Non-Maskable Interrupt

What Does Non-Maskable Interrupt Mean?

A non-maskable interrupt (NMI) is a type of hardware
interrupt (or signal to the processor) that prioritizes a certain thread
or process. Unlike other types of interrupts, the non-maskable interrupt cannot
be ignored through the use of interrupt masking techniques.


Techopedia Explains Non-Maskable Interrupt

Common examples of non-maskable interrupt include types of
internal system chipset errors, memory corruption problems, parity errors and
high-level errors needing immediate attention. In a sense, a non-maskable
interrupt is a way to prioritize certain signals within the operating system.
Another example is the user event non-maskable interrupt, where a user presses
control, alt, delete to create an immediate signal to the system when the
computer is not responding. This is a good example because it illustrates a
kind of “override” – rather than just following the general thread or process,
the ctrl-alt-delete produces a signal that the computer must and will deal with


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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.