LED Cube 7x7x7

//This code represent the easiest animation for LED CUBE

int temp = 50, cont = 0;

//This function loads all the cube
void load_all(void) {
  //layer 1
  digitalWrite(A2, LOW);
  digitalWrite(A1, LOW);
  digitalWrite(A0, LOW);
  delay(1);

  //layer 2
  digitalWrite(A2, HIGH);
  digitalWrite(A1, LOW);
  digitalWrite(A0, LOW);
  delay(1);

  //layer 3
  digitalWrite(A2, LOW);
  digitalWrite(A1, HIGH);
  digitalWrite(A0, LOW);
  delay(1);

  //layer 4
  digitalWrite(A2, HIGH);
  digitalWrite(A1, HIGH);
  digitalWrite(A0, LOW);
  delay(1);

  //layer 5
  digitalWrite(A2, LOW);
  digitalWrite(A1, LOW);
  digitalWrite(A0, HIGH);
  delay(1);

  //layer 6
  digitalWrite(A2, HIGH);
  digitalWrite(A1, LOW);
  digitalWrite(A0, HIGH);
  delay(1);

  //layer 7
  digitalWrite(A2, LOW);
  digitalWrite(A1, HIGH);
  digitalWrite(A0, HIGH);
  delay(1);

  //layer 8
  digitalWrite(A2, HIGH);
  digitalWrite(A1, HIGH);
  digitalWrite(A0, HIGH);
  delay(1);

}

//This function actives each layer one time and you can decide the time that the layer turns on
void scrolling(int t) {
  PORTB = 0x00;
  digitalWrite(7, HIGH);
  delay(t);
  digitalWrite(7, LOW);

  digitalWrite(8, HIGH);
  delay(t);
  digitalWrite(8, LOW);

  digitalWrite(9, HIGH);
  delay(t);
  digitalWrite(9, LOW);

  digitalWrite(10, HIGH);
  delay(t);
  digitalWrite(10, LOW);

  digitalWrite(11, HIGH);
  delay(t);
  digitalWrite(11, LOW);

  digitalWrite(12, HIGH);
  delay(t);
  digitalWrite(12, LOW);

  digitalWrite(13, HIGH);
  delay(t);
  digitalWrite(13, LOW);

}

//This animation turns on one layer per time, and it increases the speed of it, so finally you see all cube switched on
void one(void) {
  PORTD = 0xff;
  load_all();
  while (1) {
    scrolling(temp);

    temp = temp - 2;

    if (temp <= 0) {
      temp = 1;
      cont++;
      if (cont == 1000) {
        cont = 0;
        temp = 100;
      }
    }

  }
}

void setup() {
  DDRD = 0xff;
  DDRB = 0xff;
  DDRC = 0xff;

}

void loop() {
  one();
}