dormir.c

#include <avr/sleep.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>

#define RAIN_GAUGE_PIN 2

const byte LED = 13;
volatile unsigned long last_rain_IRQ  = 0; /* Debouncing */
volatile unsigned int rain_clicks     = 0;

ISR(INT0_vect)
{
  if (millis() - last_rain_IRQ > 10) {
    last_rain_IRQ = millis();
    rain_clicks++;
    Serial.println("haha");
  }
}


float get_rainfall()
{
  float rainfall = (rain_clicks * 0.1);
  rain_clicks = 0; /* Reseta a quantidade de chuva após cada consulta */
  return rainfall;
}

void flash ()
{
  pinMode (LED, OUTPUT);
  for (byte i = 0; i < 10; i++)
  {
    digitalWrite (LED, HIGH);
    delay (500);
    digitalWrite (LED, LOW);
    delay (500);
  }

  pinMode (LED, INPUT);

}  // end of flash

// watchdog interrupt
ISR (WDT_vect)
{
  wdt_disable();  // disable watchdog
}  // end of WDT_vect

void setup () {
  Serial.begin(9600);
  pinMode(2, INPUT);
  digitalWrite (2, HIGH);
  
  EICRA = (0 << ISC00) | (0 << ISC01) | (0 << ISC10) | (0 << ISC11) ; //INT0 e INT1 no nível zero.
  EIMSK = (0 << INT1) | (1 << INT0); //habilita INT0 
  sei(); //habilita interrupções globais, ativando o bit I do SREG

  /** Interrupção do pluviômetro */
  //pinMode(RAIN_GAUGE_PIN, INPUT);
  //digitalWrite(RAIN_GAUGE_PIN, HIGH);
  //attachInterrupt(0, rain_IRQ, FALLING);
}

void loop ()
{

  flash ();

  // disable ADC
  ADCSRA = 0;

  // clear various "reset" flags
  MCUSR = 0;
  // allow changes, disable reset
  WDTCSR = bit (WDCE) | bit (WDE);
  // set interrupt mode and an interval
  WDTCSR = bit (WDIE) | bit (WDP3) | bit (WDP0);    // set WDIE, and 8 seconds delay
  wdt_reset();  // pat the dog

  set_sleep_mode (SLEEP_MODE_PWR_DOWN);
  noInterrupts ();           // timed sequence follows
  sleep_enable();

  // turn off brown-out enable in software
  MCUCR = bit (BODS) | bit (BODSE);
  MCUCR = bit (BODS);
  interrupts ();             // guarantees next instruction executed
  sleep_cpu ();

  // cancel sleep as a precaution
  sleep_disable();
  Serial.println(get_rainfall());


} // end of loop