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53 lines
877 B
ArmAsm
53 lines
877 B
ArmAsm
; shimmery blue pattern
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; X=48 here, can't count on others
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staggered:
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stx FRAME ; set FRAME to 48
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ldx #$00 ; init X to 0
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stx GBASL ; set GBASL to 0
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; pulse loop horizontal
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outer_loop:
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lda #$40 ; reset GBASH to begin page2
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sta GBASH
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inner_loop:
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lda even_lookup,X ; get even color
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sta (GBASL),Y ; store it to memory
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iny
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lda odd_lookup,X ; get odd color
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sta (GBASL),Y ; store it to memory
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iny
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bne inner_loop ; repeat for 256
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inc GBASH ; point to next page
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inx ; wrap lookup at 8
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txa
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and #$7
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tax
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lda #$60 ; see if done
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cmp GBASH
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bne inner_loop
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; lda #100 ; A is $60 here
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jsr WAIT ; pause a bit
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; A is 0 here
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inx ; offset next FRAME
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dec FRAME ; exit after so many frames
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bne outer_loop
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;even_lookup:
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;.byte $D7,$DD,$F5,$D5, $D5,$D5,$D5,$D5
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;odd_lookup:
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;.byte $AA,$AA,$AA,$AB, $AB,$AE,$BA,$EA
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