from machine import Pin
from utime import sleep, sleep_us, ticks_us, ticks_diff

# Inisialisasi pin-pins untuk sensor ultrasonik dan LED
trig = Pin(12, Pin.OUT)
echo = Pin(14, Pin.IN)
red_led = Pin(25, Pin.OUT)
yellow_led = Pin(26, Pin.OUT)
green_led = Pin(27, Pin.OUT)

while True:
    sleep(0.1)

    trig.value(True)
    sleep_us(10)
    trig.value(False)

   
    while echo.value() == False:
        pass

    timer_start = ticks_us()

    while echo.value() == True:
        pass

    timer_end = ticks_us()

    duration = ticks_diff(timer_end, timer_start)
    distance = duration * 0.0343 / 2 

    print("Jarak bumper belakang mobil dengan tembok = ", distance, "cm")

    if distance <= 100:  
        red_led.on()
        yellow_led.off()
        green_led.off()
    elif distance <= 200: 
        red_led.off()
        yellow_led.on()
        green_led.off()
    else:
        red_led.off()
        yellow_led.off()
        green_led.on()