mirror of
https://github.com/deater/dos33fsprogs.git
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25 lines
503 B
ArmAsm
25 lines
503 B
ArmAsm
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;==========
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; page_flip
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;==========
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page_flip:
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lda DISP_PAGE ; 3
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beq page_flip_show_1 ; 2nt/3
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page_flip_show_0:
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bit PAGE0 ; 4
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lda #4 ; 2
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sta DRAW_PAGE ; DRAW_PAGE=1 ; 3
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lda #0 ; 2
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sta DISP_PAGE ; DISP_PAGE=0 ; 3
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rts ; 6
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page_flip_show_1:
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bit PAGE1 ; 4
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sta DRAW_PAGE ; DRAW_PAGE=0 ; 3
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lda #1 ; 2
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sta DISP_PAGE ; DISP_PAGE=1 ; 3
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rts ; 6
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;====================
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; DISP_PAGE=0 26
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; DISP_PAGE=1 24
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