from machine import Pin, time_pulse_us
import time

# Defining the pin connections for Ultrasonic Sensor and Buzzer
trigger_pin = 27  # initialize the trigger pin to 27 
echo_pin = 26     # initialize the echo pin to 26
buzzer_pin = 17   # initialize the buzzer pin to 17 

# Initializing the pins as Input or Output 
trigger = Pin(trigger_pin, Pin.OUT)
echo = Pin(echo_pin, Pin.IN)
buzzer=Pin(buzzer_pin,Pin.OUT)

# Creating a function to measure distance using Ultrasonic Sensor
def measure_distance():
    # Sending a 10 microsecond pulse to trigger the sensor
    trigger.value(1)
    time.sleep_us(10)
    trigger.value(0)

    # Measuring the duration of the pulse on the echo pin
    duration = time_pulse_us(echo, 1, 30000)  # Timeout set to 30,000 microseconds (30ms)

    # Calculating distance in centimeters
    distance_cm = (duration / 2) /29.1

    return distance_cm #returning the calculated distance

# Main loop
while True:
        distance = measure_distance()
        print("Distance:", distance, "cm")

    # Wait for some time before the next measurement
        time.sleep(1)
        # The conditional statements for the buzzer
        if distance<15:
            buzzer.value(1) # Activates the buzzer
        else:
            buzzer.value(0) # Decactivates the buzzer