14 lines
371 B
ArmAsm
14 lines
371 B
ArmAsm
;; #LAYOUT# STD * #TAKE
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;; #LAYOUT# * BASIC_0 #TAKE
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;; #LAYOUT# * * #IGNORE
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;
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; Math package - helper function to sign extend accumulator into Y
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sign_extend_A_to_Y:
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cmp #$80 ; Copy sign into carry
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ldy #$00 ; Y = $00
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bcc @1 ; Branch if not negative
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dey ; Y = $FF
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@1: rts
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