Particle: DS3231 Clock Module

/* 
Ks0035 keyestudio DS3231 Clock Module
_________________________________
|  SETUP                          | 
|Sensor pin  ::    Particle pin   |
|   +        ::        3.3v       |
|   -        ::        GND        |
|   SDA      ::        D0         |
|   SCL      ::        D1         |
|_________________________________|
SPECIFICATIONS:
I2C clock module
accurate time module
requires RTC Library
src: https://wiki.keyestudio.com/Ks0039_keyestudio_DS3231_Clock_Module
    https://github.com/rickkas7/Adafruit_RTClib_RK/tree/master/examples

GITHUB REPOSITORY:
https://github.com/apanin/ParticleKeyeStudio37sensorKitExamples
*/


// This #include statement was automatically added by the Particle IDE.
#include <RTClibrary.h>

// Date and time functions using a DS3231 RTC connected via I2C and Wire lib
#include <Wire.h>
// #include "RTClib.h"

RTC_DS3231 rtc;

char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

void setup () {

#ifndef ESP8266
  while (!Serial); // for Leonardo/Micro/Zero
#endif

  Serial.begin(9600);

  delay(3000); // wait for console opening

  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  if (rtc.lostPower()) {
    Serial.println("RTC lost power, lets set the time!");
    // following line sets the RTC to the date & time this sketch was compiled
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    // This line sets the RTC with an explicit date & time, for example to set
    // January 21, 2014 at 3am you would call:
    // rtc.adjust(DateTime(2014, 1, 21, 3, 0, 0));
  }
}

void loop () {
    DateTime now = rtc.now();
    
    Serial.print(now.year(), DEC);
    Serial.print('/');
    Serial.print(now.month(), DEC);
    Serial.print('/');
    Serial.print(now.day(), DEC);
    Serial.print(" (");
    Serial.print(daysOfTheWeek[now.dayOfTheWeek()]);
    Serial.print(") ");
    Serial.print(now.hour(), DEC);
    Serial.print(':');
    Serial.print(now.minute(), DEC);
    Serial.print(':');
    Serial.print(now.second(), DEC);
    Serial.println();
    delay(3000);