from machine import *
from time import *

led= Pin(13, Pin.OUT)
ldr = ADC(Pin(26))
sensor_voltage = 3.3
sensor_voltage = 3.3


led.value(0)

trig = Pin(9, Pin.OUT)
echo = Pin(10, Pin.IN)
led = Pin(13, Pin.OUT)
buzzer = PWM(Pin(18))
buzzer.freq(1000)

while True:
    light = ldr.read_u16()
    V = (light / 65535) * sensor_voltage

    if V > 1.5:       
        led.value(0)
        buzzer.duty_u16(0)
        sleep(0.5)
        continue
else:             
        led.value(0)

    trig.value(0)
    sleep_us(2)
    trig.value(1)
    sleep_us(10)
    trig.value(0)

duration = time_pulse_us(echo, 1)
    distance = (duration * 0.0343) / 2

    if distance > 50: 
        led.value(0)
        buzzer.duty_u16(0)
 
   elif 20 < and distance <= 50:
        led.value(1)
     buzzer.duty_u16(0)
  
   else distance <= 20:
        led.value(1)
        buzzer.duty_u16(1)
    
sleep(0.1)