Arduino Alarm System with Motion Detection Using E18-D80NK

This guide walks through building a complete Arduino alarm system using E18-D80NK infrared sensor, buzzer, two ISD1820 voice modules, a 315MHz RF remote, and a 1602 LCD display. The system can be armed or disarmed remotely and provides both audio and visual feedback.

Components Needed

Component	Quantity
Arduino UNO R3	1
E18-D80NK Object Detection Sensor	1
Active Buzzer	1
ISD1820 Voice Recording/Playback Module	2
M4 RF Remote Module 315MHz	1 set
LCD 1602 with I2C Adapter	1
Jumper wires various colors	-

Wiring Diagram

E18-D80NK Object Detection Sensor

• Brown wire (5V) → Arduino 5V
• Blue wire (GND) → Arduino GND
• Black wire (Data) → Arduino Pin 2

Active Buzzer

• VCC → 5V
• GND → GND
• I/O → Pin 3

ISD1820 Module #1 (System OFF sound)

• VCC → 5V
• GND → GND
• PLAYE → Pin 4

ISD1820 Module #2 (System ON sound)

• VCC → 5V
• GND → GND
• PLAYE → Pin 5

M4 RF Remote Module 315MHz

• VCC → 5V
• GND → GND
• D0 → Pin 8
• D2 → Pin 9

LCD 1602 (I2C)

• VCC → 5V
• GND → GND
• SDA → A4
• SCL → A5

Pre-Setup Steps

1. Set Remote Address by Soldering

Solder the pins at positions H-8-4 on the M4 RF module to create a unique address code. This prevents signal interference with other remotes in the same area.

2. Record Audio on ISD1820 Modules

• Hold the REC button while speaking (max 10 seconds)
• Record “System OFF” on Module #1
• Record “System ON” on Module #2
• Press PLAY to verify recordings

Note: PLAYE button plays once to completion. PLAYL button plays only while held down.

3. Install LCD I2C Library

Download the LiquidCrystal_I2C library and place it in your Arduino IDE libraries folder (Documents/Arduino/libraries)

Arduino Code for Alarm System

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Pin definitions
#define SENSOR_PIN 2
#define BUZZER_PIN 3
#define PLAYE1_PIN 4
#define PLAYE2_PIN 5
#define REMOTE_D0 8
#define REMOTE_D2 9

// System state
bool systemActive = false;

// Initialize LCD (common address 0x27)
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  Serial.begin(9600);
  
  // Configure pins
  pinMode(SENSOR_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(PLAYE1_PIN, OUTPUT);
  pinMode(PLAYE2_PIN, OUTPUT);
  pinMode(REMOTE_D0, INPUT);
  pinMode(REMOTE_D2, INPUT);
  
  // Initialize outputs to LOW
  digitalWrite(PLAYE1_PIN, LOW);
  digitalWrite(PLAYE2_PIN, LOW);
  digitalWrite(BUZZER_PIN, LOW);
  
  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("System Ready  ");
  lcd.setCursor(0, 1);
  lcd.print("Press B to ON ");
  
  Serial.println("Alarm System Ready");
}

void loop() {
  int remoteA = digitalRead(REMOTE_D0);  // Button A - Disarm
  int remoteB = digitalRead(REMOTE_D2); // Button B - Arm
  int sensorStatus = digitalRead(SENSOR_PIN);
  
  // Debounce remote buttons
  static bool lastRemoteA = LOW;
  static bool lastRemoteB = LOW;
  
  if (remoteA == HIGH && lastRemoteA == LOW) {
    // Disarm system
    systemActive = false;
    digitalWrite(BUZZER_PIN, LOW);
    digitalWrite(PLAYE1_PIN, HIGH);
    delay(500);
    digitalWrite(PLAYE1_PIN, LOW);
    updateDisplay("SYSTEM OFF", "Press B to ON ");
    Serial.println("System OFF - Alarm deactivated");
  }
  
  if (remoteB == HIGH && lastRemoteB == LOW) {
    // Arm system
    systemActive = true;
    digitalWrite(PLAYE2_PIN, HIGH);
    delay(500);
    digitalWrite(PLAYE2_PIN, LOW);
    updateDisplay("SYSTEM ON ", "Monitoring...");
    Serial.println("System ON - Alarm activated");
  }
  
  lastRemoteA = remoteA;
  lastRemoteB = remoteB;
  
  // Detect motion when armed
  if (systemActive) {
    if (sensorStatus == 1) {
      digitalWrite(BUZZER_PIN, HIGH);
      lcd.setCursor(0, 1);
      lcd.print("ALERT!Motion!");
      Serial.print("Sensor: ");
      Serial.println(sensorStatus);
    } else {
      digitalWrite(BUZZER_PIN, LOW);
      lcd.setCursor(0, 1);
      lcd.print("Monitoring... ");
    }
  }
  
  delay(50);
}

void updateDisplay(String line1, String line2) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(line1);
  lcd.setCursor(0, 1);
  lcd.print(line2);
}

Adjustment needed: LCD I2C address may be 0x3F instead of 0x27 depending on your module. Verify with an I2C Scanner sketch first.

Upload and Testing Steps

1. Open Arduino IDE and paste the code above
2. Select Board: Arduino UNO and the correct Port
3. Click Upload and wait for “Done uploading”
4. Open Serial Monitor and set baud rate to 9600

Test Arming

Press button B on remote → LCD shows “SYSTEM ON” → ISD1820 Module #2 plays “System ON” audio

Test Motion Detection

Walk toward E18-D80NK → Buzzer sounds → Serial Monitor shows value change from 0 to 1

Test Disarming

Press button A on remote → LCD shows “SYSTEM OFF” → ISD1820 Module #1 plays “System OFF” audio → Sensor stops sending signals to board

Adjusting Detection Range

Rotate the adjustment potentiometer on the E18-D80NK to change detection range (3-80 cm). Adjust the potentiometer on the RF module to change wireless reception range.

Summary

This alarm system consists of 4 main parts: object detection sensor → alert unit (buzzer) → status notification (LCD + audio) → control unit (remote). The system provides dual feedback through both LCD screen and Serial Monitor, with adjustable detection parameters to suit different environments.