the code

// todo timeout and pwm dimming
//Recive varibles

byte Byte = 0;
int nummer = 0;
int Prijs[4] = {0,0,0,0};
int i = 0;
boolean reset = false;
boolean toon = false;
boolean reoutput = true;
boolean easter = true;

// Show variables
int old[4] = {0,0,0,0};
int latch1 = 2;
int latch2 = 3;
int pwmpin = 6;
int value = 255;
int timeout = 0;


// the output




void setup(){

Serial.begin(9600);

pinMode(latch1,OUTPUT);
pinMode(latch2,OUTPUT);

Serial.println ("insert your numbers:");
analogWrite(pwmpin,255);
}

void loop(){
 recive();
 show();

 }



// the main display method

void show()
{

   if( old[0] != Prijs[0])
   {
    old[0] = Prijs[0];
    timeout = 0;
    value = 255;

   }
   if( old[1] != Prijs[1])
   {
    old[1] = Prijs[1];
    timeout = 0;
    value = 255;

   }
    if( old[2] != Prijs[2])
   {
    old[2] = Prijs[2];
    timeout = 0;
    value = 255;

   }
    if( old[3] != Prijs[3])
   {
    old[3] = Prijs[3];
    timeout = 0;
    value = 255;

   } if (timeout = 10){fade();}
}

void fade(){

 if (value > 0){analogWrite (pwmpin,value);
 value = value -10;



 }
}

//the main recive method
 void recive(){ if(Serial.available() ==1){

  Byte = Serial.read ();

 if (Byte == 13){

  switch(reset){

   case false:

     Serial.println(""); Serial.println("het ingegeven nummer is:");
     int a;
     Serial.print(Prijs[0]); Serial.print(Prijs[1]); Serial.print(Prijs[2]); Serial.print(Prijs[3]);
     Serial.println("");

     Serial.println ("Press enter to reset or ? for variables");
     reoutput = false;
     reset = true;
     break;

   case true:
     inputreset();
   break;
   }}

  else { if (reoutput == true){Serial.print(convert1(Byte)); } //convert and show inputted numbers

  Prijs[i] = (convert1(Byte)) ;

        i++;}
}
if ( Byte == 63){ if (toon == false){Serial.println("");
                                     Serial.println("┌-------------------------------------┐");
                                     Serial.print("| old1: ");Serial.print(old[0]);
                                     Serial.print("| old2: ");Serial.print(old[1]);
                                     Serial.print(" | old3: ");Serial.print(old[2]);
                                     Serial.print("| old4: ");Serial.print(old[3]);
                                     Serial.print(" |");
                                     Serial.println("");
                                     Serial.print("| toon: ");Serial.print(toon);
                                     Serial.print("| reset: ");Serial.print(reset);
                                     Serial.print("| reoutput: ");Serial.print(reoutput);
                                     Serial.print("      |");
                                     Serial.println("");
                                     Serial.println("└-------------------------------------┘");
                                     Serial.println(" ");
                                     Serial.println("Press enter to reset");
                                    }
 toon = true;    }

 if( Byte == 33){ if(easter == true){if (Prijs[0]==0 and Prijs[1] == 0 and Prijs[2] == 0 and Prijs[3] ==0){
 Serial.println("");
 Serial.println("              ||||||||||||||||||||||");
 Serial.println("              ||||      ||||| ||||||");
 Serial.println("              |||||||||| |||| ||||||");
 Serial.println("              |||||||||| |||| ||||||");
 Serial.println("              ||||||||| ||||| ||||||");
 Serial.println("              ||||||| ||||||| ||||||");
 Serial.println("              ||||||| ||||||| ||||||");
 Serial.println("              ||||||| ||||||| ||||||");
 Serial.println("              ||||||||||||||||||||||");
 Serial.println("              ||||||||||||||||||||||");
 Serial.println("              ||||||| ||||||| ||||||");
 Serial.println("              ||||||||||||||||||||||");

 }

else {

 Serial.println("              -------------------");
 Serial.print("              |");Serial.print("The Numbers: ");Serial.print(Prijs[0]); Serial.print(Prijs[1]); Serial.print(Prijs[2]); Serial.print(Prijs[3]);Serial.println("|");
 Serial.println("              -------------------");


}
  Serial.println("    ( ( (      o");
 Serial.println("/---\\:::/---\\  o");
 Serial.println("| 0 |   | 0 | o");
 Serial.println("\\---/:::\\---/");
 Serial.println(" | /     \\ |");
 Serial.println(" \\ \\     / /");
 Serial.println("  | \\| |/ |");
 Serial.println("   \\ \\ / /");
 Serial.println("    |---|");
 Serial.println("    |   |");
 Serial.println("   /|\\ /|\\");

 Serial.println("");


 Serial.println("Press enter to reset");







 } easter = false;}



 }


void nixiereset(){

old[0] = 0;
old[1] = 0;
old[2] = 0;
old[3] = 0;

value = 0;
timeout =0;

digitalWrite(latch2,LOW);
digitalWrite(latch1,LOW);

}

void inputreset(){
Byte = 0;
nummer = 0;
Prijs[0] = 0;
Prijs[1] = 0;
Prijs[2] = 0;
Prijs[3] = 0;
i = 0;
reset = 0;
reoutput = true;
toon = false;
easter = true;
Serial.println("gereset");
delay(100);
Serial.println ("insert your numbers:");
}


  int convert1 (int Byte) {

    switch(Byte){

   case 48:
    nummer = 0;
    break;

   case 49:
    nummer = 1;
    break;

   case 50:
    nummer = 2;
    break;

   case 51:
    nummer = 3;
    break;

   case 52:
    nummer = 4;
    break;

   case 53:
    nummer = 5;
    break;

   case 54:
    nummer = 6;
    break;

   case 55:
    nummer = 7;
    break;

   case 56:
    nummer = 8;
    break;

   case 57:
    nummer =9 ;
    break;
   }return nummer;
}

byte convert2 (int nummer) {



  switch(nummer){

   case 0:
    PORTB = B00000000;
    break;

   case 1:
    PORTB = B00000100;   // pin 8
    break;

   case 2:
    PORTB = B00001000; // pin 9
    break;

   case 3:
    PORTB = B00001100; // pin 8 en 9
    break;

   case 4:
    PORTB = B00010000; // pin 10
    break;

   case 5:
    PORTB = B00010100; // pin 8 en 10
    break;

    case 6:
    PORTB = B00011000; // pin 9 en 10

    break;
   case 7:
    PORTB = B00011100; // pin 8,9 en 10
    break;

   case 8:
    PORTB = B00100000; // pin 11
    break;

    case 9:
   PORTB = B00100100; // pin 8 en 11
    break;
   }
}