Date   : Fri, 28 Oct 1988 09:10:00 EDT
From   : RLH <HAAR%gmr.com@RELAY.CS.NET>
Subject: z80 replacements, S-100 single board computers

I am considering upgrading my S-100 Z-80 computer with a replacement
CPU board using either the Hitachi HD64180 or the Zilog Z280 so that
I can run my current CP/M programs. I have a couple of questions and
would appreciate any information anyone can share.

1) Are the Z280 and HD64180 trully object code compatible with the
Z-80 ?

2) In what ways are the Z280 and HD64180 different?

3) I would like to run a version of the Z system (ZCPR & ZRDOS)
that takes advantage of the larger address space of these chips.
Are there implementations available?

4) Does anyone have experience with particular boards that they
could comment on ?


The feature set that I am looking for is:

    - S-100 board.
    - at least 12Mhz CPU.
    - on board RAM, either static or dynamic but fast and rock solid.
    - 2 serial, one parallel port.
    - floppy disk controller for 8 inch drives minimum, with
        support for 5 1/4 desirable.
    - ROM firmware with monitor program and low level I/O drivers.
    - can access off board memory and peripherals using
        standard S-100 addressing.
    - supports S-100 multi-mastering and DMA transfers to on-board
        memory.
    - SCSI or hard disk controller - optional, but nice
    - clock/calendar ahrdware with backup battery.
    - ZRDOS or CP/M 3.0 software available.

If you can recommend specific products that match this description,
please let me know. The only one I have found so far is a Z280
single board computer from a company called Computer Design
Solutions, Inc. in Statesville, NC, phone: (704)876-2346. It sounds
good but technical info is meager and the board is currently
vaporware - in production around the end of the year (which year?).
They are quoting a price of $550 for the board with 128K RAM.
I have not heard of this company before. Does anyone have any experience
with them?

- sorry if this request got long winded, but I would really
  appreciate any advice.


        Bob Haar
        CSNET: HAAR@GMR.COM


End of INFO-CPM Digest
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