powerDownWakeupExternalClockInterruptSwitch.ino

// **** INCLUDES *****
#include "LowPower.h"
#include <DS3232RTC.h>        //http://github.com/JChristensen/DS3232RTC
#include <Wire.h>             //http://arduino.cc/en/Reference/Wire


// Use pin 2 as wake up pin
const int wakeUpPin = 2;

int led = 9;
int nMos = 3;

int sleepInterval = 10;
int onInterval = 5;

volatile boolean alarmIsrWasCalled = false;

void wakeUp()
{
    // Just a handler for the pin interrupt.
    alarmIsrWasCalled = true;
}

void setup()
{

     pinMode(nMos,OUTPUT);
     digitalWrite(nMos,LOW);


    // Configure wake up pin as input.
    // This will consumes few uA of current.
    pinMode(wakeUpPin, INPUT_PULLUP);  

    // pin 5 is the RTC pin -- add an internal pullup
    pinMode(5,INPUT_PULLUP);

    //Serial.begin(115200);


    
    //Disable the default square wave of the SQW pin.
    RTC.squareWave(SQWAVE_NONE);

    
    //int seconds = second(RTC.get());
    //int alarmSeconds = (seconds+10)%60;

    int alarmSeconds=20;
    
    RTC.setAlarm(ALM1_MATCH_SECONDS, alarmSeconds, 0, 0, 1);    //daydate parameter should be between 1 and 7
    RTC.alarm(ALARM_1);                   //ensure RTC interrupt flag is cleared
    RTC.alarmInterrupt(ALARM_1, true);

}

void loop() 
{

  //Disable the default square wave of the SQW pin.
    RTC.squareWave(SQWAVE_NONE);
   
    //int seconds = second(RTC.get());
    //int alarmSeconds = (seconds+10)%60;

    //every interval seconds
    
    int alarmSeconds=(second(RTC.get())+sleepInterval)%60;
    RTC.setAlarm(ALM1_MATCH_SECONDS, alarmSeconds, 0, 0, 1);    //daydate parameter should be between 1 and 7
    RTC.alarm(ALARM_1);                   //ensure RTC interrupt flag is cleared
    RTC.alarmInterrupt(ALARM_1, true);
    

    //every interval minutes
    /*
    int alarmMinutes=(minute(RTC.get())+interval)%60;
    RTC.setAlarm(ALM1_MATCH_MINUTES, 0, alarmMinutes, 0, 1);    //daydate parameter should be between 1 and 7
    RTC.alarm(ALARM_1);                   //ensure RTC interrupt flag is cleared
    RTC.alarmInterrupt(ALARM_1, true);
    */

    
    // Allow wake up pin to trigger interrupt on low.
    attachInterrupt(0, wakeUp, LOW);

    Serial.print("Sleeping for ");
    Serial.println(sleepInterval);
    delay(20);
    // Enter power down state with ADC and BOD module disabled.
    // Wake up when wake up pin is low.
    LowPower.powerDown(SLEEP_FOREVER, ADC_OFF, BOD_OFF); 

    delay(20);

    Serial.print("Waking up for ");
    Serial.println(onInterval); 
    // Disable external pin interrupt on wake up pin.
    detachInterrupt(0); 



  pinMode(led, OUTPUT);
    for (int i=0;i<3;i++) {
    digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(30);              // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(30);
    }

    // turn on the switch
   digitalWrite(nMos,HIGH);

   // keep it on onInterval 
   delay(onInterval*1000); // amount of time to keep the switch on 

     pinMode(led, OUTPUT);
    for (int i=0;i<3;i++) {
    digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(30);              // wait for a second
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(30);
    }
    
   

// turn off the switch
   digitalWrite(nMos,LOW);

    // Do something here
    // Example: Read sensor, data logging, data transmission.
}

requires: https://github.com/JChristensen/DS3232RTC and https://github.com/rocketscream/Low-Power