Arduino - Timer (7 segment)

#include "Timer.h"
Timer t;

void setup() {

  for(int i=2;i<14;i++){
    pinMode(i,OUTPUT);
  }
  t.every(1,upali);
  t.every(500,broji);

  digitalWrite(2,HIGH);
  digitalWrite(3,HIGH);
  digitalWrite(4,HIGH);
  digitalWrite(5,HIGH);
}

byte znamenka [4];

void loop() {
  t.update();
}

int br;
void broji(){
  int temp = br;
  for(int i=0; i<4; i++){
    znamenka[i] = (temp)%10;
    temp = temp/10;
  }
  br++;
}

int d=0;
void upali(){
  digitalWrite(d+2,HIGH);
  d--;
  if(d<0){
    d=3;
  }
  switch(znamenka[3 - d]){
    case 0: ispis (0b11000000); break;
    case 1: ispis (0b11111001); break;
    case 2: ispis (0b10100100); break;
    case 3: ispis (0b10110000); break;
    case 4: ispis (0b10011001); break;
    case 5: ispis (0b10010010); break;
    case 6: ispis (0b10000010); break;
    case 7: ispis (0b11111000); break;
    case 8: ispis (0b10000000); break;
    case 9: ispis (0b10010000); break;
    default: break;
  }
  digitalWrite(d+2,LOW);
}

void ispis(byte x){
  for(int i=0; i<8; i++){
    digitalWrite(i+6, x&(1<<i)  );
  }
}