[Solved] Find the mistake in this code that causes the LED not to turn on:import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setup(21, GPIO.OUT) GPIO.output(21, 1) | Raspberry Pi

Raspberry Pi - LED and Button Projects

Find the mistake in this code that causes the LED not to turn on:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(21, GPIO.OUT)
GPIO.output(21, 1)

AMissing GPIO.cleanup() at the end

BUsing integer 1 instead of GPIO.HIGH

CPin 21 is not set as input

DGPIO.setmode should be GPIO.BOARD

Step-by-Step Solution

Solution:

Step 1: Check the output signal value
GPIO.output expects GPIO.HIGH or GPIO.LOW constants, not raw integers.
Step 2: Understand why integer 1 may fail
Using 1 instead of GPIO.HIGH can cause unexpected behavior or no output.
Final Answer:
Using integer 1 instead of GPIO.HIGH -> Option B
Quick Check:
Use GPIO.HIGH/LOW constants, not integers [OK]

Quick Trick: Always use GPIO.HIGH or GPIO.LOW, not 1 or 0 [OK]

Common Mistakes:

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