from machine import Pin, PWM
import time

ledPin = 33  
pwm = PWM(Pin(ledPin))
pwm.freq(1000)  

brightness = 0
fadeAmount = 20  
interval = 0.01  

while True:
    brightness += fadeAmount

   
    if brightness >= 1023:
        brightness = 1023
        fadeAmount = -fadeAmount
    elif brightness <= 0:
        brightness = 0
        fadeAmount = -fadeAmount

    pwm.duty(brightness)  
    time.sleep(interval)