[Solved] Find the bug in this PIR sensor code snippet:import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setup(21, GPIO.OUT) if GPIO.input(21): print("Motion detected") | Raspberry Pi

Raspberry Pi - gpiozero Library

Find the bug in this PIR sensor code snippet:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(21, GPIO.OUT)
if GPIO.input(21):
    print("Motion detected")

APin 21 should be set as input, not output

BGPIO.setmode is missing

Cprint statement syntax error

DGPIO.input cannot be used on pin 21

Step-by-Step Solution

Solution:

Step 1: Check pin setup direction
Pin connected to PIR sensor must be input, not output.
Step 2: Identify mismatch in code
Pin 21 is set as output but read as input, causing logic error.
Final Answer:
Pin 21 should be set as input, not output -> Option A
Quick Check:
PIR pin must be input to read sensor data [OK]

Quick Trick: Set PIR pin as input before reading with GPIO.input [OK]

Common Mistakes:

Master "gpiozero Library" in Raspberry Pi

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Find the bug in this PIR sensor code snippet: