Subject: [stella] Brick wall ahead From: Pete Holland <petehollandjr@xxxxxxxxx> Date: Sun, 24 Oct 1999 10:53:12 -0700 (PDT) |
I'm slowly but surely programming, but I need some help. Specifically, a branch for zero. I'm need the computer to comare a number in RAM with zero and branch if is 0, otherwise just keep steamrolling ahead. Now, the questions: 1) How do I control the zero flag? I see CLC (CLear Carry), CLD (CLear Decimal), CLI (CLear Interupt), and CLV (CLear oVerflow), but nothing like a CLZ (CLear Zero). Is there a command to do it and it's just not listed in this book? Or do I pull the byte for the flags into A, AND it to turn off the zero flag bit, and STA it back in RAM? 2) Is this how I'm supposed to do this: Somehow clear the zero flag LDA the number I want to compare into A, do whatever it is I need to with it there. CMP #$0 BEQ to the end of where the commands for no-zero are (no more that 127 bytes) Clear zero flag, do next comparison, etc. Any help will be appreciated. This is taking longer than I expected. ===== __________________________________________________ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com -- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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