import machine
import time

TRIG_PIN = 5  
ECHO_PIN = 4  
BUZZER_PIN = 12  
LED_PIN = 14  

trigger = machine.Pin(TRIG_PIN, machine.Pin.OUT)
echo = machine.Pin(ECHO_PIN, machine.Pin.IN)
buzzer = machine.PWM(machine.Pin(BUZZER_PIN))
led = machine.PWM(machine.Pin(LED_PIN))

def measure_distance():
    trigger.value(1)
    time.sleep_us(10)
    trigger.value(0)
    
    while echo.value() == 0:
        pass
    pulse_start = time.ticks_us()
    
    while echo.value() == 1:
        pass
    pulse_end = time.ticks_us()
    
    pulse_duration = pulse_end - pulse_start
    distance = (pulse_duration * 0.0343) / 2
    
    return distance

while True:
    distance = measure_distance()
    print("Distance: {} cm".format(distance))

    if distance < 200:
        buzzer_duty = int((200 - distance) * 1.25)  
        led_duty = int((200 - distance) * 1.25)  

        buzzer.duty(buzzer_duty)
        led.duty(led_duty)
    else:
        buzzer.duty(0)
        led.duty(0)

    time.sleep(1)