#define PORTA_DDR*(volatile uint8_t *)0x21
#define PORTA_DATA*(volatile uint8_t *)0x22

int main(){
  PORTA_DDR=0XFF;
  volatile long i,j;
  while(1){
    PORTA_DATA=0X00;
    for(i=0;i<=9;i++){
      switch(i)
      {
        case 0:
        PORTA_DATA=0X3F;
        for(j=0;j<400000;j++){}
        break;
        case 1:
        PORTA_DATA=0X06;
        for(j=0;j<400000;j++){}
        break;
        case 2:
        PORTA_DATA=0X5B;
        for(j=0;j<400000;j++){}
        break;
        case 3:
        PORTA_DATA=0X4f;
        for(j=0;j<400000;j++){}
        break;
        case 4:
        PORTA_DATA=0X66;
        for(j=0;j<400000;j++){}
        break;
        case 5:
        PORTA_DATA=0X6d;
        for(j=0;j<400000;j++){}
        break;
        case 6:
        PORTA_DATA=0X7d;
        for(j=0;j<400000;j++){}
        break;
        case 7:
        PORTA_DATA=0X07;
        for(j=0;j<400000;j++){}
        break;
        case 8:
        PORTA_DATA=0X7f;
        for(j=0;j<400000;j++){}
        break;
        case 9:
        PORTA_DATA=0X6f;
        for(j=0;j<400000;j++){}
        break;
      }
    }
  }
}