Junkbox CP/M system?

[Allison]

>
>Subject: Re: Junkbox CP/M system?
>   From: "Chuck Guzis" <cclist at sydex.com>
>   Date: Tue, 24 Apr 2007 11:07:20 -0700
>     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 24 Apr 2007 at 10:12, Allison wrote:
>
>> At a minimum.  FDC interfaces are more involved as the interface has to 
>> include data and drive interfaces unless one can find a chip like 2793
>> or 37C65.
>
>My personal favorite is the WD1770/1772 series.  It doesn't do 
>500Kbps drives (no big deal for CP/M); interface logic is very 
>minimal.  Very simple to program; a 4MHz Z80 should be able to keep 
>up with the data transfer without breaking a sweat. And it fits in a 
>reasonably small (28 pin) DIP package.
>
>But a minimal system might incorporate nothing more than a PIIO or 
>SIO and simply pass mass-storage requests and console I/O over the 
>same path to a PC using a formatted message scheme.   Makes the CBIOS 
>coding a walk in the park.

If the system is 32k eprom with shadow, 1770/72 SIO, CTC and 64k of ram
it's called a AmproLB. ;) Great little system on a board. the LB+ adds a
5830 SCSI interface and that makes SCSI hard disk possible.

>Or, one could build the Z80 onto a PC prototype board with its own 
>local memory as a coprocessor and conduct mass storage and console 
>I/O over a pair of I/O ports.  For many, that may be the best of all 
>worlds as it relieves one of the problem of terminal and disk 
>interfacing, power supply and enclosure.  Of course, the folks who 
>want to put their project into a mahogany case with glass front may 
>not be taken with this idea. :)

That would be identical to the DecmateII (and III) CP/M APU board.
the board is a Z80, 64k of ram and two ports.  The DECmate does disk 
and display work for it.  The Z80 APU for the PRO350/380 is similar.
It's been done more than once on the ISA bus (PC).

As to the wood and glass case.  Anything fits inside that! ;)



Allison