[sebhc] fstools and other things

Eric J. Rothfus eric at rothfus.com
Wed Jun 2 17:18:43 CDT 2004

> So how do you get the volume number from a cpm image now?

The H17 image format had a volume number in the header.  All
CP/M disks do have a volume number on them as you point out.
However, the "diskdump" utility is pretty stupid about finding
the RIGHT volume number for a CP/M disk, trying to look into the
label sector for it...yup, the program crashes.

> But not for the volume number.  To really do it right, that , along
> with the sector address, would need to be carried separately for
> every sector.  And you'd still have to define these as part of a
> sector prefix, which exists separate from the data, with a "tunnel"
> area in between.

Never heard it called a "tunnel" before :-).  But, yup, that would be
the most "expressive" thing to do.  Granted, it is a judgement call,
but I didn't think that expressivity was necessary for a Heathkit
hard-sector controller image.  I asked before, and no one indicated
any special disks that would require it.

But I feel (again, judgement here) that the volume number is a bit
different story.  As far as I know, there's only one volume number for
an HDOS floppy as well as a CP/M floppy.  God knows why the
volume number is in the header of every sector.  But to accurately
represent a disk you have to have SOME volume number, and the number
can't be discerned or guessed easily (except for HDOS disks).  The
track and sector numbers can be fairly easily "guessed" or at least
"defined" as "the order in which they appear in the file."

> It'd be interesting to see if a cat-weasel would properly identify and 
> recreate sector headers and tunnels on an hdos disk.  :-)

I hear that it CAN'T handle hard-sectored disks.  However, the 
soft-sectored HDOS disks could probably be imaged right for both
the gaps and data.

Note that I should probably post the SVD PIC firmware sooner than later,
Steven would probably be able to parse it and offer some help
quickly!  Currently I'm working on the "write" capability.  Not too
hard, but takes time.


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