Date   : Thu, 02 Feb 1989 09:49:51 PST
From   : rzh@freedom.llnl.gov (Roger H. Hanscom (415) 423-0441)
Subject: Z80 Co-processors

Does anybody out there have any experience with Z-80
co-processors of the type that plug into the PC buss??
I know that there are (were?) several on the market,
and I remember seeing a review comparing some of them.
As I remember the review found quite a disparity
between them with respect to ease-of-use/quality, so
I imagine it would be a good idea to check on this.

I got a catalog in the mail last night from Central
Computer Products.  The co-processor that they carry
is "UniDOS".  It runs a Z-80 at 8 MHz.  How do these
things communicate with DOS over the buss?  What is
the software like?  How does one run CP/M on the Z80,
or is that done??  In other words, how does CP/M on
the co-processor access the PC hardware (disks)??
The UniDOS device is on a half-card, and costs $175.

Please don't suggest things like Z80MU or the V20 in
8080 emulation mode.  I like Z80MU, however it is
**VERY** slow.  I don't really like the 8080 restriction
of the V20 ... I run a **LOT** of Z80 code.

     Roger       rzh%freedom.llnl.gov@lll-lcc.llnl.gov


End of INFO-CPM Digest
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