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Re: Bored at work....

On Tuesday, August 7, 2012 10:30:16 AM UTC-7, Antoine Vignau wrote:
> I knew I should have written it yesterday!
> 
> I meant tiles and scrolling should be one/two byte(s) movement

********
*
* SHIFT THE HGR SCREEN ($2000) ONE BYTE TO
* THE LEFT, DESTROYING BYTE ON LEFT
*
*  BY RICHARD JACKSON, AUG 2012
* FOR RICH12345.TRIPOD.COM FOR PURPOSES OF
* ANIMATING SUPER MARIO BROTHERS!
*
************************

         ORG   $5FE0

SLO      EQU   $06        ; screenline address
SHI      EQU   $07

THI      EQU   $7000      ; y lookup table
TLO      EQU   $70C0


         LDX   #0         ;START AT TOP
VERTLOOP LDA   TLO,X
         STA   SLO
         LDA   THI,X
         STA   SHI

         LDY   #1
HORZLOOP LDA   (SLO),Y    ;GET SCREEN
         DEY              ;MOVE IT TO LEFT
         STA   (SLO),Y    ; PUT it on screen
         INY
         INY              ;move to right one byte
         CPY   #41        ;done with whole horiz line?
         BNE   HORZLOOP   ;nope
         INX              ;yep, go to next vert line down
         CPX   #191       ;done with all vert lines?
         BNE   VERTLOOP   ;nope
         RTS              ;yep