ATmega328 Development Board- 7 Segment

const int sel1=10, sel2=11, sel3=12, sel4=13; //initializing selection pins -Port P3
const int a=2 ,b=3, c=4, d=5, e=6, f=7, g=8, dp=9; //initializing data pins -Port P2
void setup()
{
pinMode(sel1,OUTPUT); //declaring Selection Pins as output
pinMode(sel2,OUTPUT);
pinMode(sel3,OUTPUT);
pinMode(sel4,OUTPUT);
digitalWrite(sel1,LOW); //selecting all 4 digits of 7-Segment display by making it LOW
digitalWrite(sel2,LOW);
digitalWrite(sel3,LOW);
digitalWrite(sel4,LOW);
pinMode(a,OUTPUT); //declaring data pins as output
pinMode(b,OUTPUT);
pinMode(c,OUTPUT);
pinMode(d,OUTPUT);
pinMode(e,OUTPUT);
pinMode(f,OUTPUT);
pinMode(g,OUTPUT);
pinMode(dp,OUTPUT);
delay(100);
}
void loop()
{
// print 0
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,LOW);
digitalWrite(f,LOW);
digitalWrite(g,HIGH);
digitalWrite(dp,LOW);
delay(2000);
// print 1
digitalWrite(a,HIGH);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,HIGH);
digitalWrite(e,HIGH);
digitalWrite(f,HIGH);
digitalWrite(g,HIGH);
digitalWrite(dp,HIGH);
delay(2000);

// print 2
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,HIGH);
digitalWrite(d,LOW);
digitalWrite(e,LOW);
digitalWrite(f,HIGH);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);

// print 3
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,HIGH);
digitalWrite(f,HIGH);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);

// print 4
digitalWrite(a,HIGH);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,HIGH);
digitalWrite(e,HIGH);
digitalWrite(f,LOW);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);
// print 5
digitalWrite(a,LOW);
digitalWrite(b,HIGH);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,HIGH);
digitalWrite(f,LOW);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);
// print 6
digitalWrite(a,LOW);
digitalWrite(b,HIGH);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,LOW);
digitalWrite(f,LOW);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);
// print 7
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,HIGH);
digitalWrite(e,HIGH);
digitalWrite(f,HIGH);
digitalWrite(g,HIGH);
digitalWrite(dp,HIGH);
delay(2000);

// print 8
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,LOW);
digitalWrite(f,LOW);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);
// print 9
digitalWrite(a,LOW);
digitalWrite(b,LOW);
digitalWrite(c,LOW);
digitalWrite(d,LOW);
digitalWrite(e,HIGH);
digitalWrite(f,LOW);
digitalWrite(g,LOW);
digitalWrite(dp,LOW);
delay(2000);
}