Arduino Nano + PIR Motion sensor

Parts list

- Arduino Nano
- PIR Motion sensor
- Jumper wires
- Resistor 220 ohm

Schematic diagram

Arduino Sketch

int ledPin = 2; // choose the pin for the LED
int inputPin = 9; // 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

void setup() {
  // put your setup code here, to run once:
  pinMode(ledPin, OUTPUT); // declare LED as output
  pinMode(inputPin, INPUT); // declare sensor as input


void loop() {
  val = digitalRead(inputPin); // read input value
if (val == HIGH) { // check if the input is HIGH
  digitalWrite(ledPin, HIGH); // turn LED ON
  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
  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;



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