STC (Set Carry Flag)
Opcodes
| Opcode | Instruction | Op/En | 64-Bit Mode | Compat/Leg Mode | Description |
|---|---|---|---|---|---|
| F9 | STC | NP | Valid | Valid | Set CF flag. |
Instruction Operand Encoding
| Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
|---|---|---|---|---|
| NP | NA | NA | NA | NA |
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.