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Intel 80386 Reference Programmer's Manual

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CLD -- Clear Direction Flag

Opcode    Instruction     Clocks   Description

FC        CLD             2        Clear direction flag; SI and DI
                                   will increment during string
                                   instructions

Operation

DF := 0;

Description

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.

Flags Affected

DF := 0

Protected Mode Exceptions

None

Real Address Mode Exceptions

None

Virtual 8086 Mode Exceptions

None


up: Chapter 17 -- 80386 Instruction Set
prev: CLC Clear Carry Flag
next: CLI Clear Interrupt Flag