Last week , I decided to pick up an Arduino-based project — mainly because I missed dabbling in a project that was outside of my comfort zone. Plus, I hadn’t touched a bread-board or a soldering iron in years (6 years to be precise).

As all project ideas go, I turned to Pinterest 😅

Found a super-informative post by Angus Young (Gus), one of 2 maintainers of the PiMyLifeUp blog page. It gives you a really good starting point for an Arduino-virgin like me. I plan on doing my best to put into words, the steps I took, mistakes I made and what the end-product looked like!

Parts required:

• LED bulbs
• Jumper wires for the board
• 100 ohm resistors
• Piezo-buzzer (only get this if your partner doesn’t mind annoying sounds)
• Breadboard
• Adafruit PIR motion sensor
• Arduino (or Elegoo — the cheaper but functionally identical option) Uno R3 Board

Software required:

The only real software I needed was the Arduino IDE installed — this works for both the Arduino and Elegoo boards:

Code:

Here’s the code I used — a lot of it derived from Gus’ project I mentioned earlier.

Please ignore the pitches header being included — I was messing around with some melodies with the piezo-buzzer before my girlfriend walked by and unplugged it.

#include "pitches.h"

int ledPin = 4;
int piezoBuzzerPin = 3;
int pirSensorPin = 2;
int motionDetected = HIGH;
int blinkTime = 100;
int melody[] = {NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3, 0, NOTE_B3, NOTE_C4};

int noteDurations[] = {4, 8, 8, 4, 4, 4, 4, 4};

void setup() {
  pinMode(ledPin, OUTPUT);      // declare LED as output
  pinMode(pirSensorPin, INPUT);     // declare the PIR sensor as input
  pinMode(piezoBuzzerPin, OUTPUT); //declare buzzer as output
  Serial.begin(9600); //Set serial out if we want debugging
  delay(1000); //Allow time for the PIR Sensor to callibrate

    for (int thisNote = 0; thisNote < 8; thisNote++) {
      int noteDuration = 1000 / noteDurations[thisNote];
      tone(8, melody[thisNote], noteDuration);
      // the note's duration + 30% seems to work well:
      int pauseBetweenNotes = noteDuration * 1.30;
      delay(pauseBetweenNotes);
      noTone(8);
  }
}

int counter=0;
void blinkNow(int repeats, int time)
{
  for (int i = 0; i < repeats; i++)
  {
    digitalWrite(ledPin, HIGH);
    digitalWrite(piezoBuzzerPin, HIGH);
    delay(time);
    digitalWrite(ledPin, LOW);
    digitalWrite(piezoBuzzerPin, LOW);
    delay(time);
    int noteDuration = 1000 / noteDurations[0];
    tone(8, melody[0], noteDuration);
  }
}

void loop() {
  delay(3000); //Setting this delay to give the PIR sensor some time to reset
  motionDetected = digitalRead(pirSensorPin);
  digitalWrite(ledPin, LOW);
  digitalWrite(piezoBuzzerPin, LOW);
  if (motionDetected == HIGH)
  {
    counter+=1;
    Serial.print("Count = "); Serial.println(counter);
    blinkNow(1, blinkTime);
  }
}