09. RTC

The rtc object is a built-in object that provides the RTC alarm function.

Functional overview:

• Provides a function to raise an alarm event at a specified time.

Limitations:

• Only one alarm can be used.

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rtc Global Object

Methods()/Properties	Summary	Version	Note
rtc.setAlarm()	Sets the alarm occurrence time.
rtc.stopAlarm()	Releases the alarm.

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Details

rtc.setAlarm(rtcAlarm[,callback])

Sets the alarm occurrence time.
Executes callback processing when an alarm occurs.
The alarm continues until it is stopped.
This method does not allow multiple simultaneous uses.
If you want to set another time, you need to release it once.

Name	Type	M/O	Summary	Note
rtcAlarm	Object	mandatory	Alarm occurrence time setting hour : {number} Alarm occurrence time [hour] Range: 0 - 23) minute : {number} Alarm occurrence time [minute] Range: 0 - 59 second : {number} Alarm occurrence time [second] Range: 0 - 59 timeout : {number} (*1)	*1: Not use.
callback()	function	mandatory	Executes callback processing when an alarm occurs.
return	undefined	-	-	When an error occurs, an exception is raised.

rtc.stopAlarm()

Releases the alarm.

Name	Type/Object	M/O	Summary	Note
return	undefined	-	-

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Object Usage Examples

Sample1

This is a sample that generates an alarm.
Gets the current time and raises an RTC alarm 20 seconds after that time.

var MAX_COUNT = 5;
var count = MAX_COUNT;
var set_date;
var rtc_time;

var perAlarm = function() {
    rtc.stopAlarm();
    count--;
    print('alarm: count = ' + count);
    set_date = new Date();
    print('Now time: ' + set_date.toString());
    if(count > 0) {
        set_date.setSeconds(set_date.getSeconds() + 20);
        rtc_time = {    
            hour: set_date.getHours(),
            minute: set_date.getMinutes(),
            second: set_date.getSeconds()
        };
        rtc.setAlarm(rtc_time, perAlarm);
    }
}

perAlarm();

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Updated: 2022-10-25