hw/i386.reference/CLI.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Opcode CLI</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="CLD.htm"> CLD Clear Direction Flag</A><BR>
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  13 <P>
  14 <H1>CLI -- Clear Interrupt Flag</H1>
  15
  16 <PRE>
  17 Opcode    Instruction    Clocks   Description
  18
  19 FA        CLI            3        Clear interrupt flag; interrupts disabled
  20 </PRE>
  21
  22
  23 <H2>Operation</H2>
  24
  25 <PRE>
  26 IF := 0;
  27 </PRE>
  28
  29 <H2>Description</H2>
  30
  31 CLI clears the interrupt flag if the current privilege level is at least as
  32 privileged as IOPL. No other flags are affected. External interrupts are not
  33 recognized at the end of the CLI instruction or from that point on until the
  34 interrupt flag is set.
  35
  36 <H2>Flags Affected</H2>
  37
  38 IF := 0
  39
  40 <H2>Protected Mode Exceptions</H2>
  41
  42 #GP(0) if the current privilege level is greater (has less privilege) than
  43 the IOPL in the flags register. IOPL specifies the least privileged level at
  44 which I/O can be performed.
  45
  46 <H2>Real Address Mode Exceptions</H2>
  47
  48 None
  49
  50 <H2>Virtual 8086 Mode Exceptions</H2>
  51
  52 #GP(0) as for Protected Mode
  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="CLD.htm"> CLD Clear Direction Flag</A><BR>
  61 <B>next:</B><A HREF="CLTS.htm"> CLTS Clear Task-Switched Flag in CR0</A>
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