from machine import ADC,Pin,PWM 
from time import sleep 
 
ldr=ADC(Pin(14)) 
 
ldr.atten(ADC.ATTN_11DB) # max voltage = 3.3V 
ldr.width(ADC.WIDTH_10BIT) #1024 
 
frequency = 5000 
led = PWM(Pin(2), frequency) 
 
 
while True: 
    x=ldr.read() 
    print('LDR value = ', x) 
    voltage = x *(3.3/1023) 
    print('Voltage is ', voltage) 
    led.duty(x) 
    sleep(0.5)