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Re: [N8VEM-S100:1069] A new S-100 6502 CPU Board



See:  http://sbc.bcstechnology.net/  "This site documents the design
and construction of a homebrew computer, dubbed POC (Proof-Of-Concept)
and powered by the Western Design Center's W65C816S microprocessor
(MPU)."

On Mon, Aug 20, 2012 at 10:49 PM, David Riley <frave...@gmail.com> wrote:
> On Aug 20, 2012, at 21:48, "Andrew Lynch" <LYN...@YAHOO.COM> wrote:
>
>> Hi!  At this point since the W65C816S is an 8/18 bit chip I would suggest a
>> 16 bit S-100 CPU board built around it.  Then the board could use the
>> S-100/IEEE-696 16 bit extensions and be purely 16 bit rather than tweaking
>> the S-100 6502 CPU V2 board which is a fundamentally 8 bit CPU design.
>
> My memory of the 65c816 is a bit rusty, but isn't it only an 8-bit data bus with an ALE equivalent pin to latch the upper 8 address bits from the data bus?
>
> I'm thinking that might make it difficult to make a true 16-but board out of it; I seem to recall that the primary benefit of the 65C816 was that it behaved as an 8-bit CPU to the outside world (much like the 8088 as opposed to the 8086).
>
> Or I could be remembering completely wrong. Either way, I'd be interested in a 65C816 CPU board!
>
>
> - Dave