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Thread: Sierra original 720K floppies (KQ1, LSL1)

  1. #11
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    Quote Originally Posted by Stone View Post
    Is it possible that the original 720K disk is no longer original? By that I mean could the files from the two 360K disks have been copied at some point to that 720K disk for whatever reason? If that's the case the copy protection could fail since the game is going to look for a second disk.

    Alternatively, have you tried ejecting the disk when it asks for the game disk and then re-inserting it and then pressing enter?
    No, the floppy has been verified and its un touched. I (same for KQ2) 've tried ejecting to see if it errors out but the green floppy light stays on and my IBM is un responsive. I need to power off and on to continue.

  2. #12
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    Quote Originally Posted by jafir View Post
    Didn’t some games have copy protection where it would move (or maybe edit) a file from the floppy to the hdd, and you had to uninstall the game (so it would copy that file back to the floppy) to be able to install the game again?

    yes, but with Sierra we know exactly what the copy protection is, even how it's doing it, what sectors are used etc. But what I don't understand is why the IBM 5170 8mhz fails. Its gotta be timing. I guess trixters is the one to ask as he is the coding guru.

  3. #13

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    So, to sum up:

    1) The original 720K disk works fine but not on the 5170.

    2) The cracked 720K disk works fine on the 5170.

    The conclusion is that the 5170 can't handle the copy protection.

    Out of curiosity, can you try both the cracked and the original 720K disks on an XT or maybe a slow 286 clone?
    PM me if you're looking for 3½" or 5¼" floppy disks. EMail “ ” For everything else, Take Another Step

  4. #14
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    Quote Originally Posted by Stone View Post
    So, to sum up:

    1) The original 720K disk works fine but not on the 5170.

    2) The cracked 720K disk works fine on the 5170.

    The conclusion is that the 5170 can't handle the copy protection.

    Out of curiosity, can you try both the cracked and the original 720K disks on an XT or maybe a slow 286 clone?

    This is correct. Unfortunately my IBM 5160 does have a external 720k floppy drive BUT I have the problem as many people do with these drives. The drive reads, writes formats, copy BUT only a disk formatted on that drive. Any other floppy I insert is not readable. So in other works I cant test it. Funny thing if this original floppy disk works on my PII machine. So I gather its something with the 5170's hardware that affects the CP.

  5. #15

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    Quote Originally Posted by robbo007 View Post
    TUnfortunately my IBM 5160 does have a external 720k floppy drive BUT I have the problem as many people do with these drives. The drive reads, writes formats, copy BUT only a disk formatted on that drive. Any other floppy I insert is not readable. So in other works I cant test it.
    FWIW, I'm using a 1.44MB HD floppy on my 5160 as described here.

    Alternatively, you could plug a standard 720K or 1.44M drive directly into the 5160's existing controller. Both would work however the 1.44M would only function with 720K disks.
    PM me if you're looking for 3½" or 5¼" floppy disks. EMail “ ” For everything else, Take Another Step

  6. #16
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    Quote Originally Posted by robbo007 View Post
    yes, but with Sierra we know exactly what the copy protection is, even how it's doing it, what sectors are used etc. But what I don't understand is why the IBM 5170 8mhz fails. Its gotta be timing. I guess trixters is the one to ask as he is the coding guru.
    I don't know about Sierra's copy protection, but some could take different code paths if they detect different kinds of machines.

    What year were these disks produced? 3.5" 720k was considered kind of non-standard until the release of the IBM PS/2. If they were released before that, it could be your disks were intended for some specific PC clone.

    What drive is in the system? There is even the slight possibility the compatibility is with the drive itself. For one example, if the software modifies the head step rate, it could crap itself when used in very early 720k drives. My money would still be on some glitch detecting timing, though.

    If it were me, I might also try testing with a different BIOS, such as a more feature rich one from a later 286-clone. BIOS issues were a common source of compatiblity problems, although one would expect a genuine IBM to work.

    It would be interesting to narrow down the issue.

  7. #17

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    Quote Originally Posted by SomeGuy View Post
    I don't know about Sierra's copy protection, but some could take different code paths if they detect different kinds of machines.
    Sierra used an well known off the shelf copy protection system and disk duplicator. (Softguard SuperLok). There are no hidden code paths in that.

  8. #18
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    I've just tested the 360k originals on my IBM 5170 and the same results. Complete computer lockup. Need to hard power off and on to get it going. These same disks run flawlessly on my IBM 5160, well the 360K disk that is, as in another post my external 720k drive is acting strangely.

  9. #19

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    Quote Originally Posted by Trixter View Post
    I seem to recall stories of the copy protection failing on certain 5170s.
    Quote Originally Posted by Trixter View Post
    I don't recall the specifics of the stories, sorry. It might be a factor if your 5170 is 6MHz or 8MHz.
    Quote Originally Posted by robbo007 View Post
    So I gather its something with the 5170's hardware that affects the CP.
    Quote Originally Posted by robbo007 View Post
    I've just tested the 360k originals on my IBM 5170 and the same results. Complete computer lockup. Need to hard power off and on to get it going. These same disks run flawlessly on my IBM 5160, well the 360K disk that is, as in another post my external 720k drive is acting strangely.
    It sure looks like it's a specific hardware compatibility issue. All your disks are good. Only one machine chokes on all of them. You're not very likely to determine exactly what that issue is -- unless you're willing to dedicate the rest of your natural life to it and even then it's iffy.
    PM me if you're looking for 3½" or 5¼" floppy disks. EMail “ ” For everything else, Take Another Step

  10. #20
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    haha. We need good old Peter Norton on the case Well "one machine" happens to be an IBM 5170 8mhz. Guess they didn't sell to many of these. haha. Maybe something like SOFTiCE will help. But I think that only works on 386+ CPU's. Would be good to pause the program and debug it. In the end there is so much information I'm not sure how to document or archive all my findings. Google is getting too bloated. We need one area for Retro computing. Something like MobyGames but with technical sections where people could contribute copy protection schemes, strange errors on real hardware etc etc.

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