Digital output (GPIO.output) in Raspberry Pi - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does GPIO.output(pin, state) do in Raspberry Pi programming?

It sets the electrical state of a specific pin on the Raspberry Pi to either HIGH (on) or LOW (off), controlling devices like LEDs or motors.

beginner

What are the two possible states you can set with GPIO.output()?

The two states are GPIO.HIGH (or 1) to turn the pin on, and GPIO.LOW (or 0) to turn the pin off.

beginner

Why do you need to set the pin mode to GPIO.OUT before using GPIO.output()?

Because the pin must be configured as an output pin to send signals out. If it’s not set to output, you can’t control devices connected to it.

beginner

What Python library is commonly used to control GPIO pins on a Raspberry Pi?

The RPi.GPIO library is commonly used to control GPIO pins in Python on a Raspberry Pi.

beginner

How do you clean up GPIO settings after your program finishes?

You call GPIO.cleanup() to reset all GPIO pins to their default state, preventing conflicts in future programs.

What does GPIO.output(18, GPIO.HIGH) do?

A Turns pin 18 on

B Turns pin 18 off

C Sets pin 18 as input

D Cleans up GPIO pins

Setting pin 18 to GPIO.HIGH turns it on, sending voltage out.

Before using GPIO.output(), what must you do?

A Call GPIO.cleanup()

B Set the pin mode to GPIO.OUT

C Set the pin mode to GPIO.IN

D Import time module

Pins must be set as output with GPIO.OUT to send signals.

Which library is used to control GPIO pins in Python on Raspberry Pi?

A numpy

B matplotlib

C RPi.GPIO

D pandas

RPi.GPIO is the standard library for GPIO control on Raspberry Pi.

What does GPIO.LOW mean when used with GPIO.output()?

A Reset all pins

B Turn the pin on

C Set pin as input

D Turn the pin off

GPIO.LOW sets the pin voltage to 0, turning it off.

Why should you call GPIO.cleanup() at the end of your program?

A To reset pins and avoid conflicts

B To turn all pins on

C To speed up the program

D To import GPIO library

Cleaning up resets pins to safe states for future use.

Explain how to turn an LED on and off using GPIO.output() on a Raspberry Pi.

Think about setting the pin as output first, then controlling the voltage.

Describe why it is important to call GPIO.cleanup() after controlling GPIO pins.

Consider what happens if pins stay set after your program ends.