Programmable interrupt controller

<p>In <a href="/facts/Computing/Kghtm9fX">computing</a>, a programmable interrupt controller (PIC) is an <a href="/facts/Integrated_circuit/fjn6vg7C">integrated circuit</a> that helps a <a href="/facts/Microprocessor/Fx9CaQht">microprocessor</a> (or <a href="/facts/CPU/Jxp1bqMV">CPU</a>) handle <a href="/facts/Interrupt_request_(PC_architecture)/n2VvmL4K">interrupt requests</a> (IRQs) coming from multiple different sources (like external I/O devices) which may occur simultaneously. It helps prioritize IRQs so that the CPU switches execution to the most appropriate <a href="/facts/Interrupt_handler/r9ptAjy7">interrupt handler</a> (ISR) after the PIC assesses the IRQs' relative priorities. Common modes of interrupt priority include hard priorities, rotating priorities, and cascading priorities.  PICs often allow mapping input to outputs in a configurable way. On the <a href="/facts/PC_architecture/zGUpl7Sh">PC architecture</a> PIC are typically embedded into a <a href="/facts/Southbridge_(computing)/K0bg0LSP">southbridge chip</a> whose internal architecture is defined by the chipset vendor's standards.
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Programmable interrupt controller open-in-new

Programmable interrupt controller