floppy low level format question

From: Jules Richardson <julesrichardsonuk_at_yahoo.co.uk>
Date: Mon Jun 14 13:57:12 2004

On Mon, 2004-06-14 at 18:40, Tom Jennings wrote:
> >
> > > Question is, is this a standard? I mean, for any disk using MFM or FM
> > > recording are these bit patterns going to be the same?
>
> Standards schmandards, we have lots of standards!
>
> If you want to read any possible floppy format, then the only thing you
> can rely on is transitions to/from 0/1, and the DSP approach is about
> right.

That does seem to be the case from what others have said so far.

I should have actually made myself a bit clearer - in that I'm only
interested in backing up floppies and being able to restore them later.
I don't need to actually understand the contents on the machine which is
performing the backup.

Having said that, I'd rather not have each floppy take up several
megabytes due to overampling of the data stream - so I do still need to
make sense of bit transitions and record those.

"being able to restore them later" is perhaps a seperate project - I'd
be almost content just knowing that I had a copy of the raw data from a
floppy in the event of failure, even if currently I had no way of
restoring it.

Being able to do this from one platform, at least for any FM/MFM encoded
soft-sectored floppy (which for me is what 99% of my collection uses) is
pretty desirable. If I had room I'd have all my machines set up and laid
out - but as it stands nearly everything has to reside stored away,
which means it's a pain to do anything as soon as some new software
lands on the doorstep.

cheers

Jules
Received on Mon Jun 14 2004 - 13:57:12 BST