from machine import Pin, time_pulse_us
import time

# HC-SR04
trig = Pin(15, Pin.OUT)
echo = Pin(14, Pin.IN)

# LED
led = Pin(18, Pin.OUT)

def get_distance():
    # Send trigger pulse
    trig.value(0)
    time.sleep_us(2)

    trig.value(1)
    time.sleep_us(10)

    trig.value(0)

    # Measure echo pulse
    duration = time_pulse_us(echo, 1, 30000)

    # Convert time to distance in cm
    distance = duration / 58

    return distance


while True:
    distance = get_distance()

    print("Distance:", distance, "cm")

    if distance < 10:
        led.on()
    else:
        led.off()

    time.sleep(0.5)