STI
Usage: STI Modifies flags: IF
Sets the Interrupt Flag to 1, which enables recognition of all hardware interrupts. If an interrupt is generated by a hardware device, an End of Interrupt (EOI) must also be issued to enable other hardware interrupts of the same or lower priority.
Set Flags
STC ; F9 [8086]
STD ; FD [8086]
STI ; FB [8086]
These instructions set various flags. STC sets the carry flag; STD sets the direction flag; and STI sets the interrupt flag (thus enabling interrupts).
To clear the carry, direction, or interrupt flags, use the CLC, CLD and CLI instruction. To invert the carry flag, use CMC.
Example:
sti