STC

Set Carry Flag

OpcodeInstructionOp/En64-Bit ModeCompat/Leg ModeDescription
F9STCZOValidValidSet CF flag.

Instruction Operand Encoding

Op/EnOperand 1Operand 2Operand 3Operand 4
ZON/AN/AN/AN/A

Description

Sets the CF flag in the EFLAGS register. Operation is the same in all modes.

Operation

CF := 1;

Flags Affected

The CF flag is set. The OF, ZF, SF, AF, and PF flags are unaffected.

Exceptions (All Operating Modes)

#​​​UD If the LOCK prefix is used.

This UNOFFICIAL, mechanically-separated, non-verified reference is provided for convenience, but it may be incomplete or broken in various obvious or non-obvious ways. Refer to Intel® 64 and IA-32 Architectures Software Developer’s Manual for anything serious.