Date   : Fri, 17 May 1991 09:59:04 GMT
From   : olivea!samsung!munnari.oz.au!comp.vuw.ac.nz!actrix!ewen@apple.com (Ewen McNeill)
Subject: Osborne 1 - Questions

Hello Netlanders.

I have been given an Osborne 1 (to go with my other CP/M machines).  I
was rather lucky that I got the original disks (and some others) with it
(but not manuals) and all for the price of nothing....  

However, I have some problems and some questions.   First, a bit about
the machine.  An Osborne 1, with double density drives, a rom which
states something like: 7A8007-00 Rev A D7AC OCC. There may be more roms,
etc... I didn't go looking around much.

I also got three "original" looking disks - CP/M 2.2, System and
Utility, CBASIC/MBASIC, and SUPERCALC.  A small number of other disks
came with the system, a lot of them backups/modified versions of the
above.  I think there is also a copy of WordStar somewhere in there.

Anyway, the problems:  1.  B drive refuses to read disks.  It complains
that the disks are unformatted (they are formatted, they work on drive
A).  I have taken the machine apart and looked at the drive, but I
didn't spot anything in my quick inspection that looked wrong. The
select lines make it to the right chips etc.  I ran out of time to check
the R/W data lines.   I would appreciate any suggestions that people
have for why this doesn't work and/or what to check next.  Oh, BTW, I
have tried cleaning the disk heads.   Also, if it is of use, I have an
old (5.25 Double sided, Double Density) IBM disk drive (full height, 
even... :-) -- would this work in its place?

And the next one:  2.  I have very little documentation.  Not that CP/M
itself is a problem (I have been using it for several years), but the
specifics of the Osborne are.  I know enough about the disk format to be
able to get stuff from my other machines to it, but I don't know
anything about the pinouts of the various connectors on the machine. I
presume the one labeled RS232 is pretty standard....  although I seem to
remember hearing something about it being slightly strange.
 
The modem port looks interesting -- can anyone tell me the pin outs.  I
will pull a copy of the Mex overlay for the Osborne off our Simtel
mirror (a year or so out of date, but still lots of nice stuff), and get
that going.  But that still leaves the physical cable details to
determine.  I can use a soldering iron... :-)

Thanks, in advance, for your help.   Replies by mail, or in this group.
Either should get to me pretty quickly.

-- 
Ewen McNeill, ewen@actrix.gen.nz