from machine import PWM,Pin
from time import sleep
from hcsr04 import HCSR04

ultrasonic = HCSR04(trigger_pin=13, echo_pin=12, echo_timeout_us=1000000)
i=0
buzzer = PWM(Pin(4, Pin.OUT))

while True:
  i+=1
  sleep(2)
  distance = ultrasonic.distance_cm()
  print('Distance:', distance, 'cm')
  if distance >=60 and distance <=80 :
    print(distance)
    buzzer.freq(392)
    sleep(1)
  else:
    buzzer.freq(1)
    sleep(1)