# Import required libraries
from machine import Pin
import utime

# Define the trigger and echo pins
trigger_pin = Pin(5, Pin.OUT)
echo_pin = Pin(6, Pin.IN)
led_pin = Pin(7, Pin.OUT)

# Define a function to get the distance measured by the sensor
def get_distance():
    # Set the trigger pin to high for 10 microseconds to send a pulse
    trigger_pin.high()
    utime.sleep_us(10)
    trigger_pin.low()
    
    # Wait for the echo pin to go high and measure the time taken
    while echo_pin.value() == 0:
        pulse_start = utime.ticks_us()
    while echo_pin.value() == 1:
        pulse_end = utime.ticks_us()
    
    # Calculate the distance using the time taken for the pulse to return
    pulse_duration = utime.ticks_diff(pulse_end, pulse_start)
    distance_cm = pulse_duration / 58
    
    return distance_cm

# Main program loop
while True:
    # Get the distance and print it
    distance = get_distance()
    print("Distance:", distance, "cm")
    if distance < 200:
        led_pin.on()
    else:
        led_pin.off()
    
    # Wait for some time before taking another measurement
    utime.sleep(1)