Real Time Clock (RTC)

Digital I/O
Analog I/O
Advanced I/O
Time
Math
Trigonometry
Random Numbers
Bits and Bytes
Interrupts
Serial Comm.

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Clock (RTC)
Utility

This library allows users to get a clock after setting the year, month, date, hour, minutes, and seconds. The specified function can be called by setting the alarm feature. To use this library, describe #include <RTC.h>

rtc_init

Description

Initialize RTC.

Syntax

int rtc_init()

Parameters

None

Returns

0: False, 1: Success, 2: Already initialized

rtc_deinit

Description

Stop RTC.

Syntax

int rtc_deinit()

Parameters

None

Returns

0: False, 1: Success

rtc_set_time

Description

Set a start time.

Syntax

int rtc_set_time(RTC_TIMETYPE *time)

Parameters

time: Specify the RTC_TIMETYPE structure for setting a time(Note)

Returns

0: False, 1: Success

Note

Refer to the sample program for setting a time.

rtc_get_time

Description

Get a current time

Syntax

int rtc_get_time(RTC_TIMETYPE *time)

Parameters

time: Specify the RTC_TIMETYP structure for storing a time.

Returns

0: False, 1: Success

rtc_attach_alarm_handler

Description

Register a function when an alarm occurs

Syntax

rtc_attach_alarm_handler(void(*)(void) function)

Parameters

function: Function to be called when a alarm occurs.

Returns

None

rtc_set_alarm_time

Description

Set an alarm time.

Syntax

int rtc_set_alarm_time (int hour, int min, int week_flag)

Parameters

hour: Hour
min: Minute
week_flag: Week(Specify multiple flags by using OR)

Returns

0: False, 1: Success

rtc_alarm_on

Description

Set alarm on.

Syntax

rtc_alarm_on()

Parameters

None

Returns

None

rtc_alarm_off

Description

Set alarm off.

Syntax

rtc_alarm_off()

Parameters

None

Returns

None

Macro Definition

Week for Setting Time

RTC_WEEK_SUNDAY: 0x00
RTC_WEEK_MONDAY: 0x01
RTC_WEEK_TUESDAY: 0x02
RTC_WEEK_WEDNESDAY: 0x03
RTC_WEEK_THURSDAY: 0x04
RTC_WEEK_FRIDAY: 0x05
RTC_WEEK_SATURDAY: 0x06

Week for Setting Alarm

RTC_ALARM_SUNDAY: 0x01
RTC_ALARM_MONDAY: 0x02
RTC_ALARM_TUESDAY: 0x04
RTC_ALARM_WEDNESDAY: 0x08
RTC_ALARM_THURSDAY: 0x10
RTC_ALARM_FRIDAY: 0x20
RTC_ALARM_SATURDAY: 0x40
RTC_ALARM_EVERYDAY: All of the above OR

rtc_attach_constant_period_interrupt_handler

Description

Register a function that operates periodically.

Syntax

rtc_attach_constant_period_interrupt_handler(function)

Parameters

function: A function to be called periodically

Returns

None

rtc_set_constant_period_interrupt_time

Description

Specify the periodic interval.

Syntax

int rtc_set_constant_period_interrupt_time(period);

Parameters

period:
RTC_CONSTANT_PERIOD_TIME_NONE : No period
RTC_CONSTANT_PERIOD_TIME_HALFSECOND : 0.5 sec
RTC_CONSTANT_PERIOD_TIME_1SECOND : 1 sec(default)
RTC_CONSTANT_PERIOD_TIME_1MINUTE : 1 min
RTC_CONSTANT_PERIOD_TIME_1HOUR : 1 hour
RTC_CONSTANT_PERIOD_TIME_1DAY : 1 day
RTC_CONSTANT_PERIOD_TIME_1MONTH : 1 week

Returns

None

rtc_constant_period_interrupt_on

Description

Set a periodic function on.

Syntax

rtc_constant_period_interrupt_on()

Parameters

None

Returns

None

rtc_constant_period_interrupt_off

Description

Set a periodic function off.

Syntax

rtc_constant_period_interrupt_off()

Parameters

None

Returns

None

---

Program for setting a time and alarm. Time and alarm notification is output via serial communication.

#include <Arduino.h>
#include <RTC.h>
 
void alarm_handler();
RTC_TIMETYPE t;
 
void setup()
{
  Serial.begin(9600);
  pinMode(PIN_LED0, OUTPUT); //blue led for alarm
  digitalWrite(PIN_LED0, HIGH); //turn off
  int err = rtc_init();
 
  t.year    = 2016;
  t.mon     = 3;
  t.day     = 22;
  t.weekday = RTC_WEEK_TUESDAY;
  t.hour    = 9;
  t.min     = 20;
  t.second  = 50;
 
  err = rtc_set_time(&t);
  rtc_attach_alarm_handler(alarm_handler);
  err = rtc_set_alarm_time(t.hour, t.min + 1);
 
}
 
void loop()
{
  int err;
  err = rtc_get_time(&t);
 
  Serial.print(t.year, DEC);Serial.print("/");
  Serial.print(t.mon, DEC); Serial.print("/");
  Serial.print(t.day, DEC); Serial.print(" ");
  Serial.print(t.hour, DEC); Serial.print(":");
  Serial.print(t.min, DEC); Serial.print(":");
  Serial.println(t.second, DEC);
 
  delay(500);
 
}
 
void alarm_handler()
{
  digitalWrite(PIN_LED0, LOW);//blue led for alarm
 
}