A.5.20 CLC, CLD, CLI, CLTS: Clear Flags
CLC ; F8 [8086]
CLD ; FC [8086]
CLI ; FA [8086]
CLTS ; 0F 06 [286,PRIV]
These instructions clear various flags. CLC clears the carry flag; CLD
clears the direction flag; CLI clears the interrupt flag (thus disabling
interrupts); and CLTS clears the task-switched (TS) flag in CR0.
To set the carry, direction, or interrupt flags, use the STC, STD and
STI instructions (section A.5.301). To invert the carry flag, use CMC
(section A.5.22).