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19 lines
330 B
ArmAsm
19 lines
330 B
ArmAsm
;============================
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; flip pages
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;============================
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page_flip:
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flip_pages:
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lda DRAW_PAGE ; 3
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beq was_page1 ; 2/3
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was_page2:
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bit PAGE2 ; 4
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lda #$0 ; 2
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beq done_pageflip ; 2/3
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was_page1:
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bit PAGE1 ; 4
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lda #$4 ; 2
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done_pageflip:
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sta DRAW_PAGE ; 3
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rts
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