Re: co processor board for a2's

[CUTblakeney@home.com (Jeff Blakeney)]

On Thu, 06 Apr 2000 02:20:31 -0500, Phoenyx <quazar@dcnet2000.com>
wrote:

>What exactly in the GS is capable of taking advantage of the
>benefits of a co-processor? Most programs I know of would have to
>be re-written to take advantage of it. I know this was considered
>for the 65816 cpu, but AFAIK it was never developed properly.

It would be trivial to patch the SANE tool set (and the Integer Math
tool set if it would provide any benefit) to have them call the
coprocessor to get the result.  I believe even the 8 bit SANE
environment can be patched as well.

This means that any program that uses those patched tool sets will
benefit from faster math routines.  This should include programs like
AppleWorks Classic and AppleWorksGS (spreadsheet module recalculating)
and Animasia (to speed up rendering times) to name three
possibilities.

>Unlike the current crop of PC compilers which supply routines to
>use in the case that no co-processor exists, the Apple II series
>never had that luxury, thus by itself the co-processor is useless
>except for new projects.

Unfortunately, you are right in that many Apple II programmers wrote
their own math routines instead of using the tool sets so those
programs won't automatically benefit.  However, if the source can be
updated either by the original programmer or someone else and
recompiled, it will gain the benefit.  Even if the source isn't
available, some of those programs can be patched to get at least some
benefit.

Then, like you say, new programs will benefit as well because the
programmers would then know that they should either always use the
tool sets or have a setting to switch between their own math routines
and the tool set routines to give the best performance to people
regardless of whether they have a coprocessor or not.

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