Re: Transwarp GAL chips

[toddpw@ugcs.caltech.edu (Todd P. Whitesel)]

"no1inParticular" <compuser@prodigy.net> writes:

>It says that the GALs were needed to slow the processor down for certain
>operations, because the chips weren't very good.

I think that was because the REP and SEP instructions turned out to require
a really hideous signal wire stretching across most of the chip (on WDC's
layout, anyway) -- as you overclocked the 65816 more and more, REP & SEP
would croak first, and then later on all sorts of stuff would fail (i.e.
hang city).

Probably if it hadn't been for REP and SEP, WDC would have gotten faster
chips working a heck of a lot sooner, quite possibly changing history.

If the modern 65816's are a new layout, then I'd expect the REP/SEP problem
to be a non-issue for them -- and unless there were other features in the
GALs, it would seem to be sufficient grounds to update the FAQ.

Todd Whitesel
toddpw @ ugcs.caltech.edu