hw/i386.reference/AAM.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Opcode AAM</TITLE>
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   7 <B>up:</B> <A HREF="c17.htm">
   8 Chapter 17 -- 80386 Instruction Set</A><BR>
   9 <B>prev:</B><A HREF="AAD.htm"> AAD ASCII Adjust AX before Division</A><BR>
  10 <B>next:</B><A HREF="AAS.htm"> AAS ASCII Adjust AL after Subtraction</A>
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  13 <P>
  14 <H1>AAM -- ASCII Adjust AX after Multiply</H1>
  15
  16 <PRE>
  17 Opcode    Instruction    Clocks    Description
  18
  19 D4 0A     AAM            17        ASCII adjust AX after multiply
  20 </PRE>
  21
  22 <H2>Operation</H2>
  23
  24 <PRE>
  25 AH := AL / 10;
  26 AL := AL MOD 10;
  27 </PRE>
  28
  29 <H2>Description</H2>
  30
  31 Execute AAM only after executing a
  32 <A HREF="MUL.htm">MUL</A> instruction between two unpacked
  33 BCD digits that leaves the result in the AX register. Because the result is
  34 less than 100, it is contained entirely in the AL register. AAM unpacks the
  35 AL result by dividing AL by 10, leaving the quotient (most-significant
  36 digit) in AH and the remainder (least-significant digit) in AL.
  37
  38 <H2>Flags Affected</H2>
  39
  40 SF, ZF, and PF as described in <A HREF="appc.htm">Appendix C</A>; OF, AF, and CF are undefined
  41
  42 <H2>Protected Mode Exceptions</H2>
  43
  44 None
  45
  46 <H2>Real Address Mode Exceptions</H2>
  47
  48 None
  49
  50 <H2>Virtual 8086 Mode Exceptions</H2>
  51
  52 None
  53
  54
  55 <P>
  56 <HR>
  57 <P>
  58 <B>up:</B> <A HREF="c17.htm">
  59 Chapter 17 -- 80386 Instruction Set</A><BR>
  60 <B>prev:</B><A HREF="AAD.htm"> AAD ASCII Adjust AX before Division</A><BR>
  61 <B>next:</B><A HREF="AAS.htm"> AAS ASCII Adjust AL after Subtraction</A>
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