Time_Time
#include <TimeLib.h>

refreshCache hour( now ) hour( time_t ) hourFormat12
hourFormat12( time_t ) isAM( now ) isAM( time_t ) isPM
minute minute( time_t ) second
second( time_t ) day day( time_t ) weekday
weekday( time_t ) month month( time_t ) year
year( time_t )
Utils
breakTime makeTime
now setTime( time_t ) settime( ints ) adjustTime
timeStatus setSyncProvider setSyncInterval

/*H*******************************************************
  time.c - low level time and date functions
  Copyright (c) Michael Margolis 2009-2014
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  
  1.0  6  Jan 2010 - initial release
  1.1  12 Feb 2010 - fixed leap year calculation error
  1.2  1  Nov 2010 - fixed setTime bug (thanks to Korman for this)
  1.3  24 Mar 2012 - many edits by Paul Stoffregen: fixed timeStatus() to update
                     status, updated examples for Arduino 1.0, fixed ARM
                     compatibility issues, added TimeArduinoDue and TimeTeensy3
                     examples, add error checking and messages to RTC examples,
                     add examples to DS1307RTC library.
  1.4  5  Sep 2014 - compatibility with Arduino 1.5.7
********************************************************/
#if ARDUINO >= 100
#include <Arduino.h> 
#else
#include <WProgram.h> 
#endif
#include "TimeLib.h"

//************************* VARIABLES ************************************
static tmElements_t tm;          // a cache of time elements
static time_t cacheTime;   // the time the cache was updated
static uint32_t syncInterval = 300;  // time sync will be attempted after this many seconds


/*F******************************************************************** * **********************************************************************/ void refreshCache( time_t t ) { if( t != cacheTime ) { breakTime( t, tm ); cacheTime = t; } }
/*F******************************************************************** * hour now **********************************************************************/ int hour() { return( hour(now()) ); }
/*F******************************************************************** * hour for given time (time_t) **********************************************************************/ int hour( time_t t ) { refreshCache( t ); return( tm.Hour ); }
/*F******************************************************************** * hour now in 12 hour format **********************************************************************/ int hourFormat12() { return( hourFormat12( now() ) ); }
/*F******************************************************************** * hour for the given time in 12 hour format **********************************************************************/ int hourFormat12( time_t t ) { refreshCache( t ); if( tm.Hour == 0 ) return( 12 ); // 12 MIDNIGHT else if( tm.Hour > 12) return( tm.Hour - 12 ); else return( tm.Hour ); }
/*F******************************************************************** * returns true if time now is AM **********************************************************************/ uint8_t isAM() { return( !isPM( now() ) ); }
/*F******************************************************************** * returns true if given time is AM **********************************************************************/ uint8_t isAM( time_t t ) { return( !isPM( t ) ); }
/*F******************************************************************** * returns true if PM **********************************************************************/ uint8_t isPM() { return( isPM( now() ) ); }
/*F******************************************************************** * returns true if PM **********************************************************************/ uint8_t isPM( time_t t ) { return( (hour( t ) >= 12) ); }
/*F******************************************************************** * **********************************************************************/ int minute() { return minute(now()); }
/*F******************************************************************** * minute for the given time (time_t) **********************************************************************/ int minute( time_t t ) { refreshCache( t ); return( tm.Minute ); }
/*F******************************************************************** * **********************************************************************/ int second() { return( second( now() ) ); }
/*F******************************************************************** * second for the given time **********************************************************************/ int second( time_t t ) { refreshCache(t); return tm.Second; }
/*F******************************************************************** * **********************************************************************/ int day() { return( day( now() ) ); }
/*F******************************************************************** * day for the given time (0-6) **********************************************************************/ int day( time_t t ) { refreshCache(t); return tm.Day; }
/*F******************************************************************** * Sunday is day 1 **********************************************************************/ int weekday() { return( weekday( now() ) ); }
/*F******************************************************************** * **********************************************************************/ int weekday( time_t t ) { refreshCache(t); return tm.Wday; }
/*F******************************************************************** * **********************************************************************/ int month() { return month(now()); }
/*F******************************************************************** * month for the given time **********************************************************************/ int month( time_t t ) { refreshCache(t); return tm.Month; }
/*F******************************************************************** * as in Processing, the full four digit year: (2009, 2010 etc) **********************************************************************/ int year() { return year(now()); }
/*F******************************************************************** * year for the given time **********************************************************************/ int year( time_t t ) { refreshCache( t ); return( tmYearToCalendar( tm.Year) ); }
/*===================================================================== /* functions to convert to and from system time */ /* These are for interfacing with time services and are not normally needed in a sketch */ // leap year calculator expects year argument as years offset from 1970 #define LEAP_YEAR(Y) ( ((1970+(Y))>0) && !((1970+(Y))%4) && ( ((1970+(Y))%100) || !((1970+(Y))%400) ) ) static const uint8_t monthDays[]={31,28,31,30,31,30,31,31,30,31,30,31}; // API starts months from 1, this array starts from 0
/*F******************************************************************** * break given time_t into time components, this is a more compact version of the C library localtime function note that year is offset from 1970 !!! **********************************************************************/ void breakTime( time_t timeInput, tmElements_t &tm ) { uint8_t year; uint8_t month, monthLength; uint32_t time; unsigned long days; time = (uint32_t)timeInput; tm.Second = time % 60; time /= 60; // NOW IT IS MINUTES tm.Minute = time % 60; time /= 60; // NOW IT IS HOURS tm.Hour = time % 24; time /= 24; // NOW IT IS DAYS tm.Wday = ((time + 4) % 7) + 1; // SUNDAY IS DAY 1 year = 0; days = 0; while( (unsigned)(days += (LEAP_YEAR(year) ? 366 : 365)) <= time) year++; tm.Year = year; // YEAR IS OFFSET FROM 1970 days -= LEAP_YEAR(year) ? 366 : 365; time -= days; // NOW IT IS DAYS IN THIS YEAR, STARTING AT 0 days=0; month=0; monthLength=0; for( month =0; month < 12; month++) { if( month == 1) { // FEBRUARY if( LEAP_YEAR( year ) ) monthLength = 29; else monthLength=28; else monthLength = monthDays[month]; if( time >= monthLength ) time -= monthLength; else break; } } tm.Month = month + 1; // JAN IS MONTH 1 tm.Day = time + 1; // DAY OF MONTH }
/*F******************************************************************** * assemble time elements into time_t note year argument is offset from 1970 (see macros in time.h to convert to other formats) previous version used full four digit year (or digits since 2000),i.e. 2009 was 2009 or 9 **********************************************************************/ time_t makeTime( const tmElements_t &tm ) { int i; uint32_t seconds; // SECONDS FROM 1970 TILL 1 Jan 00:00:00 OF GIVEN YEAR seconds= tm.Year * (SECS_PER_DAY * 365); for( i = 0; i < tm.Year; i++) { if( LEAP_YEAR(i) ) seconds += SECS_PER_DAY; // ADD EXTRA DAYS FOR LEAP YEARS } // ADD DAYS FOR THIS YEAR, MONTHS START FROM 1 for( i = 1; i < tm.Month; i++) { if( (i == 2) && LEAP_YEAR(tm.Year)) seconds += SECS_PER_DAY * 29; else seconds += SECS_PER_DAY * monthDays[i-1];// MONTHdAY ARRAY STARTS AT 0 } seconds+= (tm.Day-1) * SECS_PER_DAY; seconds+= tm.Hour * SECS_PER_HOUR; seconds+= tm.Minute * SECS_PER_MIN; seconds+= tm.Second; return( (time_t)seconds ); } /*=====================================================*/ /* Low level system time functions */ static uint32_t sysTime = 0; static uint32_t prevMillis = 0; static uint32_t nextSyncTime = 0; static timeStatus_t Status = timeNotSet; getExternalTime getTimePtr; // POINTER TO EXTERNAL SYNC FUNCTION //setExternalTime setTimePtr; // NOT USED IN THIS VERSION #ifdef TIME_DRIFT_INFO // DEFINE THIS TO GET DRIFT DATA time_t sysUnsyncedTime = 0; // TIME SYStIME UNADJUSTED BY SYNC #endif
/*F******************************************************************** * CALCULATE NUMBER OF SECONDS PASSED SINCE LAST CALL TO NOW() **********************************************************************/ time_t now() { while( millis() - prevMillis >= 1000 ) { // millis() AND prevMillis ARE BOTH UNSIGNED INTS THUS SUBTRACTION // WILL ALWAYS BE ABSOLUTE VALUE OF DIFFERENCE sysTime++; prevMillis += 1000; #ifdef TIME_DRIFT_INFO sysUnsyncedTime++; // THIS CAN BE COMPARED TO THE SYNCED TIME TO // MEASURE LONG TERM DRIFT #endif } if( nextSyncTime <= sysTime) { if( getTimePtr != 0) { time_t t = getTimePtr(); if( t != 0) setTime(t); else { nextSyncTime = sysTime + syncInterval; Status = (Status == timeNotSet) ? timeNotSet : timeNeedsSync; } } } return( (time_t)sysTime ); }
/*F******************************************************************** * **********************************************************************/ void setTime( time_t t ) { #ifdef TIME_DRIFT_INFO if( sysUnsyncedTime == 0) sysUnsyncedTime = t; // STORE TIME OF FIRST CALL TO SET A VALID TIME #endif sysTime = (uint32_t)t; nextSyncTime = (uint32_t)t + syncInterval; Status = timeSet; prevMillis = millis(); // RESTART COUNTING FROM NOW (THANKS TO kORMAN // FOR THIS FIX) }
/*F******************************************************************** * year can be given as full four digit year or two digts (2010 or 10 for 2010); it is converted to years since 1970 **********************************************************************/ void setTime( int hr,int min,int sec,int dy, int mnth, int yr) { if( yr > 99) yr = yr - 1970; else yr += 30; tm.Year = yr; tm.Month = mnth; tm.Day = dy; tm.Hour = hr; tm.Minute = min; tm.Second = sec; setTime( makeTime( tm ) ); }
/*F******************************************************************** * **********************************************************************/ void adjustTime( long adjustment ) { sysTime += adjustment; }
/*F******************************************************************** * indicates if time has been set and recently synchronized **********************************************************************/ timeStatus_t timeStatus() { now(); // required to actually update the status return Status; }
/*F******************************************************************** * **********************************************************************/ void setSyncProvider( getExternalTime getTimeFunction) { getTimePtr = getTimeFunction; nextSyncTime = sysTime; now(); // THIS WILL SYNC CLOCK }
/*F******************************************************************** *set number of seconds between re-sync **********************************************************************/ void setSyncInterval( time_t interval) { syncInterval = (uint32_t)interval; nextSyncTime = sysTime + syncInterval; }