[Solved] What is wrong with this PWM code? import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setup(19, GPIO.OUT) pwm = GPIO.PWM(19, 500) pwm.ChangeDutyCycle(50) | Raspberry Pi

Raspberry Pi - PWM Output

What is wrong with this PWM code?

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(19, GPIO.OUT)
pwm = GPIO.PWM(19, 500)
pwm.ChangeDutyCycle(50)

APin 19 is not set as output

BChangeDutyCycle argument must be a string

CFrequency 500 is invalid

DPWM was not started before changing duty cycle

Step-by-Step Solution

Solution:

Step 1: Check PWM start method usage
Before calling ChangeDutyCycle, PWM must be started with pwm.start(duty_cycle).
Step 2: Validate other parts
Pin 19 is output; frequency 500 is valid; ChangeDutyCycle takes number, not string.
Final Answer:
PWM was not started before changing duty cycle -> Option D
Quick Check:
Call pwm.start() before ChangeDutyCycle [OK]

Quick Trick: Always start PWM before changing duty cycle [OK]

Common Mistakes:

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What is wrong with this PWM code?