Subject: [stella] Loops with two counters From: "Bob Montgomery" <BobM@xxxxxxxxxxx> Date: Thu, 7 Jul 2005 15:26:56 -0400 |
Hi all, I am writing a kernel that uses Y to count scanlines but also uses X to count down as well. So, the looping code looks something like this: dey ;+2 50 tya ;+2 52 cmp BlockChange,X ;+4 56 bne Kernel1Loopa ;+2 58 dex ;+2 60 bpl Kernel1Loopb ;+3 63 That takes 15 cycles. Is there a faster way? I really need a few more cycles :) Thanks, -bob Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://stella.biglist.com
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