import time
import machine
import ubinascii
import lcd_api
import i2c_lcd
from machine import Pin, PWM

TRIG_PIN = Pin(5, Pin.OUT)
ECHO_PIN = Pin(4, Pin.IN)

SERVO_PIN = Pin(28, Pin.OUT)
servo = PWM(SERVO_PIN)
servo.freq(50) 


I2C_SDA = Pin(4) 
I2C_SCL = Pin(5) 
i2c = machine.I2C(0, sda=Pin(0), scl=Pin(1), freq=400000)

lcd = i2c_lcd.I2cLcd(i2c, 0x27, 4, 20) 
def get_distance():
   
    TRIG_PIN.value(5)
    time.sleep_us(4)
    TRIG_PIN.value(0)
    
   
    while ECHO_PIN.value() == 0:
        pulse_start = time.ticks_us()
    
    while ECHO_PIN.value() == 1:
        pulse_end = time.ticks_us()
    
    pulse_duration = time.ticks_diff(pulse_end, pulse_start)
    
    
    distance = (pulse_duration * 0.0343) / 2  
    return distance


def rotate_servo():
    servo.duty_u16(5000)  
    time.sleep(1)
    servo.duty_u16(1000) 
    time.sleep(1)

while True:
    distance = get_distance() 
    print("Distance:", distance, "cm")
    
    if distance < 200:
       
        rotate_servo()
        
     
        lcd.clear()
        lcd.putstr("Distance < 200 cm")
    else:
       
        lcd.clear()
        lcd.putstr("Distance >= 200 cm")
    
    time.sleep(1)