void setup() {
  // Setup code
  volatile char *dir;
  dir=0x21;
  *dir=0xFF;
  volatile char *ddir;
  ddir=0x107;
  *ddir=0xFF;
  volatile char *dudir;
  dudir=0x30;
  *dudir=0x00; // Setting it to be an input pin
  //ADCSRA |=(1<<ADEN);// Enable ADC
  //ADMUX=(1<<REFS0);//Here Vref is 5v
 // ADMUX=(1<<REFS1);  //(Here Vref is 1.1v:Interrnal Voltage) Setting reference voltage to AVcc for comparison and to establich a limit
}
void loop() {
  unsigned char digits[]={
    0x3F, // 0
    0x06, // 1
    0x5B, // 2
    0x4F, // 3
    0x66, // 4
    0x6D, // 5
    0x7D, // 6
    0x07, // 7
    0x7F, // 8
    0x6F  // 9
  };
  ADCSRB|=(1<<ACME);
  ADMUX = 1; //selecting A1 pin
  ADCSRA |=(1<<ADSC);// Start ADC conversion
  while(ADCSRA&(1<<ADSC)); //conversion to complete and after that reset
  unsigned int analogValue=ADC;
  unsigned int mappedValue=map(analogValue,0,1023,0,9);//10 bit ADC
  volatile char *outo;
  outo=0x31;
  *outo=mappedValue;
  volatile char *buto;
  buto=0x20;
  *buto=0x10;
  volatile char *out;
  out=0x108;
  *out = digits[*outo];
}