// Date and time functions using a DS1307 RTC connected via I2C and Wire lib
#include <Wire.h>
#include "RTClib.h"

#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128    // OLED display width, in pixels
#define SCREEN_HEIGHT 64    // OLED display height, in pixels

// Declaration dor an SSD1309 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
 
RTC_DS1307 rtc;
 
void setup () {

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3D)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
 
  while (!Serial); // for Leonardo/Micro/Zero
 
  Serial.begin(57600);
  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }
 
  if (! rtc.isrunning()) {
    Serial.println("RTC is NOT running!");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    Serial.println("RTC adjusted!");
  }
}
 
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(now.hour(), DEC);
    Serial.print(':');
    Serial.print(now.minute(), DEC);
    Serial.print(':');
    Serial.print(now.second(), DEC);
    Serial.println();

    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(10, 30);
    display.print(now.year(), DEC);
    display.print('/');
    display.print(now.month(), DEC);
    display.print('/');
    display.println(now.day(), DEC);

    display.setCursor(10, 50);
    display.print(now.hour(), DEC);
    display.print(':');
    display.print(now.minute(), DEC);
    display.print(':');
    display.print(now.second(), DEC);
    display.println();

    display.display();
 
    delay(990);
}