forked from Apple-2-HW/Apple2-IO-RPi
12 lines
409 B
NASM
12 lines
409 B
NASM
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ldx #$50 ;slot 5 for this test
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start: lda #$80 ;set read flag low (ready to read)
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sta $c08d,x ;bit 1 low for writing values
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waitwl: lda $c08e,x ;bit 0 low for reading values
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bmi waitwl ;wait for write flag low
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jsr $fde3 ;print nibble of data
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lda #$c0 ;set read flag high (done reading)
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sta $c08d,x
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waitwh: lda $c08e,x
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bpl waitwh ;wait for write flag high
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bmi start ;go around againg for next nibble
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