This is a fork of JeeLab's fantastic real time clock library for Arduino.
For a tutorial on using this library with an RTC module like the DS1307, PCF8523, or DS3231, see the guide at: https://learn.adafruit.com/ds1307-real-time-clock-breakout-board-kit/overview
For the detailed API documentation, see https://adafruit.github.io/RTClib/html/index.html
Works great with Adafruit RTC breakouts:
To install, use the Arduino Library Manager to search for "RTClib", find "RTClib by Adafruit" and install the library.
Please note that dayOfTheWeek() ranges from 0 to 6 inclusive with 0 being 'Sunday'.
| MCU | Tested Works | Doesn't Work | Not Tested | Notes |
|---|---|---|---|---|
| Atmega328 @ 16MHz | X | |||
| Atmega328 @ 12MHz | X | |||
| Atmega32u4 @ 16MHz | X | Use SDA/SCL on pins D3 & D2 | ||
| Atmega32u4 @ 8MHz | X | Use SDA/SCL on pins D3 & D2 | ||
| ESP8266 | X | SDA/SCL default to pins 4 & 5 but any two pins can be assigned as SDA/SCL using Wire.begin(SDA,SCL) | ||
| Atmega2560 @ 16MHz | X | Use SDA/SCL on Pins 20 & 21 | ||
| ATSAM3X8E | X | Use SDA1 and SCL1 | ||
| ATSAM21D | X | |||
| ATtiny85 @ 16MHz | X | |||
| ATtiny85 @ 8MHz | X | |||
| Intel Curie @ 32MHz | X | |||
| STM32F2 | X |
- ATmega328 @ 16MHz : Arduino UNO, Adafruit Pro Trinket 5V, Adafruit Metro 328, Adafruit Metro Mini
- ATmega328 @ 12MHz : Adafruit Pro Trinket 3V
- ATmega32u4 @ 16MHz : Arduino Leonardo, Arduino Micro, Arduino Yun, Teensy 2.0
- ATmega32u4 @ 8MHz : Adafruit Flora, Bluefruit Micro
- ESP8266 : Adafruit Huzzah
- ATmega2560 @ 16MHz : Arduino Mega
- ATSAM3X8E : Arduino Due
- ATSAM21D : Arduino Zero, M0 Pro
- ATtiny85 @ 16MHz : Adafruit Trinket 5V
- ATtiny85 @ 8MHz : Adafruit Gemma, Arduino Gemma, Adafruit Trinket 3V