Date   : Wed, 13 Jul 1983 18:19:41 EDT (Wed)
From   : Mike Ciaraldi <ciaraldi@Rochester.ARPA>
Subject: Re: Non-Heath 8" disk drives on H-100/Z-100 systems

I am using a Shugart 851 and a CDC drive, both 8-inch and double-sided,
on a Z-100. They work OK, under both CP/M-85 and ZDOS.
However, occasionally they don't; I will get a seek error, especially
on FORMAT. Usually rebooting fixes this up.  This problem is only on the
Shugart, not the CDC.
I tried changing the step rates under CP/M and ZDOS using the info in the
Zenith manuals. This fixed up the CP/M-85, but not the ZDOS.

This caused me to find out about ANOTHER problem. The MAP command
on ZDOS 1.1 will not let you declare a drive imaginary, so it can
share a physical disk with another drive.
I called the Zenith hotline and they mailed me a new version.
This works, except now there is no way to make a drive un-imaginary.
There is no switch for it, and MAP/Z, which is supposed to reset
the drive configuration, does not affect imaginary drives.
I called Zenith back and they said it is supposed to work this way.
Mike Ciaraldi
University of Rochester