int main()
{
  
  volatile char *dir;
  dir = 0x30;
  *dir = 0xFF;

  dir = 0x107;
  *dir = 0XFF;

  volatile unsigned char *green;
  green = 0x31;

  volatile unsigned char *blue;
  blue = 0x108;

  while(1)
  {

    unsigned char w[8] = {0X82,0x82,0x82,0x92,0xAA,0xC6,0x82,0x00};
    unsigned char e[8] = {0X00,0x00,0x3C,0x42,0x7C,0x42,0x3C,0x00};
    unsigned char l[8] = {0x10,0x10,0x10,0x10,0x10,0x14,0x18,0x00};
    unsigned char c[8] = {0x00,0x00,0x3C,0x42,0x40,0x42,0x3C,0x00};
    unsigned char o[8] = {0x00,0x00,0x3C,0x42,0x42,0x42,0x3C,0x00};
    unsigned char m[8] = {0x00,0x00,0x52,0x6D,0x49,0x49,0x49,0x00};

    unsigned char* string_display[7]= {w,e,l,c,o,m,e};  
    char start = 7;
    char _end = 0;
    char row;
    char row_start;

    for(char t = 0;t<7;t++) //for characters
    {
      start = 7;
      while(start>=0)
      {
        for(volatile long o = 0;o<175;o++) //to make each frame last longer
        {
          row = 0;
          for(char j = start;j<8;j++)
          {
            *blue = ~(0x80 >> (row++));
            *green = string_display[t][j];

            for(volatile long i=0;i<100;i++);

            *green = 0x00;
          }
        }
        start--;
      }

      _end = 7;
      row_start = 1;

      while(_end>=0)
      {
        for(volatile long o = 0;o<175;o++)
        { 
          row = row_start;
          for(char j = 0;j<=_end;j++)
          {
            *blue = ~(0x80>>(row++));
            *green = string_display[t][j];

            for(volatile long i=0;i<100;i++);

            *green = 0x00;
          }
        }
        _end--;
        row_start++;
      }
    }

  }
}