[comp.os.cpm] Osborne 1 diskdrives. Help needed.

jonas@fy.chalmers.se (Jonas Hvarfner) (03/03/91)

I have an Osborne 1 with diskdrive problems.

If I format a disk with 22DISKs cfmt in an IBM PC, the B-drive on the
Osborne refuses to read it. I get "bad sector"-errors each time I try
a DIR B: or a TYPE B:TEXT.FIL (the file is written by 22DISK). If I
use COPY to copy the entire disk to another in the A-drive, it reads
up to about track 30-35 and then says "read error".

However, the Osborne does not complain whatever I do with this cfmt-
formatted disk as long as I do it in the A-drive. I can read and write
without any problems at all. The A-drive also reads and writes disks
formatted and written on in the B-drive. The B-drive sometimes, but not
always, complain about A-formatted and -written disks.

I have tested this on the Osborne at several times with new disks and
using different IBMs, always with the same disappointing result.

It's very annoying not to be able to trust the B-drive. Therefore
I would be very happy if someone could comment on the causes of this disk-
drive behavior. What can I do about it? If it is misalignment, can I align
the drives myself? If so, how? (I have access to an electronics lab with
oscilloscopes, frequency-counters etc.)

                                      Thank you!

                                      Jonas Hvarfner
                                      jonas@fy.chalmers.se

CHARLES.COTHAM@f601.n106.z1.fidonet.org (CHARLES COTHAM) (03/03/91)

Jonas,
 
   I don't know if it would help, but I have a couple of articles on disk 
drive alignment for the Osborne 1. I would be glad to make a copy and 
send to you if you will leave me an address. 
 
                          Charles Cotham
                          2205 Lilac St.
                          Nederland, Texas
                                      77627