Floppy Low Level Format

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~
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Floppy Low Level Format

Post by ~ »

Does anybody knows if it's possible or suitable to format a 1.4Mb floppy as a 2.8Mb, and whether current floppy drives support such format?

Or at least somebody knows how to format a 1.4Mb floppy as a 1.6Mb one? I have seen that Linux ends up with such big disks when one is installing it and one allows it to make a boot diskette.
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Post by mystran »

I have yet to see in real life a drive that supported 2.88MB.

As for writing 1.6MB on 1.44MB disk, the trick (if I've understood correctly) is simply to cheat by having shorter than standard gaps between sectors.
The real problem with goto is not with the control transfer, but with environments. Properly tail-recursive closures get both right.
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Post by Brynet-Inc »

Attempting to increase the capacity of a disk is normally not recommended, for data reliability and performance.. (If this even exists on a floppy..)

But also, quite a few systems are locked into preset formats. Thus witting 1.6mb on a disk might be theoretically possible, reading it on another system might take some work.

One example of a cheat is Microsoft's DMF: http://en.wikipedia.org/wiki/Distribution_Media_Format
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Post by mystran »

Well Linux supports directly at least:

Code: Select all

/dev/fd0u1040@
/dev/fd0u1120@
/dev/fd0u1440@
/dev/fd0u1600@
/dev/fd0u1680@
/dev/fd0u1722@
/dev/fd0u1743@
/dev/fd0u1760@
/dev/fd0u1840@
/dev/fd0u1920@
/dev/fd0u360@
/dev/fd0u720@
/dev/fd0u800@
/dev/fd0u820@
/dev/fd0u830@
/dev/fd0 is supposed to autodetect as far as I know. Having tested those years ago, anything larger than 1680 works pretty unreliably though. I know of people that have had success using 1840 disks.
The real problem with goto is not with the control transfer, but with environments. Properly tail-recursive closures get both right.
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Post by inflater »

When I was 7-8 years old, I had a IBM with 486 inside. It had a 2,88 MB floppy drive though and it formatted, I think, standard 1,44 MB HD floppies to 2,88 MB without any problems. (I think).

After that, I tried to experiment with Microsmeg's new scam, DriveSpace3 and made a ~5 MB "sized" floppy readable only with Windows 95 with Drive space 3 installed. The floppy wasn't reliable, though.

I succeeded with 1,72 MB format in Windows 95 and 1,68 MB format (aliases: DMF format by M$) in Windows XP by using WinImage. :) And no stinkin' compression things! :D

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Post by AJ »

USB flash drive, anyone?
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Post by mystran »

AJ wrote:USB flash drive, anyone?
Well yes, I do have one (edit: two actually, one can play mp3's as well), and yes, I do use it instead of floppies, but then again my kernel can't yet support USB..

But yeah, in the long run it's waste of time to try to figure out how to get small floppies a bit bigger, when you could just figure out how to deal with an USB stick.
The real problem with goto is not with the control transfer, but with environments. Properly tail-recursive closures get both right.
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