Stumped on a Cartridge Repair

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t0nyt
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Stumped on a Cartridge Repair

Post by t0nyt »

Still on the trail of repairing some original Cartridges and am currently stuck on Talent's "West" adventure

I've recovered the Cartridge and the MDV image works fine in q-emulator

It also works fine when I run from vDrive on a BBQL

BUT if I re-image it back to a cartridge it fails the protection check (and wipes the cartridge!)
Have used various tools, which have always worked before, but I can't get a real cartridge to work for West

I even re-restored from the cartridge I created (before it got wiped!) and again it works in q-emulator, but when I re-image that back to a cartridge it fails again

I've checked the random mdv number on all of them with a hex editor and it's always the correct same value on all copies (which as I understand it is what West tests for) so am totally stumped now

I was wondering if anyone has any thoughts or suggestions to try please?

Many thanks


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Re: Stumped on a Cartridge Repair

Post by tofro »

t0nyt wrote: Mon Feb 03, 2025 6:35 pm Still on the trail of repairing some original Cartridges and am currently stuck on Talent's "West" adventure

I've recovered the Cartridge and the MDV image works fine in q-emulator

It also works fine when I run from vDrive on a BBQL

BUT if I re-image it back to a cartridge it fails the protection check (and wipes the cartridge!)
Have used various tools, which have always worked before, but I can't get a real cartridge to work for West

I even re-restored from the cartridge I created (before it got wiped!) and again it works in q-emulator, but when I re-image that back to a cartridge it fails again

I've checked the random mdv number on all of them with a hex editor and it's always the correct same value on all copies (which as I understand it is what West tests for) so am totally stumped now

I was wondering if anyone has any thoughts or suggestions to try please?

Many thanks
Some of the copy protection "back then" was based on the fact that microdrives can contain duplicate sectors (same sector number, header and data) without any problems. Copier programs normally only copy one of them. The check code simply checks if it can repeatedly read the very same sector in under 7 seconds.


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t0nyt
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Re: Stumped on a Cartridge Repair

Post by t0nyt »

Thanks Tofro, that’s interesting information I hadn’t come across before and will be useful to know

With West I’ve just changed every occurrence of the random number in an mdv image and that version now fails protection check in q-emulator (though it doesn’t erase the image for some reason). Which seems to show it uses the random number check

But if it also does the check you detail, then that could explain why it works on q-emulator even when set at original speed as mdvs still run fast. Though vdrive is a lot slower but maybe just fast enough I guess

Many thanks


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t0nyt
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Re: Stumped on a Cartridge Repair

Post by t0nyt »

I guess the best thing I can do at this point is to run thru the mdv image, as it works with q-emulator, with a hex editor and check if it contains any duplicate sector numbers


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XorA
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Re: Stumped on a Cartridge Repair

Post by XorA »

So I am similarly stuck with Zkul and West on sqlay3, I always trip the copy protection, but the same image works on Q-Emulator.

So I am looking with eagerness that someone can explain the fine details of their copy protection!


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M68008
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Re: Stumped on a Cartridge Repair

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XorA wrote: Mon Feb 03, 2025 9:59 pm So I am similarly stuck with Zkul and West on sqlay3, I always trip the copy protection, but the same image works on Q-Emulator.

So I am looking with eagerness that someone can explain the fine details of their copy protection!
Weird, as far as I remember the original versions only used the sector header check.


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t0nyt
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Re: Stumped on a Cartridge Repair

Post by t0nyt »

M68008 wrote: Tue Feb 04, 2025 8:10 am
XorA wrote: Mon Feb 03, 2025 9:59 pm So I am similarly stuck with Zkul and West on sqlay3, I always trip the copy protection, but the same image works on Q-Emulator.

So I am looking with eagerness that someone can explain the fine details of their copy protection!
Weird, as far as I remember the original versions only used the sector header check.
I've just double checked my zKul mdv (from which I CAN re-create an original protected mdv) and it doesn't seem to use the random number as I changed it in all sectors and it still works

Maybe there were different protections used over time or something


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t0nyt
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Re: Stumped on a Cartridge Repair

Post by t0nyt »

Just realised I have a 2nd protected zKul image and that DOES use the random number protection, will try creating a cartridge from that one to see if it has the same issues as West


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XorA
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Re: Stumped on a Cartridge Repair

Post by XorA »

M68008 wrote: Tue Feb 04, 2025 8:10 am
XorA wrote: Mon Feb 03, 2025 9:59 pm So I am similarly stuck with Zkul and West on sqlay3, I always trip the copy protection, but the same image works on Q-Emulator.

So I am looking with eagerness that someone can explain the fine details of their copy protection!
Weird, as far as I remember the original versions only used the sector header check.
That's useful to know from an expert, so its likely then I am missing or incorrectly emulating something!


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t0nyt
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Re: Stumped on a Cartridge Repair

Post by t0nyt »

Have just tried creating a cart from the zkul image that uses header checks and it fails the protection check the same as West

So there must be something else going on here, especially as when I image it back from the new cart to mdv image it works fine in q-emulator

If it's as tofro describes it would mean having to work out what sector(s) it's checking on, no idea how to do that though yet


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