deveth0/Alarm_Demo.ino

## Alarm_Demo.ino
/**
 *  Sets an alarm using a DS3231 device, goes to sleep and wakes up again
 * @author: dev-eth0
 * @url: https://www.dev-eth0.de/
 */

#include <DS3231.h> // https://github.com/NorthernWidget/DS3231
#include <Wire.h>
#include <LowPower.h> // https://github.com/rocketscream/Low-Power

DS3231 Clock;

// Some static test-date for the RTC
byte Year = 2017;
byte Month = 9;
byte Date = 17;
byte Hour = 19;
byte Minute = 29;
byte Second = 30;

// Interrupt Pin used
static const byte wakeUpPin = 2;


// Those are the ALARM Bits that can be used
// They need to be combined into a single value (see below)
// Found here: https://github.com/mlepard/ArduinoChicken/blob/master/roboCoop/alarmControl.ino
#define ALRM1_MATCH_EVERY_SEC  0b1111  // once a second
#define ALRM1_MATCH_SEC        0b1110  // when seconds match
#define ALRM1_MATCH_MIN_SEC    0b1100  // when minutes and seconds match
#define ALRM1_MATCH_HR_MIN_SEC 0b1000  // when hours, minutes, and seconds match

#define ALRM2_ONCE_PER_MIN     0b111   // once per minute (00 seconds of every minute)
#define ALRM2_MATCH_MIN        0b110   // when minutes match
#define ALRM2_MATCH_HR_MIN     0b100   // when hours and minutes match

int ledState = HIGH;

void setup() {
  // Start the serial port
  Serial.begin(115200);
  Serial.println("Alarm Test");

  // Configure Interrupt Pin
  pinMode(wakeUpPin, INPUT_PULLUP);
  digitalWrite(wakeUpPin, HIGH);

  // Start the I2C interface
  Wire.begin();

  // Set time
  Clock.setClockMode(false);
  Clock.setYear(Year);
  Clock.setMonth(Month);
  Clock.setDate(Date);
  Clock.setHour(Hour);
  Clock.setMinute(Minute);
  Clock.setSecond(Second);

  // Set alarm
  Serial.println("Setting alarm");

  // This is the interesting part which sets the AlarmBits and configures, when the Alarm be triggered
  byte ALRM1_SET = ALRM1_MATCH_MIN_SEC; // trigger A1 when minute and second match
  byte ALRM2_SET = ALRM2_MATCH_MIN;     // trigger A2 when minute matches (and second is 0 as A2 does not support seconds)

  // combine the AlarmBits
  int ALARM_BITS = ALRM2_SET;
  ALARM_BITS <<= 4;
  ALARM_BITS |= ALRM1_SET;

  // Trigger Alarm when Minute == 30 or 0
  // Clock.setA1Time(Day, Hour, Minute, Second, AlarmBits, DayOfWeek, 12 hour mode, PM)
  Clock.setA1Time(0, 0, 0, 0, ALARM_BITS, false, false, false);
  // Clock.setA2Time(Day, Hour, Minute, AlarmBits, DayOfWeek, 12 hour mode, PM)
  Clock.setA2Time(0, 0, 30, ALARM_BITS, false, false, false);

  // Turn on Alarm
  Clock.turnOnAlarm(1);
  Clock.turnOnAlarm(2);

  Serial.println(ALARM_BITS, BIN);
  Serial.println("Alarm 1:");
  Serial.println(Clock.checkAlarmEnabled(1));
  Serial.println("Alarm 2:");
  Serial.println(Clock.checkAlarmEnabled(2));

  // Attach interrupt
  attachInterrupt(digitalPinToInterrupt(wakeUpPin), wakeUp, FALLING);

  // sleep
  delay(500);
  LowPower.powerDown(SLEEP_FOREVER, ADC_OFF, BOD_OFF);
}

// loop is started once the device wakes up again
void loop() {
  blinkLED();
  delay(1000);
}

void blinkLED() {
  if (ledState == LOW) {
    ledState = HIGH;
  } else {
    ledState = LOW;
  }
  digitalWrite(LED_BUILTIN, ledState);
}

void wakeUp() {
  // wake up again
  Serial.println("Woke up this morning...");
}
	/**
	* Sets an alarm using a DS3231 device, goes to sleep and wakes up again
	* @author: dev-eth0
	* @url: https://www.dev-eth0.de/
	*/

	#include <DS3231.h> // https://github.com/NorthernWidget/DS3231
	#include <Wire.h>
	#include <LowPower.h> // https://github.com/rocketscream/Low-Power

	DS3231 Clock;

	// Some static test-date for the RTC
	byte Year = 2017;
	byte Month = 9;
	byte Date = 17;
	byte Hour = 19;
	byte Minute = 29;
	byte Second = 30;

	// Interrupt Pin used
	static const byte wakeUpPin = 2;


	// Those are the ALARM Bits that can be used
	// They need to be combined into a single value (see below)
	// Found here: https://github.com/mlepard/ArduinoChicken/blob/master/roboCoop/alarmControl.ino
	#define ALRM1_MATCH_EVERY_SEC 0b1111 // once a second
	#define ALRM1_MATCH_SEC 0b1110 // when seconds match
	#define ALRM1_MATCH_MIN_SEC 0b1100 // when minutes and seconds match
	#define ALRM1_MATCH_HR_MIN_SEC 0b1000 // when hours, minutes, and seconds match

	#define ALRM2_ONCE_PER_MIN 0b111 // once per minute (00 seconds of every minute)
	#define ALRM2_MATCH_MIN 0b110 // when minutes match
	#define ALRM2_MATCH_HR_MIN 0b100 // when hours and minutes match

	int ledState = HIGH;

	void setup() {
	// Start the serial port
	Serial.begin(115200);
	Serial.println("Alarm Test");

	// Configure Interrupt Pin
	pinMode(wakeUpPin, INPUT_PULLUP);
	digitalWrite(wakeUpPin, HIGH);

	// Start the I2C interface
	Wire.begin();

	// Set time
	Clock.setClockMode(false);
	Clock.setYear(Year);
	Clock.setMonth(Month);
	Clock.setDate(Date);
	Clock.setHour(Hour);
	Clock.setMinute(Minute);
	Clock.setSecond(Second);

	// Set alarm
	Serial.println("Setting alarm");

	// This is the interesting part which sets the AlarmBits and configures, when the Alarm be triggered
	byte ALRM1_SET = ALRM1_MATCH_MIN_SEC; // trigger A1 when minute and second match
	byte ALRM2_SET = ALRM2_MATCH_MIN; // trigger A2 when minute matches (and second is 0 as A2 does not support seconds)

	// combine the AlarmBits
	int ALARM_BITS = ALRM2_SET;
	ALARM_BITS <<= 4;
	ALARM_BITS \|= ALRM1_SET;

	// Trigger Alarm when Minute == 30 or 0
	// Clock.setA1Time(Day, Hour, Minute, Second, AlarmBits, DayOfWeek, 12 hour mode, PM)
	Clock.setA1Time(0, 0, 0, 0, ALARM_BITS, false, false, false);
	// Clock.setA2Time(Day, Hour, Minute, AlarmBits, DayOfWeek, 12 hour mode, PM)
	Clock.setA2Time(0, 0, 30, ALARM_BITS, false, false, false);

	// Turn on Alarm
	Clock.turnOnAlarm(1);
	Clock.turnOnAlarm(2);

	Serial.println(ALARM_BITS, BIN);
	Serial.println("Alarm 1:");
	Serial.println(Clock.checkAlarmEnabled(1));
	Serial.println("Alarm 2:");
	Serial.println(Clock.checkAlarmEnabled(2));

	// Attach interrupt
	attachInterrupt(digitalPinToInterrupt(wakeUpPin), wakeUp, FALLING);

	// sleep
	delay(500);
	LowPower.powerDown(SLEEP_FOREVER, ADC_OFF, BOD_OFF);
	}

	// loop is started once the device wakes up again
	void loop() {
	blinkLED();
	delay(1000);
	}

	void blinkLED() {
	if (ledState == LOW) {
	ledState = HIGH;
	} else {
	ledState = LOW;
	}
	digitalWrite(LED_BUILTIN, ledState);
	}

	void wakeUp() {
	// wake up again
	Serial.println("Woke up this morning...");
	}