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30 lines
559 B
ArmAsm
30 lines
559 B
ArmAsm
" Simple cat program: echo stdin to stdout until no more words to read
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main:
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" Read 5 words into the buffer from stdin
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lac d0
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sys read; buf; 5
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spa " Skip if result was >= 0
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jmp error " Result was -ve, so error result
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sna " Skip if result was >0
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jmp end " Result was zero, so nothing left to read
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" Save the count of words read in
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dac 1f
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" Write 5 words from the buffer to stdout
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lac d1
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sys write; buf; 1:0
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jmp main
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error:
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end:
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" exit
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sys exit
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d0: 0
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d1: 1
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" Input buffer for read
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buf: 0; 0; 0; 0; 0
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