Floppies was Re: E-Mail-Adress

[Chuck Guzis]

On 21 Feb 2008 at 22:30, Dave Dunfield wrote:

> I do have a preliminary utility I wrote to extract CP/M files from ImageDisk
> CP/M images - Worked very well for me in extracting some CDOS files, however
> I didn't get much interest in it so I never bothered to expand it into a
> general purpose utility - it is configurable however - I can make it available
> if you want to play with it. You will need to figure out the right parameters
> for Bigboard disks (the tables for Chucks 22disk might be helpful).

I do have a version of ctod that works from "straight" image files of 
floppies (i.e., the sectors appear in consecutive order (no physical 
interleave) and in side-to-side ordering.  It works for my purposes 
(mostly reading images formed from Catweasel maps), but might not 
with all formats.

The world of CP/M diskettes is far more complex than simple 22Disk 
can manage.  There's a special version that I sell where we have to 
program the sector mapping algorithm--there are formats that employ 
logical cylinder- and side-skewing as well as starting at a central 
cylinder and working outwards using alternate traks on either side of 
the directory.  One or two formats use differently-sized sectors on 
each track.   This isn't even counting the differing recording 
methods, such as GCR or zoned sector packing.

The imagination of CP/M CBIOS authors never ceases to surprise me.

Cheers,
Chuck