How to connect an NFC reader to Arduino

Contents

  1. Introduction
  2. Specification
  3. Wiring
  4. Code Example
  5. Dig deeper
  6. References

Introduction

Near field communication (NFC) is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity, usually no more than a few centimeters.
With this inexpensive and easy to use device you can bear any kind of information you wish to use stored even a keyring or a card.

Specification

  • Gilt PCB
  • Work in NFC Mode or RFID reader/writer Mode
  • RFID reader/writer supports:
  • Mifare 1k, 4k, Ultralight, and DesFire cards
  • ISO/IEC 14443-4 cards such as CD97BX, CD light, Desfire, P5CN072 (SMX)
  • Innovision Jewel cards such as IRT5001 card
  • FeliCa cards such as RCS_860 and RCS_854
  • Plug and play, Arduino compatible
  • Built in PCB Antenna, with 4cm~6cm communication distance
  • On-board level shifter, Standard 5V TTL for I2C and UART, 3.3V TTL SPI
  • Work as 1443-A card or a virtual card
  • Exchange data with other NFC devices such as smartphone
  • Weight: 0.0625 lbs
  • Dimensions: 4.5 x 3 x .125 inch
  • The PN532 board with integrated NFC loop antenna
  • 4 jumper wires, 6 inches (15cm) long
  • A 4 pin and an 8 pin angled header
  • An on-board level shifter for 3.3v SPI and 5v I2C & Uar

nfc module
Figure 1 - NFC module

Wiring

You can use your NFC shield by attaching a sensor shield to your Arduino board.

nfc reader connected to arduino with a sensor shield
Figure 2 - NFC reader connected to Arduino with a sensor shield

If you wish to connect the device directly to the Arduino board you have to follow the following pin assignment:

Arduino PN532 Module
GND GND
5V VCC
A4 SDA SDA
A5 SCL SCL

Code Example

  1. Download zip file: PN532 NFC Arduino example.zip
  2. Extract the three folders(PN532, PN532_SPI, PN532_HSU and PN532_I2C) into libraries of Arduino.
  3. Follow the examples of the PN532 library

RDFI Reader / Writer function

/** include library */ 
#include "Wire.h" 
#include "nfc.h" 
/** define an nfc object 
*/
NFC_Module nfc; 
void setup(void) 
{ 
Serial.begin(9600); 
nfc.begin(); 
Serial.println("MF1S50 Reader Demo From Elechouse!"); 
uint32_t versiondata = nfc.get_version(); 
if (! versiondata) { 
Serial.print("Didn't find PN53x board"); 
while (1); // halt 
} 
// Got ok data, print it out! 
Serial.print("Found chip PN5"); 
Serial.println((versiondata>>24) & 0xFF, HEX); 
Serial.print("Firmware ver. "); 
Serial.print((versiondata>>16) & 0xFF, DEC); 
Serial.print('.'); 
Serial.println((versiondata>>8) & 0xFF, DEC); 
/** Set normal mode, and disable SAM */ 
nfc.SAMConfiguration(); 
} 
void loop(void) 
{ 
u8 buf[32],sta; 
/** Polling the mifar card, buf[0] is the length of the UID */ 
sta = nfc.InListPassiveTarget(buf); 
/** check state and UID length */
if(sta && buf[0] == 4){ 
/** the card may be Mifare Classic card, try to read the block */ 
Serial.print("UUID length:"); 
Serial.print(buf[0], DEC); 
Serial.println(); 
Serial.print("UUID:"); 
nfc.puthex(buf+1, buf[0]); 
// print out the UID 
Serial.println(); 
/** factory default KeyA: 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF */
u8 key[6] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}; 
u8 blocknum = 4; 
/** Authentication block 4 */ 
sta = nfc.MifareAuthentication(0, blocknum, buf+1, buf[0], key); 
if(sta){ 
/** create array to save block data read from the card
*/
u8 block[16]; 
Serial.println("Authentication success."); 
/*********************************************************** 
The following are examples to write data to RFID card. To 
protect user
’
s data in RFID card. By Default we disabled it. 
Please remove the annotation symbol to enable it 
***********************************************************/ 
/* 
strcpy((char*)block, "Elechou
se
- NFC"); 
sta = nfc.MifareWriteBlock(blocknum, block); 
if(sta){ 
Serial.println("Write block successfully:"); 
} 
*/ 
/*********************************************************** 
The following are examples to read data from RFID card. 
***********************************************************/
/** read block 4 */ 
sta = nfc.MifareReadBlock(blocknum, block); 
if(sta){ 
Serial.println("Read block successfully:"); 
nfc.puthex(block, 16); 
Serial.println(); 
} 
/** read block 5 */
sta = nfc.MifareReadBlock(blocknum+1, block); 
if(sta){ 
Serial.println("Read block successfully:"); 
nfc.puthex(block, 16); 
Serial.println(); 
} 
/** read block 6 */ 
sta = nfc.MifareReadBlock(blocknum+2, block); 
if(sta){ 
Serial.println("Read block successfully:"); 
nfc.puthex(block, 16); 
Serial.println(); 
} 
/** read block 7 */ 
sta = nfc.MifareReadBlock(blocknum+3, block); 
if(sta){ 
Serial.println("Read block successfully:"); 
nfc.puthex(block, 16); 
Serial.println(); 
} 
} 
} 
}
  • Upload the code to Arduino, and then open the Serial Monitor on Arduino IDE
  • Put the card above the antenna.
  • You are uploaded the data to your card.


Or you can use a premade example.

  1. Open the iso14443a_uid example in the Arduino IDE.

    arduino programming example
    Figure 3 - Open the example

  2. Modify the code

    programming arduino
    Figure 4 - How to change the code

  3. Upload the code to Arduino and open Serial monitor. Put a card on it.

    nfc card
    Figure 4 - Send the data to the card

Dig deeper

If you are looking for detailed information read the PN532 NFC's user guide: PN532 NFC User Guide.pdf

References

More information