How to Use EM-18 RFID READER MODULE: Examples, Pinouts, and Specs

Introduction

The EM-18 RFID Reader Module is a compact and efficient device designed for reading RFID tags. Operating at a frequency of 125 kHz, it can detect and read RFID tags from a distance of up to 10 cm. The module outputs the tag data in a serial format, making it highly compatible with microcontrollers, such as Arduino, and other digital systems.

Explore Projects Built with EM-18 RFID READER MODULE

Use Cirkit Designer to design, explore, and prototype these projects online. Some projects support real-time simulation. Click "Open Project" to start designing instantly!

Biometric Access Control System with RFID and Touch Activation

This circuit is designed for security and identification purposes, featuring an RFID-RC522 module for contactless communication and a fingerprint scanner for biometric authentication. It includes an LCD display for user interaction, a touch sensor for input, a buzzer for audio feedback, and a relay module for controlling external devices. The components are interfaced with a NANO Expansion board, which likely contains a microcontroller to coordinate the operations of the system.

Open Project in Cirkit Designer

Arduino and ESP8266 RFID Door Lock System with WiFi Connectivity

This circuit features an Arduino UNO connected to an RFID-RC522 module for RFID scanning and an ESP8266 ESP-12E WiFi module for wireless communication. The Arduino controls a KY-019 Relay module, which in turn drives a 12V solenoid lock, allowing the lock to be actuated based on RFID card detection or potentially remote commands via WiFi. The Arduino's embedded code is set up to initialize the RFID reader and output the UID of scanned cards to the serial monitor.

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Arduino and ESP8266 RFID Access Control System with Servo Gate Operation

This circuit is designed for an RFID-based access control system using two Arduino UNO microcontrollers, each connected to an EM-18 RFID reader module, a servo motor, a buzzer, and two LEDs (one red and one green). The system reads RFID tags, checks for authorization, and controls gate access by actuating the servo motors. Visual (LED) and auditory (buzzer) indicators provide feedback on access granted or denied status.

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Arduino UNO Based RFID Access Control System with Servo Gate Operation

This circuit consists of two Arduino UNO microcontrollers, each connected to an EM-18 RFID reader module, a servo motor, a buzzer, and two LEDs (one red and one green). The Arduinos are programmed to read RFID tags, control access by actuating the servo motors as gates, and provide visual and auditory feedback using LEDs and buzzers. The system is designed to manage entry and exit access, likely for a secure area, by validating RFID tags against a list of authorized tags and recording entry/exit times.

Open Project in Cirkit Designer

Common Applications

• Access control systems (e.g., door locks, attendance systems)
• Inventory management and tracking
• Payment systems
• Security and authentication systems
• Embedded systems requiring RFID functionality

Technical Specifications

Below are the key technical details and pin configuration for the EM-18 RFID Reader Module:

Key Technical Details

Pin Configuration and Descriptions

The EM-18 module has a total of 7 pins. The table below describes each pin:

Usage Instructions

How to Use the EM-18 RFID Reader Module in a Circuit

1. Power the Module: Connect the VCC pin to a 5V DC power source and the GND pin to ground.
2. Connect to a Microcontroller:
   • Connect the TX pin of the EM-18 to the RX pin of the microcontroller (e.g., Arduino UNO).
   • Ensure the microcontroller's UART baud rate is set to 9600 bps to match the module's output.
3. Read RFID Tags:
   • When an RFID tag is brought within the module's range (up to 10 cm), the module reads the tag's unique ID.
   • The ID is transmitted via the TX pin in a serial format.
4. Optional Connections:
   • Use the BEEP pin to control an external buzzer for audible feedback.
   • Use the LED pin to control an external LED for visual feedback.

Important Considerations and Best Practices

• Power Supply: Ensure a stable 5V DC power supply to avoid erratic behavior.
• Tag Compatibility: Use only 125 kHz passive RFID tags for proper operation.
• Interference: Avoid placing the module near metal objects or other electronic devices that may cause interference.
• Antenna Range: Ensure the RFID tag is within the specified range (up to 10 cm) for reliable reading.

Example: Connecting EM-18 to Arduino UNO

Below is an example of how to connect and use the EM-18 RFID Reader Module with an Arduino UNO:

Circuit Connections

Arduino Code

// EM-18 RFID Reader Module Example with Arduino UNO
// Connect EM-18 TX pin to Arduino D2 (SoftwareSerial RX)

#include <SoftwareSerial.h>

// Define SoftwareSerial pins for EM-18
SoftwareSerial RFID(2, 3); // RX = Pin 2, TX = Pin 3 (TX not used here)

void setup() {
  Serial.begin(9600);       // Initialize Serial Monitor at 9600 bps
  RFID.begin(9600);         // Initialize SoftwareSerial for EM-18 at 9600 bps
  Serial.println("EM-18 RFID Reader Ready");
}

void loop() {
  if (RFID.available()) {   // Check if data is available from EM-18
    String tagData = "";    // Variable to store RFID tag data
    while (RFID.available()) {
      char c = RFID.read(); // Read each character from EM-18
      tagData += c;         // Append character to tagData
    }
    Serial.print("RFID Tag ID: ");
    Serial.println(tagData); // Print the tag ID to Serial Monitor
  }
}

Notes:

• Ensure the RFID tag is within range when testing.
• Use the Serial Monitor (set to 9600 baud) to view the tag ID.

Troubleshooting and FAQs

Common Issues and Solutions

FAQs

1. Can the EM-18 read multiple tags simultaneously?

   • No, the EM-18 can only read one tag at a time.

2. What is the maximum range of the EM-18?

   • The maximum range is approximately 10 cm, depending on the tag and environmental conditions.

3. Can I use the EM-18 with a 3.3V microcontroller?

   • Yes, but you will need a level shifter to safely interface the 5V TX output with the 3.3V RX input of the microcontroller.

4. Does the module support 13.56 MHz RFID tags?

   • No, the EM-18 only supports 125 kHz passive RFID tags.

By following this documentation, you can effectively integrate the EM-18 RFID Reader Module into your projects for reliable RFID tag reading.