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31 lines
685 B
ArmAsm
31 lines
685 B
ArmAsm
; Tiny Pastel
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; draw some scrolling pastel blocks in 16 bytes
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; by Vince `deater` Weaver <vince@deater.net>, --- dSr ---
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; zero page locations
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; ROM calls
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SETCOL = $F864 ; COLOR=A
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PRHEX = $FDE3 ; print hex digit
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COUT = $FDED ; output A to screen
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SETGR = $FB40 ; set lo-res graphics and clear screen
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.zeropage
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tiny_xdraw:
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bit $C050 ; switch to lo-res graphics
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tiny_loop:
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txa
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eor $00,X ; get value from zero page
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jsr SETCOL ; set bottom nibble to top
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jsr COUT ; print to text screen (which is same
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; as lo-res graphics screen) with scroll
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inx
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jmp tiny_loop ; could use bvc to save a byte
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; but we can be sure here and we have
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; a byte to spare
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