Re: 68008 co-processor board complete working design available ...

[Jim Gilbert <brokerjim@gmail.com>]

On Nov 9, 7:51 am, Steven Hirsch <snhir...@gmail.com> wrote:
> On 11/08/2010 07:57 PM, Michael J. Mahon wrote:
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> >> I am seriously thinking of scanning and loading all this stuff into a
> >> web site and making it public domain if anyone is interested.
> >> As far as I can tell the 68008 and the 68901 and the 4501s are still
> >> all available. The rest of it is all 74 series TTL except for one 555
> >> timer chip.
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> >> My design, was heavily influenced and inspired by the Motorola design
> >> note but is clearly significantly different and original.
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> >> The main problem with building another one or more would be finding a
> >> viable Apple II prototyping board that is big enough.
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> >> The 68008 software is assembly language in the AT&T syntax that was
> >> accepted by the BSD UNIX system at work and the public domain 68K
> >> assembler for CP/M I used on my Z/80 coprocessor (Softcard, then
> >> Applicard). Yes, the 68008 co-existed with the Z/80 cards...
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> >> I no longer have an Apple II. In order to build or play with one of
> >> these a bus extender is very valuable because you'll wear out your
> >> backplane slot with too many insertions and extractions otherwise...
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> > Jim, I'd be very interested in your design. It is considerably more
> > capable than the 68008 card I acquired several years ago! That card
> > had a single 8-bit port, with handshaking--pretty slow communication.
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> > I think it would be a great idea to scan in the documentation and make
> > it available on the web.
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> Particularly because all the logic will probably fit on a single CPLD.  Might
> be a reasonably simple thing to build.

I strongly suspect all the SSI/MSI would handily fit into a CPLD or
FPGA.  My work on this whole kit was seriously compromised long ago
when I realized I had bet on the continuing existence of long Apple II
prototyping cards and that they had ceased to exist.