📘 Home Security System ( Blynk IoT Cloud Version )

🎯 Objective of This Lesson

Students will learn:

• What is Cloud-Based Security Monitoring

• How ESP32 connects to Blynk Cloud

• How to create Datastreams

• How to design Dashboard

• How to monitor motion from anywhere

🌐 What is Blynk IoT?

Blynk is a cloud IoT platform that allows:

• Remote device monitoring

• Real-time alerts

• Mobile dashboard control

• Internet-based communication

ESP32 sends motion data to Blynk Cloud.
Mobile app receives it from anywhere.

🧾 Step 1 – Create Blynk Template

1️⃣ Go to: https://blynk.cloud
2️⃣ Login / Sign up
3️⃣ Click Create Template
4️⃣ Choose:

• Hardware → ESP32

• Connection Type → WiFi

5️⃣ Save Template

🧾 Step 2 – Create Datastreams

Go to:

Template → Datastreams → New Datastream

Create the following:

Save all.

🧾 Step 3 – Create Device

1️⃣ Go to Devices
2️⃣ Click New Device
3️⃣ From Template
4️⃣ Copy:

• Template ID

• Template Name

• Auth Token

You will paste these into the code.

🧾 Step 4 – Dashboard Setup

Open Web Dashboard or Mobile App.

Add Widgets:

1️⃣ Label → V0 → Motion Status
2️⃣ LED Widget → V1 → Motion State

Configure LED:

• 1 → ON

• 0 → OFF

Dashboard is now ready.

🔌 Hardware Reminder

🧾 Complete ESP32 Blynk Code (Copy–Paste Ready)

⚠ Replace WiFi & Blynk credentials before uploading.

#define BLYNK_TEMPLATE_ID "YOUR_TEMPLATE_ID"
#define BLYNK_TEMPLATE_NAME "HomeSecurity"
#define BLYNK_AUTH_TOKEN "YOUR_AUTH_TOKEN"

#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

#define PIR_PIN 27

char ssid[] = "YOUR_WIFI_NAME";
char pass[] = "YOUR_WIFI_PASSWORD";

BlynkTimer timer;

int motionState = 0;
int lastState = 0;

void sendMotionData() {

motionState = digitalRead(PIR_PIN);

if (motionState == HIGH) {
Blynk.virtualWrite(V0, "⚠ MOTION DETECTED!");
Blynk.virtualWrite(V1, 1);
} else {
Blynk.virtualWrite(V0, "Area Secure");
Blynk.virtualWrite(V1, 0);
}
}

void setup() {

Serial.begin(115200);
pinMode(PIR_PIN, INPUT);

Serial.println("Connecting to Blynk...");
Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);

Serial.println("Warming up PIR Sensor...");
delay(30000);
Serial.println("System Ready!");

timer.setInterval(2000L, sendMotionData);
}

void loop() {

Blynk.run();
timer.run();
}

🧠 Code Explanation (Step-by-Step)

1️⃣ Blynk Credentials

These link ESP32 to your cloud project.

Without correct credentials → device will not connect.

2️⃣ Blynk.begin()

Connects ESP32 to:

• WiFi

• Blynk Cloud server

3️⃣ Reading PIR Sensor

Returns:

1 → Motion detected
0 → No motion

4️⃣ Sending Data to Cloud

Sends motion status text.

Turns ON LED widget.

5️⃣ Timer Usage

Runs motion check every 2 seconds.

Prevents blocking loop.

📊 Dashboard Example Output

When motion detected:

V0 → ⚠ MOTION DETECTED!
LED → ON

When no motion:

V0 → Area Secure
LED → OFF

🎓 Learning Outcomes

Students now understand:

• Cloud-based security monitoring

• Virtual Pins

• Real-time dashboard control

• IoT-based home automation

• Professional deployment structure

🔥 Optional Advanced Upgrade

You can extend this projet by adding:

• Blynk Notification when motion detected

• Email alert

• Event logging

• Camera integration

• Multi-room motion system