Re: 65c816 in a IIc

["Michael J. Mahon" <mjmahon@aol.com>]

David Empson wrote:
> Warren 'Llama' Ernst <wernst@gmail.com> wrote:
>
>
> > On Apr 19, 6:02 pm, gids...@sasktel.net wrote:
> >
> > > > That somehow adding a 65816 added "efficiency" to your computer,
> > > > somehow. There were less than 10 8-bit programs that could take
> > > > advantage of that chip, and I don't think any of them had anything to
> > > > do with AppleWorks.
> > >
> > > Do you happen to have a list of those programs, Warren?
> > >
> > > Rob
> >
> > Rob,
> >
> > Sorry I don't. I'm just recalling a conversation I had about 20 years
> > ago.
> >
> > The only program I remember right now is the Merlin 816 assembler,
> > which could somehow take advantage of the chip.
>
>
> Merlin 16 (which runs in ProDOS-8) requires a 65802 or 65816 processor.
>
> If you have an 8-bit Apple II with a 65C02 or 6502, you are limited to
> running Merlin 8. Installing a 65802 would let you run Merlin 16.
>
> The main advantage of Merlin 16 over Merlin 8 is it is assembles about
> five times faster. This is because it can use the native 16-bit
> processor instead of Merlin 8's method of doing 16-bit calculations via
> Sweet 16 (which is a virtual processor implemented in 6502 machine
> code).

There's a fine example of how spending a couple hundred bytes on fast
in-line 16-bit arithmetic in just a couple of dozen most frequently
used places would buy a good part of that 5x improvement on a 6502!  ;-)

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

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