Polling vs interrupt-driven execution in Embedded C - Quick Revision & Key Differences

Recall & Review

beginner

What is polling in embedded systems?

Polling is a method where the CPU repeatedly checks the status of a device or condition in a loop to see if it needs attention.

beginner

What is interrupt-driven execution?

Interrupt-driven execution lets the CPU respond immediately when a device signals an event, pausing current tasks to handle it.

beginner

Name one advantage of polling.

Polling is simple to implement and easy to understand because the CPU controls when it checks devices.

beginner

Name one advantage of interrupt-driven execution.

Interrupts allow the CPU to do other work and only respond when needed, improving efficiency and responsiveness.

beginner

What is a disadvantage of polling compared to interrupts?

Polling wastes CPU time checking devices even when no event occurs, which can slow down the system.

Which method waits actively by checking device status repeatedly?

A Direct memory access

B Interrupt-driven execution

C Polling

D DMA transfer

Polling involves the CPU repeatedly checking the device status in a loop.

What happens in interrupt-driven execution when a device signals an event?

A CPU pauses current task to handle the event

B CPU ignores the event

C CPU restarts

D CPU enters sleep mode

The CPU stops its current work to respond immediately to the interrupt.

Which method is more efficient for CPU usage?

A Interrupt-driven execution

B Polling

C Both are equally efficient

D Neither is efficient

Interrupts let the CPU do other tasks and only respond when needed, saving CPU time.

Which method is simpler to implement for beginners?

A Interrupt-driven execution

B Polling

C Multithreading

D DMA

Polling is straightforward because it just checks device status in a loop.

What is a common drawback of interrupt-driven execution?

A CPU wastes time checking devices

B CPU cannot respond quickly

C It uses more power than polling

D Complexity in handling multiple interrupts

Interrupts require careful handling to manage multiple events and priorities.

Explain the difference between polling and interrupt-driven execution in embedded systems.

Think about how the CPU waits for events in each method.

List advantages and disadvantages of polling and interrupt-driven execution.

Consider what makes each method easy or hard to use and how they affect CPU work.