ChangeDutyCycle

ChangeDutyCycle is a method that belongs to the RPi.GPIO module in Python. It is commonly used to change the duty cycle of a PWM (Pulse Width Modulation) signal on a Raspberry Pi GPIO pin. The duty cycle represents the percentage of time the signal is in a high state compared to the total period of the signal.

By changing the duty cycle, you can control the average power or brightness of devices such as LEDs, motors, or servo motors connected to the GPIO pin.

Here's an example of how to use the ChangeDutyCycle method:

import RPi.GPIO as GPIO
import time

# Set up GPIO pin
GPIO.setmode(GPIO.BCM)
GPIO.setup(18, GPIO.OUT)

# Create a PWM object
pwm = GPIO.PWM(18, 100)  # GPIO pin 18, frequency 100Hz

# Start PWM with a duty cycle of 50%
pwm.start(50)

# Change the duty cycle to 75% after 2 seconds
time.sleep(2)
pwm.ChangeDutyCycle(75)

# Stop PWM after 5 seconds
time.sleep(5)
pwm.stop()

# Clean up GPIO
GPIO.cleanup()

In this example, we set up GPIO pin 18 as an output and create a PWM object with a frequency of 100Hz. We then start the PWM with a duty cycle of 50% and change it to 75% after 2 seconds. Finally, we stop the PWM after 5 seconds and clean up the GPIO.

Please note that this example assumes you have the RPi.GPIO library installed and are running it on a Raspberry Pi.