print("This is the program for Car Revers Sensor SYSTEM")
print("BY ANNISHA FOR IOT")

# STEP 1 : IMPORT MODULES OR LIBRARY
from machine import Pin 
from machine import SoftI2C , PWM , Pin
from time import sleep
import ssd1306
import hcsr04


#STEP 2: DECLARE CONNECTION

# ESP32 Pin assignment 

TRIG = Pin(17, Pin.IN)
ECHO = Pin(16, Pin.OUT)


buzzer = PWM(Pin(14), Pin.OUT)


#STEP 2.1 : DECLARE ULTRASONIC
ultrasonicSensor = hcsr04.HCSR04(trigger_pin=17, echo_pin=16,echo_timeout)

#STEP 2.2 : DECLARE THE CONNECTION FOR ULTRASONIC SENSOR
oled_display=SoftI2C (scl=Pin(22), sda = Pin (21)) # to declare pin
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, oled_display)

#STEP 3 : THE PROCESS

while True:
    #FOR ULTRASONIC SENSOR ON THE TERMINAL PART 
    distance_in_cm = ultrasonicSensor.distance_cm()
    distance_in_mm = ultrasonicSensor.distance_mm()

    print('An object is detected in : ' , distance_in_cm , 'cm')
    print('An object is detected in : ' , distance_in_mm , 'mm')
   
 #to display the distance on OLED
    oled.fill(1) # 1 means line number 1
    oled.text('Object detected: ',3,0,0)
    oled.text(str(distance_in_cm),5,20,0)
    oled.text('cm',75,20,0)
    oled.text(str(distance_in_mm),5,40,0)
    oled.text('mm',75,40,0)
    oled.show()

    #BUZZER PART
    if distance_in_cm < 50 :
        for i in range (100)
            buzzer.init(freq=1400,duty=400)
            sleep(0.5)
            buzzer.init(freq=1,duty=0)
            sleep(0.5)

    elif 50 < distance_in_cm < 150 :
         for i in range (100)
            buzzer.init(freq=1400,duty=400)
            sleep(1)
            buzzer.init(freq=1,duty=0)
            sleep(1)
    else:
        buzzer.init(freq=1,duty=0)
    
    sleep(5)