// ***************************************
// * Breakout board RTC esterno I2C      *
// * Marca: APKLVSR                      *
// * Modello: DS3231                     *
// * Memoria: AT24C32 32 Gb              *
// * Pin GND: GND                        *
// * Pin VCC: alimentazione DC 3,3 o 5 V *
// * Pin SDA: input analogico            *
// * Pin SCL: input analogico            *
// * Pin SQW: output ad onda quadra      *
// * Pin 32K: output analogico 32 Khz    *
// * LED: PWR (power)                    *
// * Batteria tampone: CR2032            *
// * Indirizzi I2C del modulo:           *
// * 87 (0x57)                           *
// * 104 (0x68)                          *
// ***************************************

#include <Arduino.h>
#include <Wire.h>
#include <SPI.h>
#include "RTClib.h"

RTC_DS3231 objRtc;

//char  *res = malloc(5);
char *res = (char*)malloc(5 * sizeof(char));

String pad(int n)
{
  sprintf(res, "%02d", n);
  return String(res);  
}

void setup()
{
  Serial.begin(9600);
  
  while(!objRtc.begin())
  {
    Serial.println("Controlla le connessioni alla breakout board RTC esterna");
  }

  if (objRtc.lostPower())
  {
    Serial.println("Imposto data/ora");
    objRtc.adjust(DateTime(F(__DATE__), F(__TIME__)));    
    // rtc.adjust(DateTime(2014, 1, 21, 3, 0, 0));
  }
}

void loop()
{
  DateTime now = objRtc.now();
   
  Serial.print(pad(now.day()));
  Serial.print('/');
  Serial.print(pad(now.month()));
  Serial.print('/');
  Serial.print(now.year(), DEC);
  Serial.print(" - ");
  Serial.print(pad(now.hour()));
  Serial.print(':');
  Serial.print(pad(now.minute()));
  Serial.print(':');
  Serial.print(pad(now.second()));
  Serial.println();

  delay(5000);
}