GeekFactory TimeLib Library

This library contains Unix time routines and can be used as a software RTC on various microcontroller platforms. The library is itself very small in size and can be used in 8, 16 and 32 bit devices, including the AVR based arduino boards.

This work is based in Paul Stoffregen libraries for the Arduino platform.

Basic library usage

In order to use the library we need to call a function to set the time. Internally the time is kept in the unix format, so the library expects you to provide it in that format. Functions are provided for converting between human readable time/date and the Unix time.

The following snippet shows how to convert and set the TimeLib clock:

// Structure that holds human readable time information;structtimelib_tmtinfo;
// Variable to hold Unix timetimelib_tinitialt;
// Set time manually to 13:55:30 Jan 1st 2014tinfo.tm_year=14;
tinfo.tm_mon=1;
tinfo.tm_mday=1;
tinfo.tm_hour=13;
tinfo.tm_min=55;
tinfo.tm_sec=30;
// Convert time structure to timestampinitialt=timelib_make(&tinfo);
// Set system time countertimelib_set(initialt);
// Configure the library to update every daytimelib_set_provider(time_provider, TIME_SECS_PER_DAY);

Basic library example using arduino

/** GeekFactory - "Construye tu propia tecnologia" Distribucion de materiales para el desarrollo e innovacion tecnologica www.geekfactory.mx Example of the TimeLib library in Arduino. This code should display the time on the serial monitor. User can set the time on the tinfo structure. This is a basic example that shows how the library can be used as software only RTC.*/
#include"TimeLib.h"// Structure that holds human readable time information;structtimelib_tm tinfo;
timelib_t now, initialt;
// Store last time we sent the informationuint32_t last = 0;
voidsetup()
{
// Configure serial port
Serial.begin(115200);
while (!Serial);
// Set time manually to 13:55:30 Jan 1st 2014// YOU CAN SET THE TIME FOR THIS EXAMPLE HERE
tinfo.tm_year = 14;
tinfo.tm_mon = 1;
tinfo.tm_mday = 1;
tinfo.tm_hour = 13;
tinfo.tm_min = 55;
tinfo.tm_sec = 30;
// Convert time structure to timestamp
initialt = timelib_make(&tinfo);
// Set system time countertimelib_set(initialt);
// Configure the library to update / sync every day (for hardware RTC)timelib_set_provider(time_provider, TIMELIB_SECS_PER_DAY);
}
voidloop()
{
// Display the time every secondif (millis() - last > 1000) {
// Keep track of the time we last sent data to serial monitor
last = millis();
// Get the timestamp from the library
now = timelib_get();
// Convert to human readable formattimelib_break(now, &tinfo);
// Send to serial port
Serial.print(tinfo.tm_hour);
printDigits(tinfo.tm_min);
printDigits(tinfo.tm_sec);
Serial.print("");
Serial.print(tinfo.tm_mday);
Serial.print("");
Serial.print(tinfo.tm_mon);
Serial.print("");
Serial.print(tinfo.tm_year);
Serial.println();
}
}
voidprintDigits(int digits)
{
// utility function for digital clock display: prints preceding colon and leading 0
Serial.print(":");
if (digits < 10)
Serial.print('0');
Serial.print(digits);
}
timelib_ttime_provider()
{
// Prototype if the function providing time informationreturn initialt;
}

Project Objectives

Our library should fulfill the following goals:

• Code should be portable to other platforms
• Library should be compact and have minimal dependencies
• Library should not include C++ code

Supported devices

This library was developed/tested on the following boards:

• PIC24HJ128GA504 devices using MPLAB X and XC16 compilers
• Arduino UNO R3
• Arduino Mega 2560 R3
• Basic testing on ESP8266 boards

The library is meant to work in other CPU architectures where a C compiler is available, please tell us about your experience if you try it in other platforms.

Contact me

• Feel free to write for any inquiry: ruben at geekfactory.mx
• Check our website: https://www.geekfactory.mx