NFC Reader/Writer Application

A Node.js console application for reading and writing data to NFC cards.

Features

• 🔍 Automatic card detection - Detects when NFC cards are placed on the reader
• 📖 Read support - Read data from various NFC card types
• ✍️ Write support - Write custom text data to NFC cards
• 🎯 Interactive prompts - User-friendly command-line interface
• 🔄 Continuous operation - Keeps running and detects multiple cards
• 📋 Detailed card info - Shows UID, type, standard, and ATR

Supported Card Types

• MIFARE Ultralight (fully supported - automatic detection)
• MIFARE Classic (1K, 4K)
• MIFARE DESFire
• ISO-DEP cards
• Most ISO 14443-3 and ISO 14443-4 compatible cards
• NDEF formatted tags

Automatic Card Detection

The application automatically detects the card type by analyzing the ATR (Answer To Reset) and adjusts its behavior accordingly:

• MIFARE Ultralight: Uses 4-byte page addressing (pages 0-15+)
• MIFARE Classic: Uses 16-byte block addressing with sector authentication (blocks 0-63)
• Other cards: Attempts standard NDEF or ISO-DEP operations

Prerequisites

Windows

• Install PC/SC driver (usually pre-installed on Windows 10/11)
• NFC reader compatible with PC/SC (e.g., ACR122U, PN532)

macOS

• PC/SC driver is built-in
• NFC reader compatible with PC/SC

Linux

• Install pcscd package:

  sudo apt-get install pcscd pcsc-tools

• NFC reader compatible with PC/SC

Installation

1. Install dependencies:

npm install

2. Connect your NFC reader to your computer

3. Run the application:

npm start

Usage

1. Run the application with npm start

2. Place an NFC card on the reader

3. Choose from the menu:

   • Read - Displays all readable data from the card
   • Write - Prompts for text input and writes it to the card
   • Skip - Ignores the current card

4. Remove the card when done

5. Place another card to continue, or press Ctrl+C to exit

Writing Data

When writing data:

1. Select "Write" from the menu
2. Enter the text you want to write
3. Confirm the operation
4. The data will be written starting from block 4 (to preserve system blocks)
5. The application will verify the write operation

Note:

• Writing requires authentication (uses default key: FF FF FF FF FF FF)
• Some cards may be write-protected
• System blocks (0-3) are preserved to avoid damaging the card

Reading Data

The application attempts to read data using different methods based on card type:

• MIFARE Classic: Reads all 64 blocks (1K cards) with authentication
• ISO-DEP cards: Attempts to read NDEF application data
• Other cards: Reads common NDEF data locations

All readable data is displayed in both hexadecimal and ASCII format.

Troubleshooting

"No NFC reader connected" error

• Ensure your NFC reader is properly connected
• Check that drivers are installed (PC/SC)
• Try unplugging and reconnecting the reader

"Authentication failed" when reading/writing

• The card may use different keys than the default
• Try different MIFARE keys or consult card documentation

Card not detected

• Ensure the card is properly placed on the reader
• Some readers require the card to be centered
• Try removing and replacing the card

Security Note

This application uses default MIFARE keys (FF FF FF FF FF FF). For production use with sensitive data, you should:

• Use custom keys for authentication
• Implement proper key management
• Add encryption for sensitive data
• Follow security best practices for your specific use case

License

MIT

README.md written by GitHub Copilot