Interrupt

• Interrupts

Defn: an event external to the currently executing process that causes a change in the normal flow of instruction execution; usually generated by hardware devices external to the CPU
Typically indicate that some device needs service
http://www.cs.toronto.edu/~demke/469F.06/Lectures/Lecture6.pdf

• Interrupts

An interrupt is an exception, a change of the normal progression, or interruption
in the normal flow of program execution.
An interrupt is essentially a hardware generated function call.
Interrupts are caused by both internal and external sources.
An interrupt causes the normal program execution to halt and for the interrupt
service routine (ISR) to be executed.
At the conclusion of the ISR, normal program execution is resumed at the point
where it was last.
http://web.engr.oregonstate.edu/~traylor/ece473/lectures/interrupts.pdf