from hcsr04 import HCSR04
from machine import Pin, PWM
from time import sleep


ultrasonic = HCSR04(trigger_pin=13, echo_pin=12)
buzzer = PWM(Pin(16))

while True:
    # Mengukur jarak
    jarak = ultrasonic.distance_cm()
    print('Jarak', jarak, 'CM')
    sleep(0.1)

    if jarak < 125:
        frequency = int(500 + (125 - jarak) * 5)  
        buzzer.freq(frequency)
        buzzer.duty(512)
        buzzer.duty(0)