Re: Sudoku puzzle solver for Apple II

[pausch@saaf.se (Paul Schlyter)]

In article <NpidnWmquZS-5ijZnZ2dnUVZ_qOdnZ2d@comcast.com>,
Michael J. Mahon <mjmahon@aol.com> wrote:

A 6502 assembly language programmer using 65C02 specific ops would be
compared to one who uses an original 6502 and there utilizes the
undocumented 6502 ops which certainly will fail on a 65C02.  And for
the same reason: marginal speed and space advantages.


> 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/
> 
> "The wastebasket is our most important design
> tool--and it's seriously underused."

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