Example Code for Arduino-Get and Set Time

Hardware Preparation

• DFR0216-2 DFRduino UNO R3 with IO Expansion Shield and USB Cable A-B x 1
• DFR0641 DS3231M MEMS Precise RTC Module x 1
• FIT0916-FF DuPont Wires x5

Software Preparation

• Download Arduino IDE: Click to download Arduino IDE
• Download the DFRobot_DS3231M library: DFRobot DS3231M library
• About how to install the library?

Wiring Diagram

Other Preparation Work

• Install the DS3231M Library in Arduino IDE.
• Connect the DS3231M module to the Arduino UNO R3 using jumper wires as per the Wiring Diagram.

Sample Code

    /*!
     * @file getTimeAndTemperature.ino
     * @brief Show current time 
     * @n Experiment phenomenon: read data every 1 seconds and print it on serial port. 
     *
     * @copyright	Copyright (c) 2010 DFRobot Co.Ltd (https://www.dfrobot.com)
     * @licence     The MIT License (MIT)
     * @author [LuoYufeng]([email protected])
     * @version  V0.1
     * @date  2019-08-19
     * @url https://github.com/DFRobot/DFRobot_DS3231M
     */
    #include "DFRobot_DS3231M.h"
    
    DFRobot_DS3231M rtc;
    
    
    void setup(void)
    {
        Serial.begin(9600);
        /*Wait for the chip to be initialized completely, and then exit*/
        while(rtc.begin() != true){
            Serial.println("Failed to init chip, please check if the chip connection is fine. ");
            delay(1000);
        }
        /*!
         *@brief Set the vaule of pin sqw
         *@param mode eDS3231M_OFF             = 0x01 // Not output square wave, enter interrupt mode
         *@n          eDS3231M_SquareWave_1Hz  = 0x00 // 1Hz square wave
         *@n          eDS3231M_SquareWave_1kHz = 0x08 // 1kHz square wave
         *@n          eDS3231M_SquareWave_4kHz = 0x10 // 4kHz square wave
         *@n          eDS3231M_SquareWave_8kHz = 0x18 // 8kHz square wave
         */
        rtc.writeSqwPinMode(eDS3231M_SquareWave_1Hz);
        /*!
         *@brief Read the value of pin sqw
         *@return mode eDS3231M_OFF             = 0x01 // Off
         *@n           eDS3231M_SquareWave_1Hz  = 0x00 // 1Hz square wave
         *@n           eDS3231M_SquareWave_1kHz = 0x08 // 1kHz square wave
         *@n           eDS3231M_SquareWave_4kHz = 0x10 // 4kHz square wave
         *@n           eDS3231M_SquareWave_8kHz = 0x18 // 8kHz square wave
         */
        //rtc.readSqwPinMode();
        /*!
         *@brief Set the last compiled time as the current time
         */
        //rtc.dateTime();//If users use this function, please don't set time by other way
        rtc.setYear(19);//Set year, default in the 21st century, input negative number for years in the 20th century.
        rtc.setMonth(10);
        rtc.setDate(23);
        /*!
         *@brief Set the hours and 12hours or 24hours
         *@param hour:1-12 in 12hours,0-23 in 24hours
         *@param mode:e24hours, eAM, ePM
         */
        rtc.setHour(0,e24hours);
        rtc.setMinute(59);
        rtc.setSecond(40);
        
        rtc.adjust();
    
        /*!
         *@brief enable the 32k output (default is enable)
         */
        //rtc.disAble32k();
    
        /*!
         *@brief disable the 32k output 
         */
        //rtc.enAble32k();
    }
    
    void loop() {
        /*!
         *@brief Get current time data 
         *@return Current time data
         */
        rtc.getNowTime();
        Serial.print(rtc.year(), DEC);//year
        Serial.print('/');
        Serial.print(rtc.month(), DEC);//month
        Serial.print('/');
        Serial.print(rtc.day(), DEC);//date
        Serial.print(" (");
        Serial.print(rtc.getDayOfTheWeek());//day of week
        Serial.print(") ");
        Serial.print(rtc.hour(), DEC);//hour
        Serial.print(':');
        Serial.print(rtc.minute(), DEC);//minute
        Serial.print(':');
        Serial.print(rtc.second(), DEC);//second
        Serial.print(' ');
        /*if rtc works in 24hours mode,this function doesn't print anything*/
        Serial.print(rtc.getAMorPM());
        Serial.println();
        Serial.print("Temperature: ");
        /*!
         *@brief Get current temperature
         *@return Current temperautre, unit: ℃ 
         */
        Serial.print(rtc.getTemperatureC());
        Serial.println(" C");
        delay(1000);
    	
        /*!
         *@brief Judge if it is power-down
         *@return If retrun true, power down, needs to reset time; false, work well.
         */
        if (rtc.lostPower()) {
            Serial.println("RTC lost power, plrase reset the time!");
        }
    }

Result

Serial port print time.

Additional Information

NOTE: The accuracy of the internal temeprature compensator is for normal temperature detection. If your application requires high accuracy temperature measurement, you may want to add an extra temperature sensor with higher accuracy.