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178 lines
2.8 KiB
HTML
178 lines
2.8 KiB
HTML
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>16-bit comparisons</TITLE
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><A
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NAME="AEN537"
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>16-bit comparisons</A
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></H1
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><P
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> Doing comparisons on extended precision values is about the same
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as doing them on 8-bit values, but you have to have the value you
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test in memory, since it won't fit in the accumulator all at once.
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You don't have to store the values back anywhere, either, since
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all you care about is the final state of the flags. For example,
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here's a signed comparison, branching to <TT
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CLASS="LITERAL"
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>label</TT
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>
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if the value in $C100-1 is less than 1000 ($03E8):
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> SEC
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LDA $C100
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SBC #$E8
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LDA $C101 ; We only need the carry bit from that subtract
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SBC #$03
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BMI label</PRE
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></TD
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></TABLE
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><P
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> All the commentary on signed and unsigned compares holds for
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16-bit (or higher) integers just as it does for the 8-bit
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ones.
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</P
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