"""
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃ Raspberry Pi Pico HC-SR04 Ultrasonic Sensor (MicroPython)┃
┃                                                          ┃
┃ A program to measure distances using the HC-SR04         ┃
┃ ultrasonic sensor and display the values on an SSD1306   ┃
┃ OLED display or an I2C LCD display connected to a        ┃
┃ Raspberry Pi Pico.                                       ┃
┃                                                          ┃
┃ Copyright (c) 2023 Anderson Costa                        ┃
┃ GitHub: github.com/arcostasi                             ┃
┃ License: MIT                                             ┃
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
"""

from machine import Pin, time_pulse_us
from time import sleep_us, sleep

# Define the GPIO pin numbers for the trigger and echo pins
ECHO_PIN = 26
TRIGGER_PIN = 27

# Initialize trigger and echo pins
trigger = Pin(TRIGGER_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)

def measure_distance():
    # Ensure trigger is low initially
    trigger.low()
    sleep_us(2)

    # Send a 10 microsecond pulse to the trigger pin
    trigger.high()
    sleep_us(10)
    trigger.low()

    # Measure the duration of the echo pulse (in microseconds)
    pulse_duration = time_pulse_us(echo, Pin.high)

    # Calculate the distance (in centimeters) using the speed of sound (343 m/s)
    distance = pulse_duration * 0.0343 / 2
    return distance

def main():
    while True:
        # Measure the distance and print the value in centimeters
        distance = measure_distance()
        print("Distance: {:.2f} cm".format(distance))
        
        # Wait for 1 second before taking the next measurement
        sleep(1)

if __name__ == "__main__":
    main()