Interrupt

In <a href="/facts/Digital_computer/SQe1aK05">digital computers</a>, an interrupt (sometimes referred to as a trap) is a request for the <a href="/facts/Central_processing_unit/Jxp1bqMV">processor</a> to interrupt currently executing code (when permitted), so that the event can be processed in a timely manner. If the request is accepted, the processor will suspend its current activities, save its <a href="/facts/State_(computer_science)/4Yu8xXHS">state</a>, and execute a <a href="/facts/Function_(programming)/9vFJrg0A">function</a> called an <a href="/facts/Interrupt_handler/r9ptAjy7">interrupt handler</a> (or an interrupt service routine, ISR) to deal with the event. This interruption is often temporary, allowing the software to resume normal activities after the interrupt handler finishes, although the interrupt could instead indicate a fatal error.
Interrupts are commonly used by hardware devices to indicate electronic or physical state changes that require time-sensitive attention. Interrupts are also commonly used to implement <a href="/facts/Computer_multitasking/Q4acPNMv">computer multitasking</a> and <a href="/facts/System_call/NW44AFJr">system calls</a>, especially in <a href="/facts/Real-time_computing/p9HxgL4L">real-time computing</a>. Systems that use interrupts in these ways are said to be interrupt-driven.

Interrupt open-in-new

Interrupt