Re: 16-bit 6502 replacement bulk order : PCB schematics

[mjmahon@aol.com (Michael J. Mahon)]

Rubywand wrote:

>The 65C802 never attracted much interest because the
>chips available at the time of introduction offered no great
>advantage vis-a-vis the 65C02 and because interest focused on the
>65C816.
>
>     Besides, you didn't have any really fast 65C802's. Anyone thinking
>of a reasonably simple performance upgrade back then would have gone for 
>one of the 6502- or 65C02-based accelerators. 
>
>     A 65C816 board is interesting because the 65C816 is better than the
>65C802 and it's the uP that actually got used-- e.g. in the Apple IIgs
>and accelerators. So, along with having fast 65C816's to plug in, there
>is a lot of 65C816 software around.

I thought that the 65C802 was _exactly_ a 65816 with 65C02 timings
and a 16-bit address bus.  So, unless you have a plan to use the
eight extra address bits of the 65816, what's the advantage?

Put another way, the 65C802 should run all the 65816 software
that fits in 64KB.

And if you want to directly address more than 64KB, you'll have
to plug much more than a processor and a couple of glue ICs into
the processor socket of an 8-bit Apple II, regardless of the model.

-michael

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