[stella] 6502 question

Subject: [stella] 6502 question
From: emooney@xxxxxxxxxxxxxxxx (Erik Mooney)
Date: Fri, 04 Apr 1997 06:58:53 GMT
Question for you 6502 gurus (both of you =) ).
Suppose I have a number between $90 and $9F stored in $80.  What's the
fastest way to get the number at the address in $80 into the accumulator?
(that is, if the value in location $80 equals $94, I want the accumulator
to have the value in $94.)

It looks like I need to zero Y and then do LDA ($80),Y which is indirect
indexed for 5 cycles plus clearing Y, or zero X and then LDA ($80,X) which
is indexed indirect for 6 cycles plus clearing X.  These would work on the
zero page, right?  Would the "zero page-ness" decrease the number of cycles
as it does for direct addressing?

Thanks again to everyone for the help I've gotten with this project.

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