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Re: Upgrading TWGS; Need GALs
Thanks to everyone for the help. It has been determined that I do NOT
need new GALs, because they are not required by new (post-1992) WDC
65c816 chips. Here's an explanation of why:
Todd Whitesel discusses which instructions the GALs slowed down
that don't need to be anymore with the new 65C816 chips:
toddpw@ugcs.caltech.edu (Todd P. Whitesel) wrote:
>>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.
And also for more documentation, visit this URL:
http://ground.isca.uiowa.edu/apple2/apple16/Hypermedia/Hypercard/
and download TWGSupgrade.SHK or TWGSupgrade.BSQ from the list of
files. This is a stack that will tell you, among other things,
where to get the source of the ROM upgrade. If you don't have
HyperCard IIGS, the runtime player is available from this list as
HCGSPLAYER.SHK (it lets you run, but not create, stacks).
So thanks to everyone who helped. I hereby terminate this thread, unless
someone wants to add any other thoughts or comments.
-=Toasty=-
--
-ToasterKing-
ToasterKing @ mindless.com
Remove spaces from the above address to reply. Duh.
This message was posted on a Macintosh with Nuntius 2.0.4, if anyone
cares.