You want to control two LEDs connected to GPIO pins 20 and 21. Which code correctly turns ON pin 20 and turns OFF pin 21 simultaneously using GPIO.output()?

hard📝 Application Q9 of 15

Raspberry Pi - GPIO Basics with Python

You want to control two LEDs connected to GPIO pins 20 and 21. Which code correctly turns ON pin 20 and turns OFF pin 21 simultaneously using GPIO.output()?

AGPIO.output(20, GPIO.HIGH) GPIO.output(21, GPIO.HIGH)

BGPIO.output([20, 21], [GPIO.HIGH, GPIO.LOW])

CGPIO.output(20, 0) GPIO.output(21, 1)

DGPIO.output(20, GPIO.LOW) GPIO.output(21, GPIO.HIGH)

Step-by-Step Solution

Solution:

Step 1: Understand GPIO.output supports list inputs
GPIO.output can take a list of pins and a list of states to set multiple pins at once.
Step 2: Verify correct pin-state pairs
GPIO.output([20, 21], [GPIO.HIGH, GPIO.LOW]) sets pin 20 HIGH and pin 21 LOW simultaneously.
Final Answer:
GPIO.output([20, 21], [GPIO.HIGH, GPIO.LOW]) -> Option B
Quick Check:
GPIO.output accepts lists for multiple pins [OK]

Quick Trick: Use lists in GPIO.output to set multiple pins at once [OK]

Common Mistakes:

Calling GPIO.output separately for each pin
Swapping HIGH and LOW states
Using numeric 1 and 0 instead of GPIO constants

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More Raspberry Pi Quizzes

You want to control two LEDs connected to GPIO pins 20 and 21. Which code correctly turns ON pin 20 and turns OFF pin 21 simultaneously using GPIO.output()?

Step 1: Understand GPIO.output supports list inputs

Step 2: Verify correct pin-state pairs

Final Answer:

Quick Check:

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