// Uses a PIR sensor to detect movement, buzzes a buzzer // more info here: http://blog.makezine.com/projects/pir-sensor-arduino-alarm/ // email me, John Park, at jp@jpixl.net // based upon: // PIR sensor tester by Limor Fried of Adafruit // tone code by michael@thegrebs.com int ledPin = 13; // choose the pin for the LED int inputPin = 3; // choose the input pin (for PIR sensor) int pirState = LOW; // we start, assuming no motion detected int val = 0; // variable for reading the pin status int pinSpeaker = 10; //Set up a speaker on a PWM pin (digital 9, 10, or 11) void setup() { pinMode(ledPin, OUTPUT); // declare LED as output pinMode(inputPin, INPUT); // declare sensor as input pinMode(pinSpeaker, OUTPUT); Serial.begin(9600); } void loop(){ val = digitalRead(inputPin); // read input value if (val == HIGH) { // check if the input is HIGH digitalWrite(ledPin, HIGH); // turn LED ON playTone(300, 160); delay(150); if (pirState == LOW) { // we have just turned on Serial.println("Motion detected!"); // We only want to print on the output change, not state pirState = HIGH; } } else { digitalWrite(ledPin, LOW); // turn LED OFF playTone(0, 0); delay(300); if (pirState == HIGH){ // we have just turned of Serial.println("Motion ended!"); // We only want to print on the output change, not state pirState = LOW; } } } // duration in mSecs, frequency in hertz void playTone(long duration, int freq) { duration *= 1000; int period = (1.0 / freq) * 1000000; long elapsed_time = 0; while (elapsed_time < duration) { digitalWrite(pinSpeaker,HIGH); delayMicroseconds(period / 2); digitalWrite(pinSpeaker, LOW); delayMicroseconds(period / 2); elapsed_time += (period); } }