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@efatsi efatsi/main.ino Secret
Last active Jan 3, 2018

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PIR detection library for Arduino
#include "pir.h"
Pir pir;
void setup() {}
void loop() {
pir.update();
if (pir.movementOn) {
Serial.println("Movement detected!");
}
if (pir.movementOff) {
Serial.println("Movement stopped.");
}
}
#include "pir.h"
Pir::Pir() {
pinMode(PIR_PIN, INPUT);
_resetInterval();
// give the sensor a couple seconds to wake up
_intervalStart = millis() + 5000;
}
void Pir::update() {
_resetMovementVariables();
_makeReading();
if (millis() > _intervalStart + READING_INTERVAL) {
_analyzeInterval();
_resetInterval();
}
}
void Pir::_resetMovementVariables() {
movementOn = false;
movementOff = false;
}
void Pir::_makeReading() {
int pirReading = analogRead(PIR_PIN);
if (pirReading < _pirLow) _pirLow = pirReading;
if (pirReading > _pirHigh) _pirHigh = pirReading;
}
void Pir::_analyzeInterval() {
int difference = _pirHigh - _pirLow;
if (!_seesMovement) {
if (difference > MOVEMENT_THRESHOLD) {
movementOn = true;
_seesMovement = true;
_lastSustainingMeasurement = millis();
}
} else {
if (difference > SUSTAIN_THRESHOLD) {
_lastSustainingMeasurement = millis();
} else {
if (millis() > _lastSustainingMeasurement + SUSTAIN_BUFFER) {
movementOff = true;
_seesMovement = false;
}
}
}
}
void Pir::_resetInterval() {
_pirLow = 4096;
_pirHigh = 0;
_intervalStart = millis();
}
#ifndef Pir_h
#define Pir_h
#include "application.h"
#define PIR_PIN A0
#define READING_INTERVAL 250
#define SUSTAIN_BUFFER 750
#define MOVEMENT_THRESHOLD 2500
#define SUSTAIN_THRESHOLD 1000
class Pir {
public:
Pir();
void update();
bool movementOn = false;
bool movementOff = false;
private:
void _resetMovementVariables();
void _makeReading();
void _analyzeInterval();
void _resetInterval();
long _intervalStart;
long _lastSustainingMeasurement;
int _pirLow;
int _pirHigh;
bool _seesMovement = false;
};
#endif
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