Early 5.25 PC disk, can't create working MFM image

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hydr0x
Posts: 104
Joined: Wed Dec 29, 2010 4:01 pm

Re: Early 5.25 PC disk, can't create working MFM image

Post by hydr0x »

NRS wrote:This is similar to Gremlins. The program image is in 1024 byte sectors (and that's the copy protection), while the tracks not containing any data are unformatted. These games don't check whether the tracks actually are unformatted (unlike Zaxxon, for example), so it may just have made the copying process faster with whatever equipment they were using.
I'm not sure I follow. Your hunch is right, the N-track uses 1024-byte sectors and decodes properly if I create a 1024-byte sector image (the others don't). So far, so good. I assume I need to use PCE to work with this image. But what about the fact that half the side 1 is blank? Are you suggesting they left it unformatted because they didn't need the space anyways and copying was faster this way?

NRS
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Re: Early 5.25 PC disk, can't create working MFM image

Post by NRS »

Yep.

hydr0x
Posts: 104
Joined: Wed Dec 29, 2010 4:01 pm

Re: Early 5.25 PC disk, can't create working MFM image

Post by hydr0x »

Interesting, thanks.

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IFW
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Joined: Mon Nov 08, 2010 2:42 pm

Re: Early 5.25 PC disk, can't create working MFM image

Post by IFW »

That was a fairly common thing to do on Atari ST and early Amiga releases - I have not seen it on PC yet though.

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mr.vince
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Joined: Tue Oct 05, 2010 5:48 pm

Re: Early 5.25 PC disk, can't create working MFM image

Post by mr.vince »

Unless that disk was meant to be used as a "working disk" makes sense if "install only" or "boot only" was the plan.

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