Protection Control Instructions
All instructions on this page require 286 or higher CPU.
LGDT src load Global Descriptor Table from 6-byte table at src
SGDT dest store 6-byte Global Descriptor Table to memory at dest
LIDT src load Interrupt Descriptor Table from 6-byte table at src
SIDT dest store 6-byte Interrupt Descriptor Table to memory at dest
LLDT src load Local Descriptor Table (GDT selector) from reg/mem16
SLDT dest store Local Descriptor Table register into dest (r/m16)
LMSW src load Machine Status Word (use to enter protected mode)
SMSW src store Machine Status Word to reg/mem16
LTR src load Task Register (GDT selector) from reg/mem16
STR dest store Task Register to reg/mem16
LAR dest,src load high-byte of dest with Access Rights of src descriptor
LSL dest,src load dest with Segment Limit of descriptor named by src
ARPL lvl Adjust Requested Privilege Level to higher of current or lvl
VERR seg Sets ZF to ZR if task has read privileges for segment seg
VERW seg Sets ZF to ZR if task has write privileges for segment seg
────────────────────────────────────────────────────────────────────────────
Instruction Set