New subject: Universal Floppy reader, was : Re: Extracting CDOS and CP/M) files

12 Oct 2007

---------Original Message:
Date: Fri, 12 Oct 2007 09:09:22 -0700 (PDT)
From: Fred Cisin <cisin at xenosoft.com>
Subject: RE: Extracting CDOS and CP/M) files

...
  >Now that 22Disk and the rest of the tools have
been exonerated, we can
 >concentrate on ways to read the hard to read sectors - a ubiquitous
 >problem with Cromemco disks. 
On Fri, 12 Oct 2007, M H Stein wrote:
...
  Admittedly a problem when trying to read their disks
with today's crippled
 controllers, but their use of a common SD Track 0 meant that without any
 . . .
 It all just looks different from today's PC-centric perspective. 
No complaint about the idea of minimal first sector.
The specific problem that I was referring to is the incompatability with
trying to read Cromemco diskettes using an NEC 765 type controller, which
needs a larger index gap, resulting problems reading the first sector
of each track.

------------Reply:
Tell me about it; went through 7 mobo/fdcs while trying to help Dave D;
although some could write OK (which was all I really needed to recreate
his images), I never did find one that could *read* using IMD or Uniform.
Slowed down the drive, which sometimes helps, but still no good reads. 
That's why I keep at least one Cromemco system up & running; much 
easier to go the other way and copy to MSDOS disks on the Cromemco 
(or transfer files the old-fashioned RS-232 way).

Nevertheless, just wanted to point out that their format wasn't quite such
a dumb/bad thing as it seems from a PC POV; just too bad IBM picked 
the 765 instead of the 1793.

BTW, that disk ID in track 0 is not *required*; if it's not found, the controller
defaults to (stays in) SD/SS mode (although that doesn't mean that CDOS
will be able to read your particular flavour of CP/M disk unless it's the
IBM 8" "standard").

mike