Introduction
This guide explains the RFID/NFC module features and functions. T
Important:
All documents and any examples they contain are provided as-is and are subject to change without notice. Except to the extent prohibited by law, Libelium makes no express or implied representation or warranty of any kind with regard to the documents, and specifically disclaims the implied warranties and conditions of merchantability and fitness for a particular purpose.
The information on Libelium´s websites has been included in good faith for general informational purposes only. It should not be relied upon for any specific purpose and no representation or warranty is given as to its accuracy or completeness.
The standard
RFID (Radio Frequency Identification) is a technology that uses electromagnetic fields to identify objects in a contactless way; it is also called proximity identification. There are 2 elements in RFID communications: the RFID module (or reader/writer device) and an RFID card (or tag). The RFID module acts as the master and the card acts as the slave; this means the module queries the card and sends instructions to it. In a normal RFID communication, the RFID module is fixed and the user takes his card near it when he needs to start the interaction.
An RFID card can be understood as a remote storage unit where we can read and write information without contact. Most of the RFID tags are passive, which implies that the RFID module must create an electromagnetic field in order to power the tag. The RFID card's antenna (in fact it is an inductive coupler) gets the power from this field. Also, an RFID card has a very basic micro-controller which manages the communications and memory access.
Many RFID standards have been released by the industry. Most of them have as operating frequency 13.56 MHz or 125 kHz. In the present document we will be explaining the RFID/NFC module, which works at 13.56 MHz.
In particular, Libelium has created an ISO/IEC 14443-A and NFC compliant module for Waspmote. The ISO/IEC 14443-A protocol is widely accepted as the de facto RFID at 13.56 MHz standard. Billions of ISO/IEC14443-A cards have been sold over the world. NFC (Near Field Communication) is an extension of RFID which focuses on communications between smartphones and other advanced devices. NFC is a set of standards based on previous RFID protocols like ISO/IEC 14443-A.
There are basically 3 ways to interact with an RFID card; Libelium's RFID/NFC module allows the developer to implement the 3 of them:
the RFID/NFC module reads the RFID card's unique identification (UID)
the RFID/NFC module reads the RFID card's internal memory (16 bytes each time)
the RFID/NFC module writes in the RFID card's internal memory (16 bytes each time)
Among the RFID/NFC applications, the most common are:
access control/security
events ticketing
public transport
equipment and personnel tracking
logistics
real-time inventories
marketing information (kiosks)
Last updated
