40 lines
600 B
NASM
40 lines
600 B
NASM
INCLUDE equates.inc
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INCLUDE macros.inc
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org RAM
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jmp BEGIN
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szTitle rmb 'A','B',00h
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BEGIN:
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ldx szTitle
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bra DELAY10
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ldab 01h ; move 1 into register b
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stab [PORTB] ; light b0
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ldaa [PORTB] ; move contents of PORTB into register a
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ldab [PORTB] ; move contents of PORTB into register b
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ldy 00h
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ldy SCSR
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staa iy,20h
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waitchar1:
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brclr ix,SCSR,20h,waitchar1 ; wait for RDRF
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; branch to waitchar1 if ix+SCSR bit 5 is clear
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ldab RAM
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cmpa RAM
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; bne prend
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inx
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inx
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inx
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bra THIS
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org THIS
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ldab THIS
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bra END
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org END
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prend:
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ldab END
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rts
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