Real Time Clock (RTC)

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Clock (RTC)
SoftwareSerial
Utility

This library allows users to get a clock after setting the year, month, date, hour, minutes, and seconds. To use this library, create an instance like "RTC rtc" and describe #include <RTC.h>

begin

Description

Initialize RTC.

Syntax

bool rtc.begin()

Parameters

None

Returns

True or False

end

Description

Stop RTC.

Syntax

bool rtc.end()

Parameters

None

Returns

True or False

setDateTime

Description

Set a start time.

Syntax

bool rtc.setDateTime(int year, int mon, int day, int hour, int min, int sec, int week)

Parameters

year: Year
mon: Month
day: Day
hour: Hour
min: Minute
sec: Second
week: Use the following parameters:
  RTC_WEEK_SUNDAY
  RTC_WEEK_MONDAY
  RTC_WEEK_TUESDAY
  RTC_WEEK_WEDNESDAY
  RTC_WEEK_THURSDAY
  RTC_WEEK_FRIDAY
  RTC_WEEK_SATURDAY

Returns

True or False

getDateTime

Description

Get a current time.

Syntax

bool rtc.getDateTime(int &year, int &mon, int &day, int &hour, int &min, int &sec, int &week)

Parameters

Variables are the same as setDateTime.

Returns

Variables same as setDateTime.

attachAlarmHandler

Description

Register a function when an alarm occurs.

Syntax

void rtc.attachAlarmHandler(void (*function)(void))

Parameters

function: Function to be called when an alarm occurs

Returns

None

setAlarmTime

Description

Set an alarm time

Syntax

bool rtc.setAlarmTime (int hour, int min, int week_flag)

Parameters

hour: Hour
min: Minute
week_flag: Use the following week parameters:
  RTC_ALARM_SUNDAY
  RTC_ALARM_MONDAY
  RTC_ALARM_TUESDAY
  RTC_ALARM_WEDNESDAY
  RTC_ALARM_THURSDAY
  RTC_ALARM_FRIDAY
  RTC_ALARM_SATURDAY
  RTC_ALARM_EVERYDAY

Returns

True or False

alarmOn

Description

Set alarm on.

Syntax

rtc.alarmOn()

Parameters

None

Returns

None

alarmOff

Description

Set alarm off.

Syntax

rtc.alarmOff()

Parameters

None

Returns

None

Program for setting a time and alarm. Time and alarm notification by flashing LED.

        #include <Arduino.h>
        #include <RTC.h>
         
        #define LED_ERROR 12
        #define LED_ALARM 13
        #define LED_ON HIGH
        #define LED_OFF LOW
         
        RTC rtc;
        void alarm_handler();
         
        void setup()
        {
          Serial.begin(9600);
          pinMode(LED_ALARM, OUTPUT); // LED for alarm
          pinMode(LED_ERROR, OUTPUT); // LED for error
          digitalWrite(LED_ALARM, LED_OFF); //turn off
          digitalWrite(LED_ERROR, LED_OFF); //turn off
           
          if(!rtc.begin()){
            digitalWrite(LED_ERROR, LED_ON); // error
          }  
          rtc.setDateTime(2016, 9, 22, 23, 20, 50, RTC_WEEK_SATURDAY);
           
          rtc.attachAlarmHandler(alarm_handler);
          rtc.setAlarmTime(23, 21, RTC_ALARM_EVERYDAY);
          rtc.alarmOn();
           
        }
           
        void loop()
        {
          int year, mon, day, hour, min, sec, week;
          rtc.getDateTime(year, mon, day, hour, min, sec, week);
           
          Serial.print(year, DEC);Serial.print("/");
          Serial.print(mon, DEC); Serial.print("/");
          Serial.print(day, DEC); Serial.print(" ");
          Serial.print(hour, DEC); Serial.print(":");
          Serial.print(min, DEC); Serial.print(":");
          Serial.println(sec, DEC);
           
          delay(500);
           
        }
           
        void alarm_handler()
        {
          digitalWrite(LED_ALARM, LED_ON); // led for alarm
        }