import time
from machine import Pin,PWM
import random
buzzer = PWM(Pin(1));
# while True:
#     buzzer.freq(random.randint(100,1000));
#     buzzer.duty_u16(512);
#     time.sleep(0.1)
#     buzzer.duty_u16(0);
#     time.sleep(0.1)


trig = Pin(17,Pin.OUT)
echo = Pin(16,Pin.IN)

def dis():
    trig.low()
    time.sleep_us(2000)
    trig.high()
    time.sleep_us(5)
    trig.low()
    start_time = 0
    end_time = 0
    while echo.value() == 0 :
        start_time = time.ticks_us()

    while echo.value() == 1 :
        end_time = time.ticks_us()

    pulse_dur = end_time - start_time
    dist = ( pulse_dur * 0.0343 ) /2
    return round(dist, 2)

while True:
    di = dis()
    print(f"Distance = {di} CM")
    time.sleep(1)