MDOS (Motorola EXORciser) disk format ?

From: James M. Walker <chejmw_at_acsu.buffalo.edu>
Date: Mon Nov 3 15:06:49 2003

Hi,
Jim here with an on topic question. Since the mention of CP/M, et al, I have
been
looking for the CP/M-86 original version 1.0 on the 8 inch single density
floppy. I
have the manuals (reprints/copies). I also have CP/M-86 for the IBM-PC, on
5.25 and 3.5 inch media, However I have yet to find anyone with the 8 inch
disk
that is the bootable version. This ran on the Intel 86-12 CPU board and had
drivers
that could be modified for various devices. I have an IDE driver software
fix that
will let me use IDE drives with my SBC-86/12 system. Any help out there?

Thanks
Jim
WB2FCN

----- Original Message -----
From: "Tom Jennings" <tomj_at_wps.com>
To: "General Discussion: On-Topic Posts Only" <cctech_at_classiccmp.org>
Sent: Monday, November 03, 2003 3:13 PM
Subject: Re: MDOS (Motorola EXORciser) disk format ?


> On Sun, 2003-11-02 at 14:54, Fred Cisin wrote:
> > > A friend of mine has a pile (55) 8" floppies which were created
> > > on a Motorola EXORciser MDOS system. Does anyone know if the data
> > > on these disks can be recovered on a CPM system or similar, or will
> > > he need to find an EXORciser?
>
> CP/M, since it's so close to the iron anyways, is probably a good way to
> do a sector dump of the disk. Copy it to a modern machine and
> post-process the data.
>
> Getting the sector data off is the task. If it's hard-sectored, you're
> probably screwed. (Turn the diskette inside it's sleeve; there should
> only be one (a pair?) of index holes. If you see 12 or so holes it's
> hard-sectored. Not many 8" diskettes were hard sectored.)
>
> There were two flavors of floppy controller chip in the 70's and 80's,
> th Western Digital chips and the NEC 765. I always preferred the WD
> chips (1791? 1793? I forget!) They were the best for diskette hacking.
> They would read any damn old FM or MFM signal, and you could dump to
> memory and do the bit extraction in software. Very cool. The NEC765,
> though nominally easier to do certain things, was a lot less flexible
> and far more fussy about format.
>
> (I used to run my 86DOS 0.86/MSDOS1.25/MSDOS2.00 system on DSDD 8"
> floppies with 9 1K sectors per track. I thought I was very cool for
> doing this (cringe)).
>
> The short of it is, if you have a CP/M system with a WD controller, you
> can write nice dumb code to do a 'track dump' if you have enough memory
> or a sector dump if you don't and see what's electrically on the
> diskette.
>
> I wish I had all my old data. I used to pore over floppy track dumps and
> could read the MFM header (it's easy) to determine all sorts of stuff.
> It's not mysterious, just obscure.
>
>
Received on Mon Nov 03 2003 - 15:06:49 GMT