source: de.wigbels.avr/sketchbook/hothotheat/hothotheat.pde@ b51b715

/*
 * HotHotHeat
 *
 * Compile with the Arduino IDE (http://arduino.cc); is deployed against a 
 * Atmel Butterfly - so you also need the Butteruino project
 * (http://code.google.com/p/butteruino/)
 *
 * ...will
 * 1) Read the Butterfly temperature sensor and output
 * the result permanently to UART.
 *
 * 2) Read a reed sensor and output
 * the result permanently to UART
 *
 * Contact: Norbert Wigbels
 * (http://foobla.wigbels.de/uber-foobla/)
 *
 * Format: <# of Sensor> <data>
 * Example: 1; Temperature in Celsius
 * tbd.
 */
 
#include <butterfly_temp.h>
#include <pins_butterfly.h>

#include <LCD_Driver.h>
#include <timer2_RTC.h>


int inputReed = PBPIN4;
int outputLED = PBPIN3;

int value = 0;
int debounce = 0;

long gasReeds = 0;

void setup() {
  LCD.prints_f(PSTR("HOTHOTHEAT"));
  delay(2500);
 
  // Set up the RTC timer to call the secTick() function every second.
  RTCTimer.init( secTick );
  
  Serial.begin(9600); 

  TempSense.overSample = true;

  pinMode(inputReed, INPUT);
  pinMode(outputLED, OUTPUT);
}

void secTick()
{
  LCD.print( gasReeds );
  LCD.println( " tGR" );
}

int getSamples() {
  // Temperature = Sensor 1
  Serial.print("1");
  Serial.print("\t");
  Serial.println(TempSense.getTemp(CELSIUS));

  // switchtime of reed is 18 ms including debouncing...
  value = digitalRead(inputReed);
  delay(20);
  debounce = digitalRead(inputReed);

  // Reedcontact = Sensor 2
  if (value==debounce) {
    Serial.print("2");
    Serial.print("\t");
    if (value == HIGH) {
      Serial.println("HIGH");
      gasReeds++;
      return 1;
    }
    else {
      Serial.println("LOW");
      return 0;
    }
  }
}

void loop() {  
  // Switch LED on for a certain time to mark a switched Reed contact
  if(getSamples()==1) {
    digitalWrite(outputLED, HIGH);
  } else {
    digitalWrite(outputLED, LOW);
  }

  delay(100);
}