Last active
April 27, 2017 16:03
-
-
Save AnowarCST/b35a08dcfffcedc54326f9e2cf7b4d63 to your computer and use it in GitHub Desktop.
PIR Motion Sensor with Arduino
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
//the time we give the sensor to calibrate (10-60 secs according to the datasheet) | |
int calibrationTime = 30; | |
//the time when the sensor outputs a low impulse | |
long unsigned int lowIn; | |
//the amount of milliseconds the sensor has to be low | |
//before we assume all motion has stopped | |
long unsigned int pause = 5000; | |
boolean lockLow = true; | |
boolean takeLowTime; | |
int pirPin = 3; //the digital pin connected to the PIR sensor's output | |
int ledPin = 13; | |
///////////////////////////// | |
//SETUP | |
void setup(){ | |
Serial.begin(9600); | |
pinMode(pirPin, INPUT); | |
pinMode(ledPin, OUTPUT); | |
digitalWrite(pirPin, LOW); | |
//give the sensor some time to calibrate | |
Serial.print("calibrating sensor "); | |
for(int i = 0; i < calibrationTime; i++){ | |
Serial.print("."); | |
delay(1000); | |
} | |
Serial.println(" done"); | |
Serial.println("SENSOR ACTIVE"); | |
delay(50); | |
} | |
//////////////////////////// | |
//LOOP | |
void loop(){ | |
if(digitalRead(pirPin) == HIGH){ | |
digitalWrite(ledPin, HIGH); //the led visualizes the sensors output pin state | |
if(lockLow){ | |
//makes sure we wait for a transition to LOW before any further output is made: | |
lockLow = false; | |
Serial.println("---"); | |
Serial.print("motion detected at "); | |
Serial.print(millis()/1000); | |
Serial.println(" sec"); | |
delay(50); | |
} | |
takeLowTime = true; | |
} | |
if(digitalRead(pirPin) == LOW){ | |
digitalWrite(ledPin, LOW); //the led visualizes the sensors output pin state | |
if(takeLowTime){ | |
lowIn = millis(); //save the time of the transition from high to LOW | |
takeLowTime = false; //make sure this is only done at the start of a LOW phase | |
} | |
//if the sensor is low for more than the given pause, | |
//we assume that no more motion is going to happen | |
if(!lockLow && millis() - lowIn > pause){ | |
//makes sure this block of code is only executed again after | |
//a new motion sequence has been detected | |
lockLow = true; | |
Serial.print("motion ended at "); //output | |
Serial.print((millis() - pause)/1000); | |
Serial.println(" sec"); | |
delay(50); | |
} | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
http://www.circuitmagic.com/arduino/pir-motion-sensor-with-arduino/