Date   : Mon, 16 Apr 1984 11:46:59 EST (Monday)
From   : Tom Reid <treid@Mitre-Gateway.ARPA>
Subject: 8086 co-processors for CPM80

I am considering adding an 8086 co-processor to my CPM80 system
(Ithaca 525; Z80B, 128K, 2-5 1/4" and 2-8" drives).  HSC, Herkimer,
NY (see add in April '84 Microsystems, p. 16) has one.  Their latest
brochure lists an 8086 processor board with 256K ram, MS-DOS 2.11,
8 bit ram disk, Z80 interface, documentation, enclosure, and power
supply for $775 retail.  Other options such as 68000, CPM86, and a
(SOON) IBM compatible bus are available.

The system boots up as (1) of old, (2) CPM80 with a 256K ram
disk, or (3) MSDOS/CPM86 using the CPM80 for all non-ram I/O.
Sounds like a way to get both a ram disk and a 16 bit processor
without throwing the old system away if . . .

I would be interested in hearing from anyone who has experience
with this or other co-processors.  In particular, what are the
bonuses, problems, or gotchas.  For example, could the Z80 being a
ribbon cable away from its old CPU slot cause problems or is the
8086-back-to-CPM80-for-I/O going to be too slow?  The people at HSC
say that the system can be installed in 15 minutes.

I will edit and keep updated any responses to those interested via
the net.  Thanks.  Tom Reid at MITRE Corp., McLean, Va.

ps - I am interested in buying an Ithaca 64K ram board.