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

TRIG_PIN = 5
ECHO_PIN = 4
SERVO_PIN = 18

trig = Pin(TRIG_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)
servo = PWM(Pin(SERVO_PIN), freq=50)

#------------------------------------------------------------------
def set_servo_angle(angle):
    min_duty = 26
    max_duty = 123
    duty = int(min_duty + (angle / 180) * (max_duty - min_duty))
    servo.duty(duty)
#------------------------------------------------------------------
def get_distance_cm():
    # Trig ultrasonic Pin
    trig.value(0)
    sleep_us(2)
    trig.value(1)
    sleep_us(10)
    trig.value(0)

    duration = time_pulse_us(echo, 1, 30000)

    if duration < 0:
        return 999

    return (duration * 0.0343) / 2
#------------------------------------------------------------------
set_servo_angle(0)
print("Smart Parking Gate Started")

while True:
    # make your code here
    distance = get_distance_cm()
    print(f"Distance = {distance} cm")
    if distance <= 15:
        set_servo_angle(0)
        print("Gate: Open")
    else:
        set_servo_angle(90)
        print("Gate: Closed")

    sleep(0.2)