13.56Mhz RFID module - IOS/IEC 14443 type a


  • Model No. RDM880-T-A
  • R/W chip MFRC500,MFRC400,MFRC531,MFRC632
  • Standard ISO/IEC 14443 type a
  • Frequency 13.56MHz
  • Baud Rate 9600-115200bit/s(configurable, default9600)
  • Power supply DC5V(5%)
  • Current <70mA
  • Operating range 30-100mm(reading range depend on antenna and card/tag)
  • interface TTL electrical level
  • Working temperature -10 degree to 70 degree
  • Storage temperature -20 degree to 80 degree
  • Size 39*19*9 mm(DIP28)

Links to external webpages which provide more application ideas, documents/datasheet or software libraries.

Connecting to an Arduino

The SeeedStudio 13.56Mhz RFID module is an RFID reader capable support ISO14443A, Mifare series card over a serial line. It can easely be attached to an arduino to have RFID fun.


       | [1][2]      [5][4][3][2][1] |
       |  J3              J1         |
       |           RDM880 (top view) |
       |                  J2         |
       |             [5][4][3][2][1] |
J1:(accessory pins)
  PIN 1 -- LEDG (Green led)
  PIN 2 -- 5V (DC)
  PIN 3 -- GND
  PIN 4 -- LEDR (Red led)
  PIN 5 -- BUZ (Buzzer)

J1 Alt: Note that some units are arranged:

  PIN 1 --
  PIN 2 --
  PIN 3 -- LED1 (Green led)
  PIN 4 -- LED2 (RED led)
  PIN 5 -- BUZ (Buzzer)
J2:(Communication using serial 9600 8N1 TTL level)
  PIN 1 -- RESET (pull low to reset e.g. set default baudrate)
  PIN 2 -- RX
  PIN 3 -- TX
  PIN 4 -- GND
  PIN 5 -- 5V (in)

  PIN 1 -- + Antenna
  PIN 2 -- - Antenna

Connecting to an Arduino

Use the J2 pin headers to connect 5 volt and the ground as shown in the picture. Connect the TX (Pin 3) to the Arduino digital pin 2 and RX to digital pin 3 as shown bellow. It is not needed to connect the reset as long as you don't change the default connection speed.


[PROTOCOL-821-880_2_.pdf] describes the protocol used for now we only created a small program to read the RDIF tag number when pressing enter in the Serial monitor of the Arduino IDE

Warning: when writing your sketches use only system, Type-A and Mifare commands. ISO14443-B and ISO15693 are accepted only by RDM880-T-E (not 'A') reader! And as of today (21 may, 2012) remember that this module does not support anticollision for Mifare cards -- sometimes it tells there's more than one card, but there's no way to address the non-default card. It's a firmware issue, confirmed by manufacturer.

#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 3);
char txrxbuffer[255];

char get_readID[] = { 0xAA , 0x00, 0x03, 0x25, 0x26, 0x00, 0x00, 0xBB };
void setup()
    Serial.println("Hit Enter to read the RFID number");

void loop() // run over and over

    int counter = 0;
    if (mySerial.available())

    if (Serial.available()){
        for (counter =0 ; counter < 8 ; counter++){


Tech Support

Please do not hesitate to contact techsupport@seeed.cc if you have any technical issue. Or submit the issue into our forum.