from machine import Pin,PWM
import time

def ultra():
    trigger.low()
    time.sleep_us(2)
    trigger.high()
    time.sleep_us(5)
    trigger.low()

    while echo.value() == 0:
        signaloff = time.ticks_us()
    while echo.value() == 1:
        signalon = time.ticks_us()
    
    timepassed = signalon - signaloff
    distance = (timepassed * 0.0343) / 2
    # print("The distance from object is ", distance, "cm")
    return distance

green=Pin(1, Pin.OUT)
green.value(0)
motor = PWM(Pin(27))
motor.freq(50)
close_pos = 500000
open_pos = 1450000
motor.duty_ns(close_pos)

trigger = Pin(20, Pin.OUT)
echo = Pin(19, Pin.IN)

# while True:
#     distance = ultra()
#     if distance < 200 :
#         motor.duty_ns(open_pos)
#         green.on()
#         print('Door Open!')
#     if distance >= 200 :
#         motor.duty_ns(close_pos)
#         green.off()
#         print('Door Closed!')

#     time.sleep(2)
    
state = 'closed'
while True:
    distance = ultra()
    # print(distance)
    if distance < 200 and state=='closed':  # 현상태 유지 시 액션 생략!
        motor.duty_ns(open_pos)
        green.on()
        state = 'open'
        print('Door Open!')
    if distance >= 200 and state=='open':
        motor.duty_ns(close_pos)
        green.off()
        state='closed'
        print('Door Closed!')
        print(distance)

    time.sleep(2)