RtcDateTime currentTime = rtcObject.GetDateTime() //get the time from the RTCĬhar str //declare a string as an array of chars

RtcDS3231 rtcObject(Wire) //Uncomment for version 2.0.0 of the rtc library RtcDS3231 rtcObject //Uncomment for version 1.0.1 of the rtc library In the end of the main loop, we put a delay of 20 seconds. Once we have all the information of date and time on a string, we send it to the serial port, to get the output on the serial console of the Arduino IDE. We will use those methods to get them and print them to a string (using the sprintf function). The RtcDateTime class has a method for getting each of the parameters of date and time. This method will return a RtcDateTime object, as we used before in the setup function.

To get a the current time and date, we call the GetDateTime method on our previously defined RtcDS3231 object (which we named “rtcObject”). In this simple example, we will poll the RTC every 20 seconds. RtcObject.SetDateTime(currentTime) //configure the RTC with objectįinally, we will read the current date and time from the RTC in the main loop function. RtcDateTime currentTime = RtcDateTime(16, 05, 18, 21, 20, 0) //define date and time object

Serial.begin(115200) //Starts serial connection So, we use the library shown in figure 3 which, as stated in the description, is tested on the ESP8266. Software LibraryĪs usual, the Arduino Environment provides a wide range of libraries to interface with different devices, and the DS3231 is no exception. The tests were performed using a NodeMCU board, a very cheap and easy to use ESP8266 board.

If you are using a NodeMCU board, take into consideration that the board pins don’t correspond to the ESP8266 pins (check here the correct mapping). Since we are using the Arduino IDE, we have the Wire library available to handle the I2C protocol in the ESP8266, which we will later use when creating the program to interact with the RTC.Īs described in the documentation of the ESP8266 libraries for the Arduino IDE, the default pins for the I2C in the Wire library are pins 4 (SDA) and 5 (SDL). Figure 2 – Connection diagram between the ESP8266 and the DS3231.Īs can be seen in the diagram, the DS3231 uses an I2C interface to interact with microcontrollers.

Wire library for esp8266