn't exposed and it wasn't fixed.

 

Again, might be different in this particular case. You can never know for sure. But that's the typical case.

 

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6 minutes ago, tschak909 said:

Wow, really?

Kinda surprising, considering its popularity. Bounty Bob never got a disk release either, though (although there were a couple of cassette versions released in Europe).

 

Edited by MrFish
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  • 2 months later...

I just purchased the APX version of Galahad and the Holy Grail off Ebay and I noticed that the title screen is a little different from the one that is in the archive.  The copyright line on my copy starts with the words "Special Edition".  I don't see this on the archive copy.  The disk shows this is version 1.2.

 

edit: I've attached an ATX copy that I made using my 810 Archiver.

Galahad and the Holy Grail V12.atx

 

Galahad_title.thumb.jpeg.90283ba309cbff659306bf3d1f93e12f.jpeg

Galahad_disk.thumb.jpeg.7f67c26cd12737d776cc784366e58648.jpeg

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6 hours ago, www.atarimania.com said:

It would be interesting to make a side-by-side comparison of this V1.2 and the Antic Software release (knowing that the early APX edition from 1982 is said to be quite buggy).

I did a quick comparison and the code appears to be a different assembly.  It would need to be disassembled to identify the differences.  I did find some text identifying the version of each disk.

 

From the archived version - Galahad and the Holy Grail (1982)(APX)(US)[!].atr
APX-20132›GALAHAD AND THE HOLY GRAIL›DOUGLAS CROCKFORD›07/16/82›0›

 

And from my copy.

APX-20132›GALAHAD AND THE HOLY GRAIL 1.2›DOUGLAS CROCKFORD›03/21/83›0›

 

Mine has a newer revision date.

 

 

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4 hours ago, tep392 said:

I did a quick comparison and the code appears to be a different assembly.

Do you mean between both APX revisions? Or is that between the "Special Edition" and the Antic Software rerelease? 

 

I looked in my "collection" and noticed I also had a cracked copy of the "Special Edition". The revision date matches yours so at least chances are there's just a single "V1.2". This also begs the question whether a "V1.1" exists.

 

For more headaches, though, here are two more "versions" with no DISKNAME.DAT file so where these come from is anybody's guess:

Galahad and the Holy Grail + Unknown #1.atr

Galahad and the Holy Grail + Unknown #2.atr

 

 

 

 

 

 

 

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Well, I can ask Douglas?

 

Please find the solution of Galahad and the Holy Grail below.

 

1st turn in daylight, 2nd at night in the dark, same rooms, same enemys.

The beginning of the 3rd turn ist the "end" of the game. But in real you can start the 2nd over and over again, because, according to Douglas, a real knight is immortal...

You will never ever see a screen "End"... ;-)

Galahad-solution.jpg

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18 minutes ago, luckybuck said:

Well, I can ask Douglas?

 

Please find the solution of Galahad and the Holy Grail below.

 

1st turn in daylight, 2nd at night in the dark, same rooms, same enemys.

The beginning of the 3rd turn ist the "end" of the game. But in real you can start the 2nd over and over again, because, according to Douglas, a real knight is immortal...

You will never ever see a screen "End"... ;-)

Galahad-solution.jpg

Seemingly Immortal as they protect the Holy Grail and drink of it. So the lights may go out eventually one way or another but not due to health reasons.

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16 hours ago, www.atarimania.com said:

Do you mean between both APX revisions? Or is that between the "Special Edition" and the Antic Software rerelease? 

 

I looked in my "collection" and noticed I also had a cracked copy of the "Special Edition". The revision date matches yours so at least chances are there's just a single "V1.2". This also begs the question whether a "V1.1" exists.

 

For more headaches, though, here are two more "versions" with no DISKNAME.DAT file so where these come from is anybody's guess:

Galahad and the Holy Grail + Unknown #1.atr 90.02 kB · 4 downloads

Galahad and the Holy Grail + Unknown #2.atr 90.02 kB · 4 downloads

 

 

 

 

 

 

 

I was comparing mine to the archived APX version.  The two unknown versions you posted look to be based off the archived APX version. 

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