Time and TimeAlarms Libraries – Ask here for help or suggestions

No errors were reported with the the beta code so the playground download has been updated.

Check my project at http://arduino.cc/forum/index.php/topic,67127.0.html

I javel thé sketch and à sérial interface also have a jquery web interface

mem:
Time and TimeAlarms are libraries for handling time and time based tasks on Arduino. The code can be found here.

This thread is for help on how to use these libraries and suggestions for future improvements.

A thread specifically for discussing issues relating to updates in the beta test version can be found here (that thread will be closed after the beta testing is completed.

Hello mem,
I needed to use DS1307 Real-Time Clock on a project and saw the Time library, but I thought it was too big for what I needed (just to know day, month, year, hour, minute and second from DS1307), so I decided to create a new, simple library to achieve this task and its code is at GitHub:

I think we should integrate it, maybe creating a "driver interface" (just some conventions) so we can create drivers for many RTC chips and use the same code. What do you think?

Other thing I think that should be changed in Time library is the namespace of functions. Maybe using Time.hour(), Time.day() etc. instead of directly hour(), day() etc.

alvarojusten:
Hello mem,
I needed to use DS1307 Real-Time Clock on a project and saw the Time library, but I thought it was too big for what I needed (just to know day, month, year, hour, minute and second from DS1307), so I decided to create a new, simple library to achieve this task and its code is at GitHub:

GitHub - turicas/DS1307: Arduino library for reading and setting date and time for the DS1307 Real-Time Clock IC

I think we should integrate it, maybe creating a "driver interface" (just some conventions) so we can create drivers for many RTC chips and use the same code. What do you think?

Other thing I think that should be changed in Time library is the namespace of functions. Maybe using Time.hour(), Time.day() etc. instead of directly hour(), day() etc.

Hi alvarojusten

Thank you for sharing your library. I have seen many DS1037 Arduino libraries and yours is one of the simplest (that’s a compliment). It does use less flash memory than the Time library but it actually seems to use more data (your sketch uses 540 bytes of RAM, the Time library code posted below uses 482 bytes of RAM).

/*
 *  A simple sketch to display time from a DS1307 RTC
 * 
 */

#include <Time.h>  
#include <Wire.h>  
#include <DS1307RTC.h>  // a basic DS1307 library that returns time as a time_t

char dateTime[20];

void setup()  {
  Serial.begin(9600);     
}

void loop()
{
   setTime(RTC.get());
   sprintf(dateTime, "%4d-%02d-%02d %02d:%02d:%02d", year(),
            month(), day(), hour(),minute(), second()) ;
    Serial.print(dateTime);
    Serial.print(" - day of week: ");
    Serial.println(dayStr(weekday()));

   delay(1000);
}

Here are some advantage of using the Time library version:

  • You can easily calculate the difference between two times
  • The time format is based on a standard that almost every programming platform can handle
  • The same sketch code can be used with a selection of time sources such as RTC, NTP( internet time standards), Radio Clocks, GPS …
  • You can use the TimeAlarms library to add timers and time of day alarms.

Hi [again], Mem.

how to convert now() function (=>unixtime) to character array (char[11])?Is it possible to do?

Many C compilers have a function named ctime that produces a date string but I don't think its available with the arduino tools. I have always used multiple print statements to display the data, is there a reason you can't do that for your application?

ctime is not found in - avr-libc: AVR Libc -

maybe this link helps - time.c - sanos source -

Rob, did you try to use it in the Arduino IDE?
If so, a brief example would be useful.

No,

however I did use the RTC lib for the DS1307 - - GitHub - adafruit/RTClib: A fork of Jeelab's fantastic RTC Arduino library - It includes a DateTime Class that has all needed to implement a time2string(...) function
Note DateTime is year 2000 based, the essential code is in the DateTime constructor that can be transformend quite easily, see below:

void setup()
{
  Serial.begin(115200);
  Serial.println("UnixTime simulator :) ");
}

void loop()
{
  char buffer[20];
  time2string(millis(), buffer);
  Serial.print(millis());
  Serial.print(" ==>  ");
  Serial.println(buffer);
}

uint8_t daysInMonth [] = { 31,28,31,30,31,30,31,31,30,31,30,31 };

void time2string(unsigned long t, char *buf)
{
  uint8_t yOff, m, d, hh, mm, ss;

  ss = t % 60;
  t /= 60;
  mm = t % 60;
  t /= 60;
  hh = t % 24;
  uint16_t days = t / 24;
  uint8_t leap;
  for (yOff = 0; ; ++yOff) {
        leap = yOff % 4 == 0;
        if (days < 365 + leap)
            break;
        days -= 365 + leap;
  }
  for (m = 1; ; ++m) {
    uint8_t daysPerMonth = daysInMonth[ m - 1];
    if (leap && m == 2)
      ++daysPerMonth;
    if (days < daysPerMonth)
        break;
    days -= daysPerMonth;
  }
  d = days + 1;
  sprintf(buf,"%4d-%02d-%02d %02d:%02d:%02d", 1970+yOff, m,d, hh,mm,ss);
}

thanks Rob, Mem..

Many C compilers have a function named ctime that produces a date string but I don't think its available with the arduino tools. I have always used multiple print statements to display the data, is there a reason you can't do that for your application?

My Goal is sending unixtime via Wireless, then I have data in char array (char[11])
so when i try to send data unixtime which it is unsigned long, the compiler give error message:

incompatible types in assignment of 'time_t' to 'char [11]'

Rob, I use Mem's library (Time, TimeAlarm, DS1307RTC)..Any suggestion how to do it for DS1307RTC library?thanks anyway for the help.

thanks a lot.

do you mean some thing like this?

#include "stdlib.h"

void setup()
{
  Serial.begin(115200);
  char buffer[11];
  unsigned long unixtime=1234567890L;  // L for long
  ltoa(unixtime, buffer, 10);
  Serial.println(buffer); 
}

void loop(){}

(code not tested)

see - avr-libc: <stdlib.h>: General utilities - search for ltoa

UPDATE
-- added void before loop()

robtillaart:
do you mean some thing like this?

#include "stdlib.h"

void setup()
{
  Serial.begin(115200);
  char buffer[11];
  unsigned long unixtime=1234567890L;  // L for long
  ltoa(unixtime, buffer, 10);
  Serial.println(buffer);
}

loop(){}



(code not tested)

see - http://www.nongnu.org/avr-libc/user-manual/group__avr__stdlib.html - search for ltoa

FOOL me, i tried it, but i didn't print the buffer..
Thanks, a lot..i'll try tomorrow. now, 3.05am..here..need a sleep..aha!

you need to add void before loop(){}

allready patched in posting above.

robtillaart:
you need to add void before loop(){}

allready patched in posting above.

the code just works..thanks, rob..
ltoa and atol will be my new friends..LOL..

welcome,

surf one evening over the - avr-libc: <stdlib.h>: General utilities - site and you learn thousand new possibilities :wink:

How to check alarm time on timeAlarm library?
it is possible to know the "alarm ID" is enable or disable?
I got this code from the old forum

void checkAlarm(){

  showAlarmTime(ID1);
  showAlarmTime(ID2);
  showAlarmTime(ID3);
  showAlarmTime(ID4);
  showAlarmTime(ID5);
  showAlarmTime(ID6);

  Serial.println("----------------------------------------------------");
}//checkAlarm

void showAlarmTime(AlarmID_t id){
  time_t alarmTime = Alarm.read(id);
  if(alarmTime != 0)
  {
    if( alarmTime <= SECS_PER_DAY)  
      Serial.print(" repeat alarm with ID ");
    else  
      Serial.print(" once only alarm with ID  ");
    Serial.print(id, DEC);    
    Serial.print(" set for ");
    digitalClockDisplay1(alarmTime);
  }
}//showAlarmTime

but, i guess those code doesn't show the alarm is disabled or enabled.
thanks for any suggestions.
regards,
nug.

it is possible to know the "alarm ID" is enable or disable?

How does the alarm become enabled or disabled? Your code does that. Make your code remember that status it set the alarm to. You need to keep track of the alarm IDs, so a structure that linked alarm ID and status should be easy to implement.

struct alarmData
{
   int alarmID;
   bool armed;
};
typedef struct alarmData AlarmData;
AlarmData ad;
ad.alarmID = ?; // Assign the alarm ID
ad.armed = false; // It is not enabled

Whenever you change state, set the structure member, too.

Hi, I've been using the Time library for a while just based on the arduinos timers. My sketch has functions to setTime() and uses now() to get it. I sometimes want to set the time to something specific for testing but having the RTC time as default is best.
I've picked some code out of the examples to get the time from the RTC when the sketch starts.

  setSyncProvider(RTC.get);   // the function to get the time from the RTC
  if(timeStatus()!= timeSet) {
     Serial.println("Unable to sync with the RTC");
  }
  else{
    Serial.println("RTC has set the system time");      
  }
  digitalClockDisplay(now());     cout<<endl;

If I later call setTime() with my test time it seems to stay set but I worry that some synch function might bite me when I call now() - will it? what it i don't setSyncProvider - can i get the RTC time into the library without doing that?

Also, thank you for the library - it's been a great help.

I didn't find this thread until after I already posted here:

I'm trying to figure out how Time handles the situation when millis() rolls over but I'm not getting it. I'd love a nudge in the right direction.

Cheers!

Hi,

I'm trying to use the Time library with arduino 1.0-beta4 for OSX (library is located at ~willem/Documents/Arduino/Libraries/Time) when I compile I get

UdpNtpClient_WE.cpp:1:18: error: Time.h: No such file or directory

I guess something has changed for IDE 1.0 (beta) .... who knows the solution ?

Cheers, Willem.