How does it work?
NFC Tag Click is based on the M24SR64-Y, a dynamic NFC/RFID tag IC with 64Kbit of EEPROM from STMicroelectronics. The M24SR64-Y can write and read in built-in EEPROM up to 246 bytes in separated single commands and can achieve up to 106Kbps of data rate. The EEPROM has a data retention of up to 200 years, and it supports NDEF data structure, 7 bytes unique identifier, and 128 bits password protection. Knowing that the RF interface and I2C can both read or write to the same memory is why only one host can communicate simultaneously with the M24SR64-Y, where the M24SR64-Y controls the management of the interface selection. The NFC (near field communications) is a radio standard for small data volumes and over limited ranges (with the particular PCB antenna on NFC Tag Click, you’ll have a range of about 3cm).
The NFC Tag Click uses an I2C communication interface to communicate with the host MCU over the mikroBUS™ socket. This M24SR64-Y also features the general purpose output pin (GPO). The GPO is enabled when an RF or an I2C session is open. When neither session is available, the GPO is in a high impedance state. The user can select one of these configurations: session open, MIP, WIP, INT, I2C ready response, state mode, or RF busy. There are also three functional modes such as I2C Mode, Tag Mode, and Dual Interface Mode. Besides all mikroBUS™ pins, another additional, such as the DIS pin, can disable RF communication.
This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.
Specifications
Type
RFID/NFC
Applications
Can be used for developing mobile payment systems (for example charging fare in public transport), or for any other short-range wireless data exchange
On-board modules
M24SR64-Y – dynamic NFC/RFID tag IC from STMicroelectronics
Key Features
Compatible with ISO/IEC 14443 type A and NFC Forum type 4 tag, supports NFC data exchange format (NDEF), range of 3 cm, high reliability built-in EEPROM, user-configurable GP signal, RF disable feature, I2C interface, and more
Interface
I2C
Feature
No ClickID
Compatibility
mikroBUS™
Click board size
M (42.9 x 25.4 mm)
Input Voltage
3.3V
Pinout diagram
This table shows how the pinout on NFC Tag Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).
Onboard settings and indicators
Label | Name | Default | Description |
---|---|---|---|
LD1 | PWR | – | Power LED Indicator |
NFC Tag Click electrical specifications
Description | Min | Typ | Max | Unit |
---|---|---|---|---|
Supply Voltage | – | 3.3 | – | V |
Operating Frequency | – | 13.56 | – | MHz |
NFC Range | – | 3 | – | cm |
EEPROM Memory Size | – | – | 64 | Kbit |