#define dirk ((volatile unsigned char*)0x107)
#define outk ((volatile unsigned char*)0x108)
#define ink ((volatile unsigned char*)0x106)
#define ddra ((volatile unsigned char*)0x21)
#define ddrb ((volatile unsigned char*)0x24)
#define ledout ((volatile unsigned char*)0x22)
#define select ((volatile unsigned char*)0x25)
#define dirf ((volatile unsigned char*)0x30)
#define outf ((volatile unsigned char*)0x31)
void commonanode(volatile long input);
volatile char keypad(void);

void setup(){
  *dirk=0xf0;*ddra=0xff;*ddrb=0x0f;*dirf=0xff;
  volatile char keyin,datacount=0;
  volatile long input,i;
  while(1)
  {
      keyin=0;
      keyin=keypad();
      if(keyin!=0)
      {
        input=(input*10)+(keyin-'0');
        datacount++;
      }
      commonanode(input);
      
   if(datacount>=4)
    {
      for(i=0;i<10;i++){
        commonanode(input);
      }
      datacount=0;
      input=0;
    }
    /*previous code
    if(datacount>=4)
    {
        commonanode(input);
      for(i=0;i<400000;i++);
      datacount=0;
      input=0;
    }*/
  }
}

volatile char keypad(void)
{
  volatile char pressedkey=0;
  volatile long j,row,col;
  for(row=0;row<4;row++)
  {
    *outk=1<<(row+4);
    col=(*ink&0x0f);
    
    if(col!=0)
    {
      for(j=0;j<20000;j++);
      if((*ink&0x80)==0x80)
      {
        if((*ink&0x08)==0x08)
        {
          pressedkey='1';
        }
        else if((*ink&0x04)==0x04)
        {
          pressedkey='2';
        }
        else if((*ink&0x02)==0x02)
        {
          pressedkey='3';
        }
        /*else if((*ink&0x01)==0x01)
        {
          common_anode('A'-7-'0');//A
        }*/
      }
      else if((*ink&0x40)==0x40)
      {
        if((*ink&0x08)==0x08)
        {
          pressedkey='4';
        }
        else if((*ink&0x04)==0x04)
        {
          pressedkey='5';
        }
        else if((*ink&0x02)==0x02)
        {
          pressedkey='6';
        }
        /*else if((*ink&0x01)==0x01)
        {
          common_anode('B'-7-'0');//B
        }*/
      }
      else if((*ink&0x20)==0x20)
      {
        if((*ink&0x08)==0x08)
        {
          pressedkey='7';
        }
        else if((*ink&0x04)==0x04)
        {
          pressedkey='8';
        }
        else if((*ink&0x02)==0x02)
        {
          pressedkey='9';
        }
        /*else if((*ink&0x01)==0x01)
        {
          common_anode('C'-7-'0');//C
        }*/
      }
      else if((*ink&0x10)==0x10)
      {
        /*if((*ink&0x08)==0x08)
        {
          common_anode('*'-'0');//*
        }*/
        if((*ink&0x04)==0x04)
        {
          pressedkey='0';
        }
        /*else if((*ink&0x02)==0x02)
        {
          common_anode('#'-'0');//#
        }
        /*else if((*ink&0x01)==0x01)
        {
          common_anode('D'-7-'0');//D
        }*/
      }
      while((*ink&0x0f)!=0);
          break;
    }
  }
  return pressedkey;
}

void commonanode(volatile long input)
{
  volatile long i,j;
  volatile char thousand,hundred,one,ten;
  volatile char display[10]={0XC0,0XF9,0XA4,0XB0,0X99,0X92,0X82,0XF8,0X80,0X90};
  
  thousand=input/1000;
  hundred=(input%1000)/100;
  ten=(input%100)/10;
  one=input%10;
  if(thousand!=0)
  {
    *select=0x01;
    *ledout=display[thousand];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<6000;i++);

    *select=0x02;
    *ledout=display[hundred];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<6000;i++);

    *select=0x04;
    *ledout=display[ten];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<6000;i++);

    *select=0x08;
    *ledout=display[one];
    for(i=0;i<4000;i++);//wait till display settles
    *ledout=0xff;
    for(i=0;i<6000;i++);
  }
  else if(hundred!=0)
  {
    *select=0x02;
    *ledout=display[hundred];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<9333;i++);

    *select=0x04;
    *ledout=display[ten];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<9334;i++);

    *select=0x08;
    *ledout=display[one];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<9333;i++);
  }
  else if(ten!=0)
  {
    *select=0x04;
    *ledout=display[ten];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<16000;i++);

    *select=0x08;
    *ledout=display[one];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<16000;i++);
  }
  else{
    *select=0x08;
    *ledout=display[one];
    for(i=0;i<4000;i++);
    *ledout=0xff;
    for(i=0;i<36000;i++);
  }     
  }