Intel Pentium Instruction Set Reference
HLT - Halt
| Code |
Mnemonic |
Description |
| F4 |
HLT |
Halt |
Description
Stops instruction execution and places the processor in a HALT state. An enabled interrupt, NMI, or a reset will resume execution. If an interrupt (including NMI) is used to resume execution after a HLT instruction, the saved instruction pointer (CS:EIP) points to the instruction following the HLT instruction.
The HLT instruction is a privileged instruction. When the processor is running in protected or virtual-8086 mode, the privilege level of a program or procedure must be 0 to execute the HLT instruction.
| Operands |
Bytes |
Clocks |
|
1 |
4 |
NP |
Flags
| ID |
unaffected |
DF |
unaffected |
| VIP |
unaffected |
IF |
unaffected |
| VIF |
unaffected |
TF |
unaffected |
| AC |
unaffected |
SF |
unaffected |
| VM |
unaffected |
ZF |
unaffected |
| RF |
unaffected |
AF |
unaffected |
| NT |
unaffected |
PF |
unaffected |
| IOPL |
unaffected |
CF |
unaffected |
| OF |
unaffected |