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jeff-1amstudios/alphabet.asm

Last active August 29, 2015 14:10
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c64 initial screen
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alphabet.asm
ldx #0 ; X = 0
.loop
txa ; copy X to A
sta $0400, x ; put A at $0400+X
sta $d800, x ; put A as a color at $d800+x. Color RAM only considers the lower 4 bits,
; so even though A will be > 15, this will wrap nicely around the 16 available colors
inx ; X=X+1
cpx #27 ; have we written enough chars?
bne .loop
rts ; all done
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