/*
- Arduino & Chralieplexing
- Driving 9 LEDs using only 4 I/O Pins
- Tri-State Logic Implementation
- Code written by Ganesh Ram
- Modified from code by T.K.Hareendran
- Tested at Department of Design

*/

#define LED_1 4
#define LED_2 5
#define LED_3 6
#define LED_4 7
#define buttonApin 11
#define buttonBpin 12
int i=0;
char input;
void setup()
{
   pinMode(LED_1, INPUT);
   pinMode(LED_2, INPUT);
   pinMode(LED_3, INPUT);
   pinMode(LED_4, INPUT);
   pinMode(buttonApin, INPUT_PULLUP);
   pinMode(buttonBpin, INPUT_PULLUP);
   Serial.begin(9600);
}

void loop()
{

   if (digitalRead(buttonApin) == LOW)
{
   {
    for(i=0;i<=50;i++)
    I();

    for(i=0;i<50;i++)
    alloff();
      
    for(i=0;i<=50;i++)
    I();

    for(i=0;i<50;i++)
    alloff();

    for(i=0;i<=50;i++)
    T();

    for(i=0;i<50;i++)
    alloff();

    for(i=0;i<=50;i++)
    D();

    for(i=0;i<50;i++)
    alloff();
    
   
  }


}

   if (digitalRead(buttonBpin) == LOW)
  {
    for(int n= 0; n<5; n++)
    {
      for(i=0;i<50;i++)
      allon();

      for(i=0;i<50;i++)
      alloff();

    }
  }

   
   if (Serial.available()) {
    input = Serial.read();//read the input
    if (input == 'a' || input == 'A') 
    {
      for(i=0;i<=50;i++)
       {
          A();
       }
    }

    if (input == 'b' || input == 'B') 
    {
      for(i=0;i<=50;i++)
       {
          B();
       }
    }

    if (input == 'c' || input == 'C') 
    {
      for(i=0;i<=50;i++)
       {
          C();
       }
    }

     if (input == 'd' || input == 'D') 
    {
      for(i=0;i<=50;i++)
       {
          D();
       }
    }

     if (input == 'e' || input == 'E') 
    {
      for(i=0;i<=50;i++)
       {
          E();
       }
    }

     if (input == 'f' || input == 'F') 
    {
      for(i=0;i<=50;i++)
       {
          F1();
       }
    }

     if (input == 'g' || input == 'G') 
    {
      for(i=0;i<=50;i++)
       {
          G();
       }
    }

     if (input == 'h' || input == 'H') 
    {
      for(i=0;i<=50;i++)
       {
          H();
       }
    }

     if (input == 'i' || input == 'I') 
    {
      for(i=0;i<=50;i++)
       {
          I();
       }
    }

     if (input == 'j' || input == 'J') 
    {
      for(i=0;i<=50;i++)
       {
          J();
       }
    }

     if (input == 'k' || input == 'K') 
    {
      for(i=0;i<=50;i++)
       {
          K();
       }
    }

     if (input == 'l' || input == 'L') 
    {
      for(i=0;i<=50;i++)
       {
          L();
       }
    }

     if (input == 'm' || input == 'M') 
    {
      for(i=0;i<=50;i++)
       {
          M();
       }
    }

     if (input == 'n' || input == 'N') 
    {
      for(i=0;i<=50;i++)
       {
          N();
       }
    }

     if (input == 'o' || input == 'O') 
    {
      for(i=0;i<=50;i++)
       {
          O();
       }
    }

     if (input == 'p' || input == 'P') 
    {
      for(i=0;i<=50;i++)
       {
          P();
       }
    }

     if (input == 'q' || input == 'Q') 
    {
      for(i=0;i<=50;i++)
       {
          Q();
       }
    }

     if (input == 'r' || input == 'R') 
    {
      for(i=0;i<=50;i++)
       {
          R();
       }
    }

     if (input == 's' || input == 'S') 
    {
      for(i=0;i<=50;i++)
       {
          S();
       }
    }

     if (input == 't' || input == 'T') 
    {
      for(i=0;i<=50;i++)
       {
          T();
       }
    }

     if (input == 'u' || input == 'U') 
    {
      for(i=0;i<=50;i++)
       {
          U();
       }
    }
     if (input == 'v' || input == 'V') 
    {
      for(i=0;i<=50;i++)
       {
          V();
       }
    }

     if (input == 'w' || input == 'W') 
    {
      for(i=0;i<=50;i++)
       {
          W();
       }
    }

     if (input == 'x' || input == 'X') 
    {
      for(i=0;i<=50;i++)
       {
          X();
       }
    }

     if (input == 'y' || input == 'Y') 
    {
      for(i=0;i<=50;i++)
       {
          Y();
       }
    }

     if (input == 'z' || input == 'Z') 
    {
      for(i=0;i<=50;i++)
       {
          Z();
       }
    }

     Serial.println (input);//print the latter saved in the input var

   } 

/*   set_pins(LED_1, LED_2); //LED 1A
   delay(100);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(100);
  set_pins(LED_1, LED_4);  //LED 1C
   delay(100);
   set_pins(LED_4, LED_1); //LED 2C
   delay(100);
   set_pins(LED_3, LED_2); //LED 2B
   delay(100);
   set_pins(LED_2, LED_3); //LED 2A
   delay(100); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(100);
   set_pins(LED_3, LED_4); //LED 3B
   delay(100);
   set_pins(LED_4, LED_3); //LED 3A
   delay(100); */

   
}

void set_pins(int high_pin, int low_pin)
{
   reset_pins();
   pinMode(high_pin, OUTPUT);
   pinMode(low_pin, OUTPUT);
   digitalWrite(high_pin, HIGH);
   digitalWrite(low_pin,LOW);
}

void reset_pins()
{
   pinMode(LED_1, INPUT); 
   pinMode(LED_2, INPUT);
   pinMode(LED_3, INPUT);
   pinMode(LED_4, INPUT);
   digitalWrite(LED_1, LOW);
   digitalWrite(LED_2, LOW);
   digitalWrite(LED_3, LOW);
   digitalWrite(LED_4, LOW);
}

void A()
{

   

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2);
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //  set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
  // set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
 
}

void B()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
 // set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}


void C()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //  set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void D()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
 // set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //  set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
 //  set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void E()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void F1()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
 //  set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
 //  set_pins(LED_2, LED_4); //LED 3C
   delay(2);
//   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void G()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
 // set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //  set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void H()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
 //  set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
  // set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void I()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
 //  set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void J()
{

   //set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
  // set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
  // set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void K()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
 //  set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void L()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
 //  set_pins(LED_2, LED_1); //LED 1B
   delay(2);
 // set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
 // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //  set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void M()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
  // set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void N()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void O()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
 //set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void P()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
 //  set_pins(LED_2, LED_4); //LED 3C
   delay(2);
 //  set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void Q()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
  // set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
 //  set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
 //  set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void R()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
  // set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
 //  set_pins(LED_2, LED_4); //LED 3C
   delay(2);
  // set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void S()
{

   //set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   //set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   //set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   //set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void T()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   //set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   //set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   //set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   //set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void U()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   //set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   //set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void V()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
  // set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
 //  set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
  // set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void W()
{

 // set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
 //  set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void X()
{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
 //  set_pins(LED_2, LED_1); //LED 1B
   delay(2);
  set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
 //  set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
  // set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
 //  set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void Y()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
  // set_pins(LED_2, LED_1); //LED 1B
   delay(2);
  set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
  // set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
  // set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
 //  set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void Z()
{

  set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
   set_pins(LED_1, LED_4);  //LED 1C
   delay(2); 
  // set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2); 
  // set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2); 
   set_pins(LED_4, LED_3); //LED 3A
   delay(2); 
   
  
}

void allon()

{

   set_pins(LED_1, LED_2); //LED 1A
   delay(2);                
   set_pins(LED_2, LED_1); //LED 1B
   delay(2);
  set_pins(LED_1, LED_4);  //LED 1C
   delay(2);
   set_pins(LED_4, LED_1); //LED 2C
   delay(2);
   set_pins(LED_3, LED_2); //LED 2B
   delay(2);
   set_pins(LED_2, LED_3); //LED 2A
   delay(2); 
   set_pins(LED_2, LED_4); //LED 3C
   delay(2);
   set_pins(LED_3, LED_4); //LED 3B
   delay(2);
   set_pins(LED_4, LED_3); //LED 3A
   delay(2);

}

void alloff()

{
 reset_pins();
 delay(20);
  
}