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. -- Archives available at http://www.biglist.com/lists/stella/archives/ E-mail UNSUBSCRIBE in the body to stella-request@xxxxxxxxxxx to be removed.
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