Re: 18 Mhz IIgs?

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

Rubywand wrote:

>     On a IIgs, getting up to 16MHz could happen with someone using a newer
>version of the 65c816 on a TransWarp-GS or ZipGS accelerator board equipped
>with a 64MHz oscillator module and faster than usual RAM and, possibly,
>higher-speed versions of one or two 74xxx IC's.
>
>     The main limitation seems to be that (besides RAM) the IC's and other
>components on the accelerator boards do not all perform correctly as you push
>the speed. Layout of traces could also be a limiting factor. Since some
>boards handle a speed boost better than others, it's hard to come up with
>reliable speed upgrade cookbooks.

I thought that all IIgs accelerators depended on PALs, which have
speed limits, and cannot be replaced by faster chips because their
logic is not documented.

I would expect that after everything else is speed-upgraded, these
chips would remain as the fundamental limiter.  And I'm sure that
there are faster ones and slower ones--they only had to pass the
original acceptance test.

-michael

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