Question

The register that stores all the interrupt requests in it in order to serve them one by one on a priority basis is

(a) Interrupt Request Register

(b) In-Service Register

(c) Priority resolver

(d) Interrupt Mask Register

This question was addressed to me in an interview for job.

This interesting question is from Programmable Interrupt Controller 8259A topic in section Special Purpose Programmable Peripheral devices and their Interfacing of Microprocessor

Answer 1

Right answer is (a) Interrupt Request Register

The explanation: The interrupts at IRQ input lines are handled by Interrupt Request Register internally.