Voltage Regulator With Faces

#define ANALOG_IN_PIN A0
#include <EEPROM.h>

#include <LiquidCrystal.h>
LiquidCrystal lcd(12,11,5,4,3,2);

int e;

float voltage=0.0;
float R1 = 82000.0;
float R2 = 18000.0;
float deger=0;
float analog_deger=0;



int CLK = 6;
int DT = 7;
int SW = 8;

int smileface = 9;
int sadface = 10;

int set_voltage;
int counter;
int currentStateCLK;
int lastStateCLK;
unsigned long lastButtonPress=0;
int set_butonu;

void setup()
{
  e = EEPROM.read(0);
  
  lcd.clear();
  lcd.begin(16,2);
 
  Serial.begin(9600);
  pinMode(CLK, INPUT);
  pinMode(DT, INPUT);
  pinMode(SW, INPUT_PULLUP);
  pinMode(smileface, OUTPUT);
  pinMode(sadface, OUTPUT);

  lcd.setCursor(0,0);
  lcd.print("Set Value = ");
  lcd.print(e);
  lcd.setCursor(0,1);
  lcd.print("Change / Confirm");
  delay(3000);
  lcd.clear();
  counter = e;


  }

void loop()
{

 
  currentStateCLK = digitalRead(CLK); 
  // CLK pininde oluan hareketlenmede fazla saymm nlemek iin 
  //sadece 1 durum deiikliine tepki verme
  if (currentStateCLK != lastStateCLK  && currentStateCLK == 1)
  {
 
    //DT pinin durumu CLK pininden farklysa ve saat ynnde evriliyorsa saya  artar.
    if (digitalRead(DT) != currentStateCLK) 
    {
      counter ++; 
    } 
    
    else 
    {
      // Saat yn tersinde azalma
      counter --;   
    }
 

    Serial.print("set ");
    Serial.println(counter);
 }
 
  // son CLK durumunu hatrla
  lastStateCLK = currentStateCLK;
 
  // set deerini oku
  int set_butonu = digitalRead(SW);
 
  //Eer sinyal low ise butona baslmtr.
  if (set_butonu == LOW) 
  {
  
    //eer son low pulse'dan sonra 50 ms gemise 
    //butona baslp braklm ve tekrar baslm demektir
    if (millis() - lastButtonPress > 50) 
    {
      set_voltage = counter;
      
      EEPROM.write(0,set_voltage);
      
      Serial.println("set_voltage=");
      Serial.println(set_voltage);

    }
    
    // son basmay hatrla
    lastButtonPress = millis();
  }

   e = EEPROM.read(0);
   
   delay(1);
  
  analog_deger = analogRead(A0);
  deger = (analog_deger*5.0)/1024.0;
  voltage = deger/(R2/(R1+R2));
  if (voltage<=(e+0.5) && voltage>=(e-0.5) ) 
    {
    digitalWrite(smileface, HIGH);
    digitalWrite(sadface, LOW);
    }    
    else if (voltage >=1 && voltage <=(e-0.5))
    {
      digitalWrite(smileface, LOW);
      digitalWrite(sadface, HIGH);
    }
    else if (voltage >=(e+0.5))
    {
      digitalWrite(smileface, LOW);
      digitalWrite(sadface, HIGH);
    }
    else
    {
    digitalWrite(smileface, LOW);
    digitalWrite(sadface, LOW);
    }
   
 
lcd.setCursor(0,0);
lcd.print("set=");
lcd.print(e);
lcd.setCursor(8,0);
lcd.print("cnt=");
lcd.print(counter);
lcd.setCursor(0,1);
lcd.print("voltage = ");
lcd.print(voltage);





}