/*
  Battery Level Monitor 

Mohammad Ali Rezaee
Islamic Azad University of Qods City
Department of Electronic Science
*/
const int analogPin = A4;
float analogValue;
float input_voltage;

int ledPins[] = { 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };
int pinCount = 10;          

void setup()
{
   Serial.begin(9600);     
   pinMode(2,OUTPUT);
   pinMode(3,OUTPUT);
   pinMode(4,OUTPUT);
   pinMode(5,OUTPUT);
   pinMode(6,OUTPUT);
   pinMode(7,OUTPUT);
   pinMode(8,OUTPUT);
   pinMode(9,OUTPUT);
   pinMode(10,OUTPUT);
   pinMode(11,OUTPUT);
   Serial.println("voltage level ");
}

void LED_function(int stage)
{
    for (int j=2; j<=11; j++)
    {
    digitalWrite(j,LOW);
    }
    for (int i=1, l=2; i<=stage; i++,l++)
    {
    digitalWrite(l,HIGH);    //delay(30);
    }
   
}
void loop()
{
//  Conversion formula for voltage
  analogValue = analogRead (A4);
  Serial.println(analogValue);
  delay (1000); 
  input_voltage = (analogValue * 5.0) / 1024.0;
  
  Serial.print("Voltage= ");
  Serial.print(input_voltage);
  delay(100);

  if (input_voltage < 0.50 && input_voltage >= 0.00 )
    {
    digitalWrite(2, HIGH);
    delay (30);
    digitalWrite(2, LOW);
    delay (30);
    }
  else if (input_voltage < 1.00 && input_voltage >= 0.50)
    {
    LED_function(2);
    }
  else if (input_voltage < 1.50 && input_voltage >= 1.00)
    {
    LED_function(3);
    }
  else if (input_voltage < 2.00 && input_voltage >= 1.50)
    {
    LED_function(4);
    }
  else if (input_voltage < 2.50 && input_voltage >= 2.00)
    {
    LED_function(5);
    }
  else if (input_voltage < 3.00 && input_voltage >= 2.50)
    {
    LED_function(6);
    }
  else if (input_voltage < 3.50 && input_voltage >= 3.00)
    {
    LED_function(7);
    }
  else if (input_voltage < 4.00 && input_voltage >= 3.50)
    {
    LED_function(8);
    }
  else if (input_voltage < 4.50 && input_voltage >= 4.00)
    {
    LED_function(9);
    }
  else if (input_voltage < 5.00 && input_voltage >= 4.50)
    {
    LED_function(10);
    }
}