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CLD.htm
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<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML>
<HEAD>
<TITLE>80386 Programmer's Reference Manual -- Opcode CLD</TITLE>
</HEAD>
<BODY STYLE="width:80ch">
<B>up:</B> <A HREF="c17.htm">
Chapter 17 -- 80386 Instruction Set</A><BR>
<B>prev:</B><A HREF="CLC.htm"> CLC Clear Carry Flag</A><BR>
<B>next:</B><A HREF="CLI.htm"> CLI Clear Interrupt Flag</A>
<P>
<HR>
<P>
<H1>CLD -- Clear Direction Flag</H1>
<PRE>
Opcode Instruction Clocks Description
FC CLD 2 Clear direction flag; SI and DI
will increment during string
instructions
</PRE>
<H2>Operation</H2>
<PRE>
DF := 0;
</PRE>
<H2>Description</H2>
CLD clears the direction flag. No other flags or registers are affected.
After CLD is executed, string operations will increment the index registers
(SI and/or DI) that they use.
<H2>Flags Affected</H2>
DF := 0
<H2>Protected Mode Exceptions</H2>
None
<H2>Real Address Mode Exceptions</H2>
None
<H2>Virtual 8086 Mode Exceptions</H2>
None
<P>
<HR>
<P>
<B>up:</B> <A HREF="c17.htm">
Chapter 17 -- 80386 Instruction Set</A><BR>
<B>prev:</B><A HREF="CLC.htm"> CLC Clear Carry Flag</A><BR>
<B>next:</B><A HREF="CLI.htm"> CLI Clear Interrupt Flag</A>
</BODY>