from machine import Pin,ADC,PWM
from time import sleep

adc = ADC(Pin(1))
adc.atten(ADC.ATTN_11DB)
led_pwm = PWM(Pin(19,Pin.OUT),freq=1000)

while True:
    duty_adc = adc.read_u16()
    led_pwm.duty_u16(duty_adc)
    sleep(0.1)