#include <SevenSegmentTM1637.h>
#include <SevenSegmentExtended.h>

SevenSegmentExtended  display(A3,9);
volatile int second;
volatile int fenzhong;

void setup(){
  display.begin();
  second = 0;
  fenzhong = 0;
}

void loop(){
  display.printTime(fenzhong,second,true);
  second = second + 1;
  if (second == 60) {
    fenzhong = fenzhong + 1;
    second = second == 0;

  }
  if (fenzhong == 60) {
    second = second == 0;
    fenzhong = fenzhong == 0;

  }

}