Date   : Wed, 16 Feb 1983 13:22:21-PST
From   : CCVAX.gil@nosc-cc.arpa
Subject: Re: Godbout CPU68

Compupro stuff is indeed quality S-100 gear, and it seems to be very
reliable.  We have the 8085/8088 cpu board, the disk1 floppy controller,
the ram 21, and the system support board.  It all worked the first try.

On the negative side, the disk 1 has a bad feature in that it unloads
the drive heads very very frequently.  If you have become used to a
properly done system which lets a number of revolutions go by before
unloading the head, the compupro system will annoy you greatly.  If
flaps the heads up and down incessantly, and as a result, it introduces
delays that make it run considerably slower.  For example, a Z80 runing
at 4 MHz with Jade controller runs a particular disk-bound program
in 11 mins and 15 seconds.  The compupro running the 8085 at 6 MHz
runs the same program in 14 minutes and 47 seconds.  It OUGHT to be
faster due to the faster cpu clock rate, but is much slower due to
the idiotic way they handle the head loading.  The worst part, though,
is the noise of listening to the thing beating its brains out.

Godbout is well aware of the problem, and will only say that the 
next version of the disk 1 will have it fixed.

They claim to be working on an automatic cpm86/cpm80 switching
scheme similar to G&G engineering's MPM8-16 which will make the
8085/8088 board much easier to use for those of us who need to
use both systems while developing software for the 8086/88.  Tis
said to be ready in a few weeks.  The G & G scheme really works very
well, and saves a lot of disk changing.  You can use all your old
favorite 8-bit tools, like wordmaster, for general work, then
automatically run the 16-bit stuff.  They use the difference between
.COM and .CMD file names to do the switching.  If godbout does as good
a job as g & G did, it will be nice.
Good luck.
-gil