NIELIT 2016 DEC Scientist B (CS) - Section B: 39

Question

External Interrupt may not arise because of

• A. illegal or erroneous use of an instruction.
• B. a timing device.
• C. external source.
• D. I/O devices.

Answer 1

 

An external interrupt is a computer system interrupt that happens as a result of outside interference, whether that's from the user, from peripherals, from other hardware devices or through a network.

for example:-I/O device,external source,a timing device etc

These are different than internal interrupts that happen automatically as the machine reads through program instructions

For example divide by 0 etc

Option A illegal or erroneous use of an instruction is internal interrupt not external interrupt.