Subject: [stella] Indirect Why? From: "Ruffin Bailey" <rufbo@xxxxxxxxxxxxx> Date: Mon, 6 Sep 1999 12:24:20 -0400 |
Ok, I've been pouring over my code a bit _too_ long I suppose. I just can't get indirect y to work the way I'd like. I've got some bytes at the end of my demo that I'd like to use as the player graphic. I'm setting those up like this: ORG $FF01 .byte %10101010, %01010101,%10101010, %01010101 Then in earlier in my demo, I'm assigning this position to two bytes in RAM like so: LDA #$00 STA CTRLPF ;================================================= ; setting up where the player graphics are located ;================================================= STA $90 ; zero LDA #$FF STA $91 ; FF + 00 = FF00 (used with an indirect Y below) Now 90 should be the LSB and == #$00 and 91 should be the MSB and == #$FF, correct? Just one byte away from where I want to grab my graphic info. So during the screendraw, I've got this code to do just that: LDY #$01 STA WSYNC LF0AD: INX CPX #$60 BEQ DrawThePF LDA $90,Y ; "FF" + "00" = FF00; FF00 + Y = FF00 + 1 = FF01 STA GRP0 INY STA WSYNC CPY #$10 BNE LF0AD Did I screw up somewhere? Let me just say it's not working... I get one scan line worth of player, and that's it. Thanks for the help, and sorry if this is such a simple matter it's embarassing. I'll slap the full code up at: http://members.aol.com/mactari/why.asm Thanks again, Ruffin Bailey -- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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