Re: Sudoku puzzle solver for Apple II

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

Chris Alaimo wrote:
> By your logic, no one should ever write an Apple II program using 65c02
> language because then not every A2 owner can run it.  How many Apple II
> enthusiasts do you know that don't have AT LEAST one 65c02-equipped
> Apple in their arsenal?  I think I only have one Apple II that DOESN'T
> have a 65c02 in it (or a processor capable of running 65c02 code).

Although it may sound strange, I think I might try to make exactly
that argument.

In the vast majority of cases, the 65C02 operations bring almost no
advantage to the resourceful programmer, while limiting the "market"
for his product by a significant fraction.

Only when rigid space or time constraints require it would I plan
on using 65C02 ops, and I can count the possible cases on one hand.

It seems to me that the 65C02 extensions were "too little, too late".
They provided a very small advantage in very few cases and at the
significant cost of creating a completely avoidable compatibility
problem.

When an architecture, warts and all, has been around long enough to
be widely exploited, and everyone has learned to live with it, it
doesn't make any sense to make *minor* improvements and break
unconditional compatibility.

As long as there are *any* 6502 Apples out there, that is an overriding
reason to write to the 6502, especially since the cost for doing so is
so low.

In the case of the Sudoku solver, a 30-second full solution is
increased to 30.17 seconds to remain completely compatible!

-michael

Fast Sudoku solver for Apple II's!
Home page:  http://members.aol.com/MJMahon/

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