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36 lines
564 B
NASM
36 lines
564 B
NASM
.outfile "printinput.prg"
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.require "platform/c64header.oph"
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.require "platform/c64kernal.oph"
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.data
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.org $C000
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.space _na 1 ; a的临时存放处
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.text
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main:
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* jsr getin
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beq skip
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cmp #'@
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beq end
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jsr printbyte
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lda #13 ; 换行
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jsr chrout
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skip:
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jmp -
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end:
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rts
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printbyte:
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sta _na
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txa
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pha
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ldx #8 ; 打印8bit
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* lda #$30 ; a = '0'
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asl _na ; 左移一位，溢出到c
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adc #0 ; a = a + c + 0
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jsr chrout ; putchar(a)
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dex ; x--
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bne - ; if(x != 0) goto 上个星号
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pla
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tax
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rts |