Computer Hardware User's Manual

3-550 Vol. 2A LOCK—Assert LOCK# Signal Prefix
INSTRUCTION SET REFERENCE, A-M
Operation
AssertLOCK#(DurationOfAccompaningInstruction);
Flags Affected
None.
Protected Mode Exceptions
#UD If the LOCK prefix is used with an instruction not listed: ADD,
ADC, AND, BTC, BTR, BTS, CMPXCHG, CMPXCH8B, DEC, INC,
NEG, NOT, OR, SBB, SUB, XOR, XADD, XCHG.
Other exceptions can be generated by the instruction when the
LOCK prefix is applied.
Real-Address Mode Exceptions
Same exceptions as in protected mode.
Virtual-8086 Mode Exceptions
Same exceptions as in protected mode.
Compatibility Mode Exceptions
Same exceptions as in protected mode.
64-Bit Mode Exceptions
Same exceptions as in protected mode.