Date   : Tue, 31 Mar 1987 09:41:16
From   : hanscom@lll-es-s05 (Roger Hanscom 423-0441)
Subject: CP/M under MSDOS

>Has anyone heard of any programs which allow you to run CP/M 2.2 pro-
>grams under MS-DOS on PC's.  I found one which was supposed to emulate
>a Z-80 and CP/M 2.2 on GEnie, but it does not work.  Are there any
>others out there?

There are a number, but the best one I've found is called "Z80MU" by
Joan Riff of ComputerWise Consulting Services, P. O. Box 813, McLean,
Va. 22101.  It is available from a number of "public domain copying
services" for $3-$6.  Check out the ads in Computer Shopper (esp. the
last 50 pages).  Computer shows are another excellent source of pd
software.  
I got a catalog from MicroCornucopia (P. O. Box 223, Bend, OR 97709)
last night, showing a pd disk (MS-DOS#22) with a CP/M emulator that
makes use of the V-20 subset of 8080 instructions to run 8080 CP/M
stuff.  They ask $8 per disk for non-subscribers, and $6 otherwise.
The emulators that use the 8088 instruction set (like Z80MU) are slow
because they execute many 8088 op codes to emulate one Z-80 op code.
Z80MU claims to match the performance of a 1MHz Z-80.  The V-20
emulators are faster because they execute 8080 op codes as a part of
their instruction set, but they limit you to programs written for the
8080.
Get a copy of Z80MU and try it out.  I use it on a clone, and it works
just fine.  If you can't locate a copy, contact me and we can arrange
to copy it for you, however I'm not set up to be able to make lots of
copies.

                         ---Roger Hanscom---