Question

The primary purpose of an interrupt in a microprocessor is to

• A. Execute instructions faster
• B. Control memory access
• C. Organize Registers
• D. Handle I/O operations efficiently

Hint:

Think of an interrupt as a doorbell. The CPU doesn't have to keep checking the door (polling). It can do other work until the doorbell rings (interrupt occurs), signaling that someone (an I/O device) needs attention.

Answer 1

The Correct Option is D

An interrupt is a signal sent to the microprocessor from a hardware device or a software program, indicating that an event needs immediate attention.
Without interrupts, the microprocessor would have to use a method called polling, where it constantly checks the status of each I/O device to see if it needs service. This is very inefficient as it wastes a lot of CPU time.
With interrupts, the microprocessor can continue executing its main program. When an I/O device (like a keyboard or a disk drive) is ready to send or receive data, it sends an interrupt signal.
The microprocessor then temporarily suspends its current task, saves its state, and executes a special routine called an Interrupt Service Routine (ISR) to handle the I/O operation. After handling the interrupt, it resumes its original task.
This mechanism allows the CPU to manage I/O operations without wasting time waiting, thus handling them much more efficiently.