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4 <TITLE>80386 Programmer's Reference Manual -- Opcode DAA
</TITLE>
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14 <H1>DAA -- Decimal Adjust AL after Addition
</H1>
17 Opcode Instruction Clocks Description
19 27 DAA
4 Decimal adjust AL after addition
25 IF ((AL AND
0FH)
> 9) OR (AF =
1)
32 IF (AL
> 9FH) OR (CF =
1)
42 Execute DAA only after executing an
43 <A HREF=
"ADD.htm">ADD
</A> instruction that leaves a
44 two-BCD-digit byte result in the AL register. The
45 <A HREF=
"ADD.htm">ADD
</A> operands should
46 consist of two packed BCD digits. The DAA instruction adjusts AL to
47 contain the correct two-digit packed decimal result.
49 <H2>Flags Affected
</H2>
51 AF and CF as described above; SF, ZF, PF, and CF as described in
52 <A HREF=
"appc.htm">Appendix C
</A>.
54 <H2>Protected Mode Exceptions
</H2>
58 <H2>Real Address Mode Exceptions
</H2>
62 <H2>Virtual
8086 Mode Exceptions
</H2>
70 <B>up:
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71 Chapter
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80386 Instruction Set
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