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Re: Proterm and the //E
- Subject: Re: Proterm and the //E
- From: nparker@cie-2.uoregon.edu (Neil Parker)
- Date: 1996/06/30
- Newsgroups: comp.sys.apple2
- Organization: University of Oregon Campus Information Exchange
- References: <4qvndj$38f@news.vanderbilt.edu> <4r2fm4$gr1@pith.uoregon.edu> <4r56je$fpm@wraith.cs.uow.edu.au>
In article <4r56je$fpm@wraith.cs.uow.edu.au> david@wraith.cs.uow.edu.au
(David E A Wilson) writes:
>nparker@cie-2.uoregon.edu (Neil Parker) writes:
>> IF PEEK (64435) = 6 AND PEEK (64448) < > 234 THEN PRINT "Mousetext
>> is probably available."
>
>>The above line is also sufficient to distinguish if the CPU is a 65C02 (or
>>better), since all ROMs that pass that test make use of 65C02 opcodes.
>
>This is incorrect. The enhanced //e ROMs, despite coming with the 65c02 chip,
>do not use any non 6502 instructions. I have run a //e with a 6502 and enhanced
>ROMS without problems (other than software which requires 65c02 instructions).
>It is a fairly safe bet however.
Ack. I was afraid of that. The possibility did occur to me, but not until
several hours after I posted.
I guess the lesson here is don't rely on the ROM version to tell you
whether or not a 65C02 is available. Do one of the guaranteed-foolproof
checks instead, such as testing for the 6502 decimal mode bug.
- Neil Parker
--
Neil Parker, nparker@{cie-2,cie}.uoregon.edu, http://cie-2.uoregon.edu/~nparker
"Bad move, Neil!" -- The Tick