The new code is here:
// Date and time functions using a DS1307 RTC connected via I2C and Wire lib
#include <Wire.h>
#include <RTClib.h>
RTC_DS1307 RTC;
void setup () {
Serial.begin(57600);
Wire.begin();
RTC.begin();
if (! RTC.isrunning()) {
Serial.println("RTC is NOT running!");
// following line sets the RTC to the date & time this sketch was compiled
//RTC.adjust(DateTime(__DATE__, __TIME__));
}
}
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();
Serial.print(" since 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.unixtime() + 7 * 86400L + 30);
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);
}
It uses a library called RTClib from jeelabs.org. Here is RTClib.h:
// Code by JeeLabs http://news.jeelabs.org/code/
// Released to the public domain! Enjoy!
// Simple general-purpose date/time class (no TZ / DST / leap second handling!)
class DateTime {
public:
DateTime (uint32_t t =0);
DateTime (uint16_t year, uint8_t month, uint8_t day,
uint8_t hour =0, uint8_t min =0, uint8_t sec =0);
DateTime (const char* date, const char* time);
uint16_t year() const { return 2000 + yOff; }
uint8_t month() const { return m; }
uint8_t day() const { return d; }
uint8_t hour() const { return hh; }
uint8_t minute() const { return mm; }
uint8_t second() const { return ss; }
uint8_t dayOfWeek() const;
// 32-bit times as seconds since 1/1/2000
long secondstime() const;
// 32-bit times as seconds since 1/1/1970
uint32_t unixtime(void) const;
protected:
uint8_t yOff, m, d, hh, mm, ss;
};
// RTC based on the DS1307 chip connected via I2C and the Wire library
class RTC_DS1307 {
public:
static uint8_t begin(void);
static void adjust(const DateTime& dt);
uint8_t isrunning(void);
static DateTime now();
};
// RTC using the internal millis() clock, has to be initialized before use
// NOTE: this clock won't be correct once the millis() timer rolls over (>49d?)
class RTC_Millis {
public:
static void begin(const DateTime& dt) { adjust(dt); }
static void adjust(const DateTime& dt);
static DateTime now();
protected:
static long offset;
};
...cont/ next post