from machine import Pin, time_pulse_us
import utime

# Define GPIO pins
TRIG = Pin(3, Pin.OUT)
ECHO = Pin(2, Pin.IN)

def measure_distance():
    TRIG.low()
    utime.sleep_us(2)
    TRIG.high()
    utime.sleep_us(10)
    TRIG.low()
    
    pulse_duration = time_pulse_us(ECHO, 1, 30000)  # Max timeout 30ms
    if pulse_duration < 0:
        return None  # No echo detected
    
    distance_cm = (pulse_duration * 0.0343) / 2  # Convert to cm
    return distance_cm

while True:
    distance = measure_distance()
    if distance is not None:
        print("Distance:", round(distance, 2), "cm")
    else:
        print("Out of range")
    
    utime.sleep(1)  # Wait before next reading