Understanding the Key Differences Between NMI and Normal Interrupts

Aditya Bhuyan
7 min readNov 13, 2024

Introduction

Interrupts are a crucial aspect of modern computing systems. They allow processors to temporarily suspend their current tasks and switch to handling more urgent processes. Interrupts come in various types, with two of the most significant being Normal Interrupts and Non-Maskable Interrupts (NMIs). While they share the same basic purpose — to interrupt the processor and trigger specific actions — they differ significantly in their usage, handling, and priority.

In this article, we’ll explore the differences between normal interrupts and NMIs, why these differences matter, and in which situations you might choose one over the other. By the end of this guide, you’ll have a comprehensive understanding of these two types of interrupts and their role in embedded systems, microprocessors, and computing hardware.

What is an Interrupt?

First things first: let’s get a grasp on what an interrupt is before we go into the specifics of Normal Interrupts and NMIs. An interruption is a signal that is transmitted to the processor of a computing system to indicate that it should halt the execution that it is now performing in order to deal with a particular activity or occurrence. Having this capability is essential for systems that are…

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Aditya Bhuyan
Aditya Bhuyan

Written by Aditya Bhuyan

I am Aditya. I work as a cloud native specialist and consultant. In addition to being an architect and SRE specialist, I work as a cloud engineer and developer.

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