STMicroelectronics CRX14 RFID Reader, µPSD3234A, µPSD33xx National ID Reader, SRIX4K National ID Card Application Note

AN1949
APPLICATION NOTE
RFID Reader using STMicroelectronics µPSD MCU and
CRX14 Coupler to Implement a China National ID Card Reader
The National ID Reader is a demonstration of a reader to read the information from a National ID card and
to display the information on a PC. The demonstration is a reference design for the China National second
generation ID card reader using a µPSD32xx or µPSD33xx 8051 core for the microcontroller, and the
CRX14 as the contactless coupler. The demonstration communicates with the PC using the USB or
RS232 interface. The demonstration complies fully with the ISO14443 type-B standards.
HARDWARE DESCRIPTION OF THE NATIONAL ID READER
The whole system can be divided into two main parts: one is the main control board; the other is the boosted antenna board. Figure 1. shows the whole system block diagram.
Figure 1. System Block Diagram
Boosted Antenna Board
Main Control Board
Power Module
PC
USB
I2C
CRX14
Antenna
uPSD3234A
RS232
Security Module
(Reserved for expansion)
AI09743
May 2004
1/22
AN1949 - APPLICATION NOTE
TABLE OF CONTENTS
Hardware Description of the National ID Reader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 1. System Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Main Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Boosted Antenna Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 2. Boosted Antenna Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
CRX14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Debugging Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Test the Output of the CRX14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Test the Output of the Class E Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Optimize the Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 3. Testing the Output of Class E Amplifier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 4. Circuit for the Antenna System on the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Check the Filter and Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 5. Checking the Amplifier Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 6. Checking RFIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
The FIRMWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 7. Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 8. Memory Map and Address Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 9. Firmware Flow Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Communication Protocol between PC and µPSD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Table 1. Read processing: Terminal to PC (Read Data Send) Data Frame Format . . . . . . . . . . . 11
Table 2. . . . . . . .Write processing: PC to Terminal to PC (Write Data Send) Data Frame Format11
Table 3. Terminal to PC (Acknowledgement) Data Frame Format . . . . . . . . . . . . . . . . . . . . . . . . 11
National ID Card Demonstration Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Block 7-9 (11 Bytes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Table 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Block 10-13 (16 Bytes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Block 14-23 (40 Bytes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Block 24-43 (80 Bytes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Summary of the CRX14 Control Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Detailed Description of Key Routines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Porting Strategy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Summary of USB HID Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Table 5. List of Header Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Table 6. List of C Source Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Interface Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
APPENDIX A.Schematic Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 10.Main Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
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Figure 11.Boosted Antenna Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
APPENDIX B.PC Software User Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 12.Running setup.exe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 13.Running setup.exe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 14.Running SIDDemo.exe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 15.Selecting the RS232 or USB Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 16.Keil Compiler Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
APPENDIX C.PSDSoft Design Summary File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
REVISION HISTORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 7. Document Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
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Main Control Board
The main control board contains a uPSD3234A Control Unit, a security module and a power module.
■
The uPSD3234A communicates with the PC using a USB/RS232 interface, and controls the cardreader chip’s operation via the I2C bus. If the security module is used, the uPSD3234A is also
responsible for controlling and communicating with the security module.
■
The security module on this demonstration is reserved for future expansion. If the security
authentication mechanism is to be used, users can just simply put their security module into the
reserved space on the board, and program their own firmware. The basic operation to the security
module is fully compatible with ISO7816 (see the ISO7816 standard and the specific security module
datasheet). The clock of the security module can be provided either from the uPSD3234A’s PWM pin,
or directly from an external crystal oscillator. For details, see Figure 10..
■
The power module provides a stable 5V DC voltage supply to the system. The user should provide
the system with a 9 to 12V DC voltage through the power connector. In this demonstration, for
compatiblity with the µPSD33xx family, a 3.3V DC voltage is also provided.
Boosted Antenna Board
The range of the CRX14, to the tags, can be increased if the transmitted power is increased, and the receive signal is amplified. The boosted antenna circuit block diagram is shown in Figure 2..
Figure 2. Boosted Antenna Block Diagram
Filter and
Amplifier
I2C Bus
CRX14
Class E
Power
Amplifier
Tags
Matching
Circuit
AI09744
CRX14
CRX14 is a short range contactless coupler chip, compliant with the ISO14443 type B proximity standard.
It generates a 13.56MHz signal modulated according to ISO14443 type B proximity standard. The CRX14
features the ST anti-collision mechanism, which allows the reader to detect and identify all the tags that
are present in the operating range, and to access them individually. Because the CRX14 implements the
France Telecom-proprietary anti-clone function, the reader can also perform authentication of tags that
are equipped with the France Telecom anti-clone capability.
The CRX14 coupler interfaces between:
■
the memory tags, on one side, through input/output buffers and the ISO14443 type B radio frequency
protocol, and
■
the system master processor, on the other side, through a 400kHz I2C bus.
Operating from a 5V power supply, and delivered in a SO16N package, the CRX14 coupler chip is an excellent solution for building contactless readers, embedded in the final equipment, and offering a good
compromise between operating range and cost.
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Debugging Procedure
Some debugging might be needed, to make the boasted antenna circuit work properly.
Test the Output of the CRX14. The signal on the RFOUT pin should be 10% ASK modulated on a carry
frequency of 13.56MHz.
Test the Output of the Class E Amplifier. The signal after L7 (test point 2, on the schematic diagram)
should be the amplified signal of RFOUT, as shown in Figure 3.. If there is no signal, you should check the
transistor and the passive components around it.
Optimize the Antenna. The Input Impedance of the antenna (Za), and its matching circuit, should match
the output impedance of the Class E amplifier, see Figure 4.. Because of slight differences among PCB
materials, or other problems, the features of the antenna may vary, such as the inductance (La) of the antenna, and the resistance (Rp). It is necessary to make some adjustment of the antenna matching circuit
to achieve high performance.
Figure 3. Testing the Output of Class E Amplifier
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AN1949 - APPLICATION NOTE
Figure 4. Circuit for the Antenna System on the Board
C1
Ra
Rp
Za
C2
La
AI09745
Since the difference will not be large, the adjustment to the antenna matching circuit is fairly simple, using
an oscilloscope. Using two variable capacitors, substitute these for the C26+C27 and the C28+C31. Their
adjustable range shall be around the original value of C26+C27 and C28+C31 (27pF and 125pF). Then
carefully adjust the capacitors. When the voltage on the antenna loops reaches its maximum value, the
correct value for the capacitor has been found.
For more details, see AN1806: Antenna (and Associated Components) Matching-Circuit Calculation for
the CRX14 Coupler.
Check the Filter and Amplifier. The signal after the operational amplifier (point 3, on the schematic diagram) should be about 3.5V (peak-to-peak) as shown in Figure 5.. The signal on the RFIN pin should be
4.6V (peak-to-peak), as shown in Figure 6..
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Figure 5. Checking the Amplifier Output
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Figure 6. Checking RFIN
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THE FIRMWARE
Figure 7. Block Diagram
Main
(main.c)
Contactless Coupler
Chip and Tag
Control Functions
(CRX14_fncs.c,
SR176_fncs.c)
I2C Driver
(upsd_i2c.c)
UART Driver
(serial.c)
USB Driver
(usb_usr.c,
upsd_usb.c,
usb_desc.c)
Other Drivers
(timer.c)
AI09747
For the purposes of this demonstration, only the Secondary Flash memory of the µPSD has been used.
In Application Programming (IAP) is possible if both main and secondary Flash memory of the µPSD are
used.
Figure 8. Memory Map and Address Space
SECONDARY
FLASH
7FFFh
EXT. RAM
1FFFh
INT. RAM
SFR
FFh
32KB
Indirect
Addressing
7Fh
0000h
Flash Memory Space
(Code Space)
Direct
Addressing
8KB
Indirect
or
Direct
Addressing
00h
2000h
Internal RAM Space
(256 Bytes)
External RAM Space
(MOVX)
(Data Space)
AI09746
Firmware running on the µPSD will mainly control the operation of the CRX14, and communicate with the
PC. Firmware will continuously control the CRX14 to send enquiry signals to the proximity field. If there is
a National ID card within the field, the µPSD will command the CRX14 to read the information from the
card, and to send the information back to the PC via the USB or RS232. When receiving a write command
from the PC, the µPSD will command the CRX14 to write the information to the National ID card.
9/22
AN1949 - APPLICATION NOTE
Figure 9. Firmware Flow Chart
Start
Initialize uPSD
Switch Interface
(USB or RS232)
Fail
Close RF
Pass
Fail
Open RF
Pass
Connect
Tag
Fail
Pass
True
Write Tag
Procedure
Get DLE
from PC?
False
Read Tag
Procedure
AI09748
10/22
AN1949 - APPLICATION NOTE
Communication Protocol between PC and µPSD
<Need to add a few sentences to explain about this custom protocol, such as: is it same for RS-232 and
USB? What is data transfer rate?>
Table 1. Read processing: Terminal to PC (Read Data Send) Data Frame Format
Command (20h)
Len (94h)
Data[0] to Data[m]
CRC16
Table 2. Write processing: PC to Terminal to PC (Write Data Send) Data Frame Format
Command (21h)
Len (94h)
Data[0] to Data[m]
CRC16
Table 3. Terminal to PC (Acknowledgement) Data Frame Format
Status (55h or AAh)
Note: 55h indicates that the write was successful; AAh indicates that there was a write error.
NATIONAL ID CARD DEMONSTRATION STRUCTURE
For this demonstration, the National ID card uses SRIX4K tag, from STMicroelectronics. It involves the
storage of 147 bytes in 37 blocks, mapped in the way described next. In fact, the SRIX4K tag provides
121 blocks (484 bytes) to the user.
Block 7-9 (11 Bytes)
–
ID number (BCD code): 9 bytes
–
Gender and Nation: 1 byte
–
–
Gender: 1 indicates male; 0 indicates female.
–
Nation Code: an integer from 0 to 55, standing for 1 of 56 nations.
Effective period (BCD code): 1 byte
Table 4.
Gender
7
Nation Code
6
5
4
3
2
1
0
Block 10-13 (16 Bytes)
–
Name (Unicode): at most 8 bytes (4 characters) (fixed)
–
Birth Date (BCD code): 4 bytes
–
Issue Date (BCD code): 4 bytes
Block 14-23 (40 Bytes)
–
Issue Department (Unicode): at most 40 bytes (fixed)
Block 24-43 (80 Bytes)
–
Address (Unicode): at most 80 bytes (40 characters) (fixed)
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AN1949 - APPLICATION NOTE
SUMMARY OF THE CRX14 CONTROL DRIVER
The CRX14 control driver consists of four files:
■
upsd_i2c.c
■
upsd_i2cc.h
■
CRX14_fncs.c
■
CRX14_fncs.h
The driver controls the CRX14’s behavior via the I2C interface..
Detailed Description of Key Routines
Explained below are the functions below that may be called by the main program.
int RF_ON(unsigned char *TX, unsigned char *RX)
This function turns on the CRX14’s 13.56MHz carrier out.
–
*TX
pointer to the transmission buffer
–
*RX
pointer to the reception buffer
–
Return value:
0 = success; not 0 = failure (to enable carrier out)
int RF_OFF(unsigned char *TX, unsigned char *RX)
This function turns off the CRX14’s 13.56MHz carrier out.
–
*TX
pointer to the transmission buffer
–
*RX
pointer to the reception buffer
–
Return value:
0 = success; not 0 = failure (to disable carrier out)
int Send_Receive_Data(unsigned char *TX, unsigned char *RX)
This function writes control bytes to the CRX14’s Input/Output frame register, and receives the answer
bytes, that are sent by the TypeB tag, from the Input/Output frame register.
–
*TX
pointer to the transmission buffer
–
*RX
pointer to the reception buffer
–
Return value:
0 = success; not 0 = failure (to get data from the CRX14)
unsigned char upsd_i2c_init(unsigned char Slave_Addr, unsigned char* Data_Ptr, unsigned
char N)
This function initializes the I2C line.
–
Slave_Addr:
Slave address of I 2C device
–
Data_Ptr:
address pointer to the transmission buffer
–
N:
length of data buffer to be transmitted
–
Return value:
not applicable
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AN1949 - APPLICATION NOTE
Porting Strategy
1. Include the four files in your application system
2. According to the the CRX14’s I 2C address that you allocate in your hardware system, make the
corresponding changes in CRX14_fncs.h. For example, if CRX14’s I2C address is 0xA2, then change
#define CRX_ADDR 0xA0;
into
#define CRX_ADDR 0xA2;
3. In your application, set up the transmission and reception buffers for the CRX14 control driver. Each
buffer should be at least 32 bytes in size.
4. According to the oscillator frequency of your hardware system, set the Bus_Freq parameter for the
upsd_i2c_init function
5. Call the upsd_i2c_init function first, before you call other functions. Without a proper initialization
process, the CRX14 may not work properly.
SUMMARY OF USB HID DRIVER
■
Complies with the Universal Serial Bus specification Rev. 1.1
■
Low speed (1.5Mbit/s) device capability
■
Human Interface Device (HID) compatible
See AN1886 for details.
Table 5. List of Header Files
Name
Description
APP_INTR.H
Header shared with Windows USB demonstration application, definition of message formats and
USB demonstration command codes.
uPSD_USB.H
Short header with external definitions of uPSD_USB.c file
USB.H
The main header with USB descriptor and packet structures, USB and HID codes
Table 6. List of C Source Files
Name
Description
USB_USER.C
The main routine(s), USB ISR, command execution
uPSD_USB.C
The main USB driver
uPSD_CFG.C
Short USB configuration file, USB prescaler
uPSD_DEC.C
All USB descriptors and strings
Interface Switch
Firmware switches the interface between USB and RS232 automatically. If the demonstration is connected to a PC with a USB cable, the firmware chooses the USB interface, otherwise it chosen the RS232
interface.
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APPENDIX A. SCHEMATIC DIAGRAMS
Figure 10. Main Control Board
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Figure 11. Boosted Antenna Board
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APPENDIX B. PC SOFTWARE USER GUIDE
1. Run setup.exe and follow the instructions in the setup program (Figure 12. and Figure 13.).
Figure 12. Running setup.exe
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Figure 13. Running setup.exe
2. Run SIDDemo.exe (Figure 14.).
Figure 14. Running SIDDemo.exe
3. Select the appropriate connection, by clicking on its connect button (Figure 15.). (If the RS232
interface is selected, chose the correct com port: the one to which the RS232 cable is connected.)
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Figure 15. Selecting the RS232 or USB Connection
Connect to RS232
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Connect to USB
AN1949 - APPLICATION NOTE
Figure 16. Keil Compiler Settings
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APPENDIX C. PSDSOFT DESIGN SUMMARY FILE
<If the D-flip-flops (En_counter0, En_PA, En_PB, and EnDir0) are not used in this design, they should be
removed from the PSDsoft project so that they will not create questions from customers.>
***********************************************************************
PSDsoft Express Version 8.00
Summary of Design Assistant
***********************************************************************
PROJECT
: rfid
DATE : 04/19/2004
DEVICE
: uPSD3234A
TIME : 12:38:27
MCU/DSP
: uPSD32XX
***********************************************************************
Initial setting for Program and Data Space:
===========================================
Main PSD flash memory will reside in this space at power-up:
Data Space Only
Secondary PSD flash memory will reside in this space at power-up: Program Space Only
Pin Definitions:
================
Pin
Name
-----------tdo
tdi
tck
tms
pd1
USBUSB+
_Reset_In
Vref
Xtal1
Xtal2
Signal
Name
------------------------tdo
tdi
tck
tms
pd1
USB_minus
USB_plus
_Reset_In
VREF
Xtal1
Xtal2
User defined nodes:
===================
Node
Name
-----------En_counter0
En_PA
En_PB
En_Dir0
Node
Type
-----------D-type register
D-type register
D-type register
D-type register
Page Register settings:
=======================
pgr0
pgr1
pgr2
pgr3
pgr4
pgr5
pgr6
20/22
is
is
is
is
is
is
is
not
not
not
not
not
not
not
used
used
used
used
used
used
used
Pin
Type
-----------Dedicated JTAG
Dedicated JTAG
Dedicated JTAG
Dedicated JTAG
GP I/O mode
USB- bus
USB+ bus
Reset In
VREF input
Xtal1
Xtal2
-
TDO
TDI
TCK
TMS
AN1949 - APPLICATION NOTE
pgr7 is not used
Equations:
==========
rs0 = ((address >= ^h2000) & (address <= ^h3FFF));
csiop = ((address >= ^h0200) & (address <= ^h02FF));
csboot0 = ((address >= ^h0000) & (address <= ^h1FFF));
csboot1 = ((address >= ^h2000) & (address <= ^h2FFF));
csboot2 = ((address >= ^h3000) & (address <= ^h3FFF));
En_counter0.re = !_reset;
En_counter0.pr = Gnd;
En_PA := Vcc;
En_PA.ck = Vcc;
En_PB := Vcc;
En_PB.ck = Vcc;
En_Dir0.re = !_reset;
En_Dir0.pr = Gnd;
REVISION HISTORY
Table 7. Document Revision History
Date
27-May-2004
Version
1.0
Revision Details
First Issue
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AN1949 - APPLICATION NOTE
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics.
All other names are the property of their respective owners.
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