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46 lines
731 B
ArmAsm
46 lines
731 B
ArmAsm
; 16B looks like columns
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; zero page locations
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HGR_SHAPE = $1A
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HGR_SHAPE2 = $1B
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GBASL = $26
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GBASH = $27
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; ROM calls
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HGR2 = $F3D8
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HGR = $F3E2
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HPOSN = $F411
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XDRAW0 = $F65D
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XDRAW1 = $F661
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tiny_xdraw:
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; loads at E7 (HGR_SCALE) which is $20 (jsr instruction)
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jsr HGR2 ; Hi-res, full screen ; 3
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; Y=0, A=0 after this call
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; we really have to call this, otherwise it won't run
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; on some real hardware
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jsr HPOSN ; set screen position to X= (y,x) Y=(a)
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; saves X,Y,A to zero page
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; after Y= orig X/7
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; A and X are ??
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tiny_loop:
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ldy #$e3
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inx ; X is 1
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lda #2 ; ROT=2
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jsr XDRAW0 ; XDRAW 1 AT X,Y
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; Both A and X are 0 at exit
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; Z flag set on exit
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; Y varies
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beq tiny_loop ; bra
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