#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <ESP32Servo.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for SSD1306 display connected using I2C
#define OLED_RESET     -1 // Reset pin
#define SCREEN_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
const float BETA = 3950;
const int servoPin = 18;
Servo servo;
void setup()
{
  Serial.begin(9600);
  
  // initialize the OLED object
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }
  
  // Clear the buffer.
  display.clearDisplay();

  // Display Text
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(12,26);
  display.println("POWER ON!");
  display.display();
  delay(2000);
  display.clearDisplay();

  // Scroll full screen
  display.setCursor(0,2);
  display.setTextSize(1);
  display.println("     *     ");
  display.println("   ***    *");
  display.println(" ******* **");
  display.println("**********");
  display.println(" ******* **");
  display.println("   ***    *");
  display.println("     *     ");
  display.display();
  display.startscrollright(0x00, 0x07);
  delay(2000);
  display.stopscroll();
  delay(2000);
  display.startscrollleft(0x00, 0x07);
  delay(2000);
  display.stopscroll();
  delay(2000);    
  display.startscrolldiagright(0x00, 0x07);
  delay(2000);
  display.startscrolldiagleft(0x00, 0x07);
  delay(2000);
  display.stopscroll();
  display.clearDisplay();
  analogReadResolution(10);
  pinMode(15,INPUT);
  {
  servo.attach(servoPin, 500, 2400);
  }
  
}

void loop() {
  int pos = 0;
  int analogValue = analogRead(15);
  float k= 1 / (log(1 / (1023. / analogValue - 1)) / BETA + 1.0 / 298.15) - 273.15;
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(16,0);
  display.print("Tank Conditions");
  display.setCursor(6,29);
  display.print("TEMPERATURE = ");
  display.print(k);
  display.print("C");
  display.display();
  for (pos = 0; pos <= 180; pos += 1) {
    servo.write(pos);
    delay(15);
  }
  for (pos = 180; pos >= 0; pos -= 1) {
    servo.write(pos);
    delay(15);
  }
}