What Is An Interrupt Request (IRQ)?

What is an Interrupt Request (IRQ)?

What is an Interrupt Request (IRQ)?

Interrupt Request (IRQ) is a term widely used in the world of computer hardware and software. If you’re new to the tech jargon, you might find this term puzzling. But fear not, we’re here to decode it for you!

Simply put, an Interrupt Request (IRQ) is a signal sent by a device to an operating system, indicating that it requires immediate attention. When a device wants to communicate with the CPU (Central Processing Unit), it uses an Interrupt Request to interrupt the normal execution of the program currently running. Think of it as a way for devices to tap the CPU on the shoulder, saying, “Hey, I need your attention right now!”

When an IRQ is triggered, it allows a high-priority device or an event to pause or override the current operations, ensuring that critical tasks get the necessary processing power from the CPU without unnecessary delays. IRQs are essential for coordinating and managing multiple hardware devices within a computer.

Key Takeaways:

  • Interrupt Request (IRQ) is a signal sent by a device to an operating system, indicating an immediate need for attention.
  • IRQs allow high-priority devices or events to pause or override normal program execution, ensuring critical tasks are processed promptly.

How are Interrupt Requests (IRQs) Managed?

In modern computer systems, the management of IRQs is handled by the operating system’s interrupt controller. The interrupt controller acts as a traffic cop, receiving the IRQ requests from various devices and determining the priority and order in which they should be processed.

Each device is assigned a specific IRQ line, which is a dedicated connection to the interrupt controller. When a device triggers an IRQ, it sends a signal through this line to the interrupt controller, which then forwards the request to the CPU.

Common Uses of Interrupt Requests (IRQs)

IRQs are commonly used in various hardware devices, including:

  • Keyboards and mice: When a key is pressed or a mouse button is clicked, an IRQ is sent to ensure the input is promptly registered by the CPU.
  • Network cards: IRQs are used to process network packets in real-time, ensuring smooth data transfer.
  • Sound cards: When audio data needs to be played or recorded, an IRQ is triggered for uninterrupted sound processing.
  • Hard drives: Disk controllers rely on IRQs to handle read and write operations efficiently.


Interrupt Request (IRQ) is a fundamental concept in computer systems that enables efficient communication between hardware devices and the CPU. By prioritizing high-priority tasks and events, IRQs ensure that critical operations are promptly addressed, contributing to a smooth and responsive computing experience.