Hello,
At the moment I'm using Adafruit's library, available here: GitHub - adafruit/RTClib: A fork of Jeelab's fantastic RTC Arduino library. The source code is the example of DS3231 included in the library:
// 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();
Serial.print(" since midnight 1/1/1970 = ");
Serial.print(now.unixtime());
Serial.print("s = ");
Serial.print(now.unixtime() / 86400L);
Serial.println("d");
// calculate a date which is 7 days and 30 seconds into the future
DateTime future (now + TimeSpan(7,12,30,6));
Serial.print(" now + 7d + 30s: ");
Serial.print(future.year(), DEC);
Serial.print('/');
Serial.print(future.month(), DEC);
Serial.print('/');
Serial.print(future.day(), DEC);
Serial.print(' ');
Serial.print(future.hour(), DEC);
Serial.print(':');
Serial.print(future.minute(), DEC);
Serial.print(':');
Serial.print(future.second(), DEC);
Serial.println();
Serial.println();
delay(3000);
}
The tutorial at Tutorial – Using DS1307 and DS3231 Real-time Clock Modules with Arduino | tronixstuff.com - using the simple Wire library - is producing the same symptoms at the function readDS3231time.
The original source what I was experimenting with is:
#include <SPI.h>
#include <PCD8544_SPI.h>
#include <Wire.h>
#include <RTClib.h>
PCD8544_SPI_FB lcd;
RTC_DS3231 rtc;
int PIRPin = 2;
void setup() {
lcd.begin(false, 0xBF, 0x04, 0x14);
lcd.begin();
pinMode(PIRPin,INPUT);
rtc.begin();
if (rtc.lostPower()) {
rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
}
}
void loop() {
DateTime now = rtc.now();
lcd.clear();
if (digitalRead(PIRPin) == HIGH) {
lcd.gotoXY(0,0);
lcd.print("I can see you!");
} else {
lcd.gotoXY(0,0);
lcd.print("Now you are");
lcd.gotoXY(0,1);
lcd.print(" hidden :(");
}
lcd.gotoXY(0,2);
lcd.print(String(now.year())+"."+String(now.month())+"."+String(now.day()));
lcd.gotoXY(0,3);
lcd.print(String(now.hour())+":"+String(now.minute())+":"+String(now.second()));
lcd.renderAll();
delay(1000);
}
P.s.: Unfortunately I have no other Arduino boards to test with, however nothing else seemed to cause these delays until now.
