Question

If any interrupt request given to an input pin cannot be disabled by any means then the input pin is called

(a) maskable interrupt

(b) nonmaskable interrupt

(c) maskable interrupt and nonmaskable interrupt

(d) none of the mentioned

This question was addressed to me in a job interview.

Question is taken from Interrupts and Interrupt Service Routines topic in chapter Special Architectural Features and Related Programming of Microprocessor

Answer 1

Right option is (b) nonmaskable interrupt

The explanation is: A nonmaskable interrupt input pin is one which means that any interrupt request at NMI (nonmaskable interrupt) input cannot be masked or disabled by any means.