Yay, now I need some Osborne boot media!

Fred Cisin cisin at xenosoft.com
Mon Nov 24 11:04:28 CST 2014

> >> sit, I don't even have a PC with a 5-1/4" drive installed, if (and that's
> >> +if+) it were capable of writing discs for the Osborne format.
> >If you have any serious intentions of vintage computer collecting, this
> >is a must have.

On Mon, 24 Nov 2014, Peter Coghlan wrote:
> Isn't "must have" a bit strong?

A little.  Maybe a "strong recommendation".
He would need a PC with a 5-1/4" drive for running XenoCopy.  (Or Chuck's
software.  Or David Dunfield's software.),
OR, he could write a PC emulator for something else that he owns.
(XenoCopy could read Osborne1 DD disks while running under "Transformer"
on Amiga 1000, . . . )
OR, once he gets the Osborne into a monitor program, and or booted and
running DDT or other tools, then he could simply write the software needed
to use the Osborne to be his creator of 5.25" disks.  (A PC emulator
running on the Osborne might not be practical, particularly for current

> Maybe I'm more of a vintage computer user than a collector or maybe I'm just
> not serious but a VAXstation 2000 and a BBC Micro have managed to cope with
> all of my 5-1/4" disk needs so far.  As far as I'm concerned the hobby is
> about what can be done without resorting to a PC, not what can be done with
> one as a prerequisite or as some kind of fallback to be used for
> routine tasks.

I'm not aware of any software currently extant for using Osborne for
disk manipulation, but it would certainly be capable of it.

After all, "boot" in our business is short for "bootstrap", which is based
on Baron Von Munchausen lifting himself out of the swamp by pulling up on
his own bootstraps.  Just because the tools aren't there doesn't mean that
you can't write them; just because the tools to write the tools aren't
there doesn't mean that you can't write them; just because the tools to
write the tools to write the tools . . .

> Now back to the regular religeous war on US vs European power distribution
> (which I have strongly held opinions on too but I don't think it's going to
> do much good to voice them, especially when each mail seem to be arriving
> twice until the list gets back to normal...)

Well before we get back to griping about how the list is not as perfect
as it once was, . . .
Elsewhere in another branch of this thread, there is mention of certain
limitations of the PC hardware, including the difficulties with Single
Density, and with 128 byte sectors in Double Density.
I love that discussion, because 30 years ago, I spent a ridiculous amount
of time convinced that I was doing something wrong when I was trying to
read 128 byte sectors.  It is such a relief to find out that, besides the
many things that I was doing wrong, that the problem was actually stuff
that others had done wrong before me.   Sure woulda been nice if I had
known Chuck THEN!  (I had finally figured out why I couldn't do single
density by staring at pin 26 of the NEC765 in the schematics in the IBM
PC Technical Reference Manual.)

The flamewar about RX02 is based on defining what is meant by the phrase
"MFM floppy"!  Nobody is "wrong", they just aren't recognizing each
other's definitions.  The RX02 is NOT an "FM floppy"; the RX02 is NOT an
"MFM floppy".  It is a hybrid.  It took an FM low level format, and
rewrote the data area of each sector with MFM, resulting in a disk that is
about 1/3 FM, and 2/3 MFM.  In terms of the floppy ITSELF, disks rated for
FM or rated for MFM should both work, but there might be better
reliability using the MFM rated disks.  AND NOT the 600 Oerstedt "1.2M"
disks!  THOSE might seem to work, but will be blank again before you need
to reread the disk!   BTDT.
And, NO, the 765 can't be tricked into reading RX02.
Or can it?  PROVE ME WRONG - write the code to do it!

But, lest we forget,  . . .  the OP wants Osborne disks.  The PC has no
major problems reading, writing, and formatting DOUBLE DENSITY Osborne
disks [with appropriate software - you shoulda bought a copy of XenoCopy
when it was available, to keep me in business, and to write Osborne disks
for the OP]

IF the OP wants SINGLE DENSITY Osborne disks, as were used in the original
Osborne Computer (before it had a number), they are NOT 128 byte sectors,
just a fairly ordinary single density (FM) 256 bypes per sector with 10
sectors, which can be done with TRS80, or with a PC with certain specific
FDC chips, OR a PC with certain [minor] modifications (go stare at pin 26
of the FDC in the schematics!) such as what Flagstaff Engineering did to
the original IBM FDC board.

OK, NOW back to the list meta-discussions, "which was the first computer?",
cars, guns, and storage space.

Grumpy Ol' Fred     		cisin at xenosoft.com

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