AN2399 datasheet(9/22 Pages) STMICROELECTRONICS

9 / 22 page

AN2399

Overview of RFID reader using STR710

9/22

Overview of RFID reader using STR710

The RFID reader is developed using the STR710 ARM7TDMI powered microcontroller and

the CRX14 low cost contactless coupler chip. Communication between the microcontroller

and the coupler is achieved by an I2C bus.

The RFID library has been developed to support SR176 tag.

As depicted in picture below, the RFID library has been developed on a 4-layer structure.

Using the application layer, the tag may be used as an EEPROM with read/write operation. It

is not necessary to know how STR710 communicates with the CRX14 coupler chip and how

CRX14 communicates with SR176 tag.

Figure 1.

Architecture details

7.1

CRX14 demonstration kit

A demonstration kit has been created to interface CRX14 with the STR710 microcontroller

via I2C. Further details can be found in the application note AN1806. The demonstration kit

schematic and layout are shown below.

Application layer: applications dedicated

functions

RF Commands layer: Initiate(), Select(),

Completion(), GetUID(), Read_Block(), Write_Block()

Transceiver Commands layer: CRX14 registers

management

I2C Bus layer: I2C protocol to interface CRX14

RFID reader/writer

SR176 Commands

CRX14 Commands

I2C Commands

STR710

CRX14

Tag

I2C

RF - ASK Mod

RF-BPSK mod

Firmware specifications

RFID firmware for STR710 supports SR176 tag

Firmware is developed on a 4 layer structure:

AN2399 Datasheet(PDF) 9 Page - STMicroelectronics