dm00134778

AN4593
Application note
CR95HF C++ Library for Linux User
Introduction
This application note explains how to use CR95HF C++ Library for Linux user
(STSW-95HF004). CR95HF library is developed on Linux platform to expose a number of
APIs that can be used by Linux users to communicate with CR95HF RF transceiver board.
This board is delivered with the M24LR-DISCOVERY kit.
The CR95HF RF transceiver board is powered through the USB port and no external power
supply is required. It is made up of a CR95HF contactless transceiver, a 48 x 34 mm 13.56
MHz inductive etched antenna and its associated tuning components. The CR95HF
communicates with the STM32F103CB 32-bit core MCU via the SPI bus.
A dynamic link library (.so) file is available that can be used by Linux host computer to
manage several functions and communicate with the STM32 MCU and the CR95HF IC.
A Linux command line test application is also available to validate and test the functionality
of developed library.
Figure 1. CR95HF RF transceiver board
Table 1. Applicable tools and software
Type
April 2015
Root Part numbers
Evaluation Tools
M24LR-DISCOVERY
Software
STSW-95HF004
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Contents
AN4593
Contents
1
2
Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1
Connecting the board to your computer . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2
Using the Linux Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2.1
Library creation: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2.2
Test application compilation and execution: . . . . . . . . . . . . . . . . . . . . . . 6
Function Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1
Functions to check USB connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1.1
2.2
2.3
CR95HFlib_USBConnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Functions to communicate with the STM32 MCU . . . . . . . . . . . . . . . . . . 10
2.2.1
CR5HFlib_Echo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2.2
CR95HFlib_MCUrev . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2.3
CR95HFlib_getInterfacePinState . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Functions to communicate with the CR95HF IC . . . . . . . . . . . . . . . . . . . 15
2.3.1
CR95HFlib_Idn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.3.2
CR95HFlib_Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.3.3
CR95HFlib_SendReceive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3.4
CR95HFlib_Read_Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.3.5
CR95HFlib_Write_Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.3.6
CR95HFlib_FieldOff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.3.7
CR95HFlib_ResetSPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
2.3.8
CR95HFlib_SendIRQPulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.3.9
CR95HFlib_SendNSSPulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.3.10
CR95HFlib_STCmd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Appendix A Error codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Appendix B TestApp execution screenshot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
3
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Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
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List of tables
List of tables
Table 1.
Table 2.
Table 3.
Applicable tools and software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
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List of figures
AN4593
List of figures
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
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CR95HF RF transceiver board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Connection of board with Linux Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
TestApp USER MENU screen shot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Option “a” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Option “b” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Option “c” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Option “d” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Option “e” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Option “f” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Option “r” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Option “w” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Option “r” TestApp execution after write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Option “g” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Option “h” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Option “i” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Option “j” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Option “k” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Option “l” TestApp execution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
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1
Getting started
Getting started
This application note and the test application have been written in order to help Linux
developers to easily use CR95HF reader. This application note explains all the functions
exposed by the Linux dynamic link library (.so file) and their description. The extension “.so”
in Linux stands for shared object.
1.1
Connecting the board to your computer
The CR95HF RF transceiver board is connected to the Linux host computer through its USB
port.
The developed library for CR95HF uses “libusb” at the lower level to communicate with USB
connected devices on Linux platform.
libusb is a C library that gives applications easy access to USB devices on many different
operating systems. libusb is an open source project (http://www.libusb.org/).
Figure 2 shows the connection of CR9HF RF transceiver demo board with Linux machine is
through the USB. Libusb based Linux library for CR95HF reader is available on host side
that communicate with the CR95HF firmware running on MCU. CR95HF transceiver
available on demo board communicates with NFC tag through RF communication.
Figure 2. Connection of board with Linux Machine
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Getting started
1.2
AN4593
Using the Linux Library
Below steps are required to be followed to create the library and to run the test application
on any Linux machine (here, Ubuntu machine is taken as Linux host machine).
Pre-Requisite:
“build-essential”, “g++” and “libusb” packages are required to be installed on Linux
machine to proceed for library creation.
If not, please follow below steps:
•
For “build-essential” pkg installation, run the command:
apt-get install build-essential
•
For “g++” pkg installation, run the command:
apt-get install g++
•
For “libusb” pkg installation, run the command:
apt-get install libusb-1.0-0-dev
1.2.1
Library creation:
Unzip the package locally on Linux machine and run the below commands from the location
where package is unzipped.
•
Step 1: Compile the source code and generate object files.
g++ -g -c -Wall -Werror -fPIC -I. HIDManager.cpp libcr95hf.cpp
•
Step 2: Create the library (.so) from object files.
g++ -g -shared -o libCR95HF.so libcr95hf.o HIDManager.o
•
Step 3: Export the path of library to System Library Path so that library can be used by
other applications.
export LD_LIBRARY_PATH= < Path of the generated libCR95HF.so
file>:$LD_LIBRARY_PATH
1.2.2
Test application compilation and execution:
In the package there is a file named TestApp.cpp, it is the test application that can be used
to test and validate the developed Linux library.
•
Step 1: Compilation of test application:
g++ -g –L<Path_to_libusb_library> -L<path_to_CR95HF_library>
TestApp.cpp -o TestApp -lCR95HF -lusb-1.0
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Getting started
Example:
g++ -g -L/lib/x86_64-linux-gnu
lCR95HF -lusb-1.0
-L.
-Werror TestApp.cpp -o TestApp
-
Here, path of libusb library is /lib/x86_64-linux-gnu and path of CR95HF library is same from
where the command is executing.
•
Step 2: Execution of test application
./TestApp
Note:
Please note, this application is needed to be run from “root” to make the application able to
open the device for USB communication.
On the execution, this application displays a number of options for the user to select
depending on which action he want to perform. A screen shot of TestApp execution is
available in the Appendix B.
Whenever a new terminal is opened to build/execute the application, it is required to run the
setp3 to include the path of “.so” file in environment variable “LD_LIBRARY_PATH”.
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Function Description
2
AN4593
Function Description
This section explains about the different functions exposed by the library that can be used
by any other application to communicate with CR95HF reader.
List of Library functions are:
1.
CR95HFlib_USBConnect
2.
CR95HFlib_MCUVer
3.
CR95HFDll_Echo
4.
CR95HFlib_Idn
5.
CR95HFlib_Select
6.
CR95HFlib_SendReceive
7.
CR95HFlib_Read_Block
8.
CR95HFlib_Write_Block
9.
CR95HFlib_FieldOff
10. CR95HFlib_ResetSPI
11. CR95HFlib_SendIRQPulse
12. CR95HFlib_getInterfacePinState
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Function Description
2.1
Functions to check USB connection
2.1.1
CR95HFlib_USBConnect
This function detects if the CR95HF board is properly connected with Linux machine and
lower level driver Libusb available on host side is able to properly communicate with the
board.
Declaration:
int CR95HFlib_USBConnect()
Prototype:
int iResult;
iResult=CR95HFlib_USBConnect();
Input parameter:
None
Output parameter:
None
Returned value:
iResult= 0: No Error
1: CR95HF RF transceiver board not
connected
Example:
Test Application code to validate CR95HFlib_USBConnect()
void Device_Connect()
{
char entry3;
int iResult;
iResult=CR95HFlib_USBConnect();
printf("\n Establishing CR95HR Reader connection through USB \n");
printf("\n --> Library function call : CR95HFlibUSB_Connect() \n");
printf("\n <-- Return from Library function : 0X%x \n",iResult);
if (iResult == 0)
printf("\n SUCCESS : Board connected successfully and ready to use
\n");
else
printf("\n ERROR : Connection failed \n");
printf("\n Selected Task is completed, To proceed for another task put
your
choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
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2.2
Functions to communicate with the STM32 MCU
2.2.1
CR5HFlib_Echo
This function sends a USB request to the STM32 MCU that executes an Echo request on
the CR95HF. The STM32 MCU sends back the answer of the CR95HF, if success, or
returns an error code ‘1’ if there is no answer.
Declaration:
int CR95HFlib_Echo (char* strAnswer);
Prototype:
char strAnswer[50]="";
int iresult;
iresult= CR95HFlib_Echo (strAnswer);
Input parameter:
None
Output parameter:
strAnswer: The CR95HF IC answer to the Echo request is
“5500” if there is no error.
Answer example: “5500”
Returned value:
iResult= 0: No Error
5: CR95HF RF transceiver board not connected
Example
Test Application code to validate CR95HFlib_Echo
void Echo ()
{
char strAnswer[50]="";
char entry3;
printf("\n Echo command sent to MCU \n");
int iresult= CR95HFlib_Echo (strAnswer);
printf("\n --> Library function call : CR95HFlib_Echo (strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if(iresult == 0)
printf("\n SUCCESS : Echo command answer = %s \n", strAnswer);
else
printf("\n ERROR : Echo command failed, no answer \n");
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.2.2
Function Description
CR95HFlib_MCUrev
This function sends a USB request to the STM32 MCU on the CR95HF RF transceiver
board that sends back the revision number of its firmware.
Declaration:
Prototype:
int CR95HFlib_MCUVer(char* StringReply);
char strAnswer[50]="";
int iresult;
iresult= CR95HFlib_MCUVer(strAnswer);
Input parameter:
None
Output parameter:
strAnswer: Firmware revision of the STM32 MCU on
CR95HF RF transceiver board.
Answer example: ““0003010300”
Where:
00: Status byte
03: Size of answer (in bytes)
010300: Revision 1.3.0
Returned value:
iResult= 0: No Error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate CR95HFlib_MCUrev
void Get_MCU_rev ()
{
char strAnswer[50]="";
int iresult;
char entry3;
iresult = CR95HFlib_MCUVer(strAnswer);
printf("\n Get MCU Version request is sent \n");
printf("\n --> Library function call : CR95HFlibUSB_MCUVer(strAnswer)
\n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
printf("\n SUCCESS: MCU Version Reply=%s \n", strAnswer);
}
else
{
printf("\n ERROR : Get MCU Version Failed \n");
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}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.2.3
Function Description
CR95HFlib_getInterfacePinState
This function verifies the communication path between the STM32 MCU and the CR95HF
IC (either SPI or UART).
The STM32 MCU checks which communication configuration is selected on the CR95HF
RF transceiver board.
Declaration:
int CR95HFlib_getInterfacePinState(char*);
Prototype:
char strAnswer[50]="";
int iresult;
CR95HFlib_getInterfacePinState(strAnswer);
Input parameter:
None
Output parameter:
strAnswer: strAnswer: Interface Pin state
Answer example: “80010X”
Where:
80: Status byte
01: Size of answer (in bytes)
0X: Communication mode
With X:
0: Communication in UART mode
1: Communication in SPI mode
Returned value:
iResult= 0: No Error
5: CR95HF RF transceiver board not
connected
Example:
Test Application code to validate CR95HFlib_getInterfacePinState
void Get_InterfacePinState ()
{
char strAnswer[50]="";
int iresult;
char entry3;
iresult = CR95HFlib_getInterfacePinState(strAnswer);
printf("\n Request for getInterfacePinState is sent \n");
printf("\n --> Library function call :
CR95HFlib_getInterfacePinState(strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
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printf("\n SUCCESS: getInterfacePinState completed successfully,Answer
received= %s \n", strAnswer);
if(strAnswer[3]=='0')
{
printf("\n
Communication is in UART mode \n");
}
else
{
printf("\n
Communication is in SPI mode \n");
}
}
else
{
printf("\n ERROR : getInterfacePinState failed, No answer
received\n");
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
2.3
Functions to communicate with the CR95HF IC
2.3.1
CR95HFlib_Idn
This function sends a USB request to the STM32 MCU that requests the IDN of the
CR95HF IC. The STM32 MCU sends back the answer of the CR95HF containing the IDN
value (ASCII codes), if success, or returns an error code ‘1’ if there is no answer.
Declaration:
int CR95HFlib_Idn(char*);
Prototype:
int iresult;
char strAnswer[50]="";
iresult= CR95HFDll_Idn (strAnswer);
Input parameter:
None
Output parameter:
strAnswer: IDN of the CR95HF IC (if no error)
Answer example:
“000F4E4643204653324A415354320075D2”
Where:
00: Status byte
0F: Size of answer (in bytes)
4E4643204653324A41535432: ASCII transcription
of the CR95HF IDN
00: protocol status
75D2: CRC value
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate CR95HFlib_Idn
void Idn ()
{
int iresult;
char strAnswer[50]="";
char entry3;
printf("\n IDN command is sent \n");
iresult= CR95HFlib_Idn (strAnswer);
printf("\n --> Library function call : CR95HFlib_Idn (strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
printf("\n SUCCESS : Idn command response = %s \n", strAnswer);
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else
printf("\n ERROR : no Idn returned \n",strAnswer);
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.3.2
Function Description
CR95HFlib_Select
This function sends a USB request to the STM32 MCU that prepares the CR95HF for
communication by executing a Select request containing the selected RF parameters to the
CR95HF IC.
The STM32 MCU sends back the answer of the CR95HF, if success, or returns an error
code ‘1’ if there is no answer. In addition to selecting the correct RF communication
parameters, this function activates the RF field.
Note:
This is necessary at the start of communications if the RF field was previously switched off.
Declaration:
int CR95HFlib_Select(char*, char*);
Prototype:
int iresult;
char strRequest[50]="";
char strAnswer[50]="";
iresult = CR95HFlib_Select(strRequest ,strAnswer);
Input parameter:
strRequest: Selected RF communication protocol and
certain protocol-related parameters. (This configuration is
used for SendReceive requests.)
For ex: strRequest for ISO15693 HighDataRate 10% One
subcarrier is = "010D":
Where:
“01” is the ISO 15693 configuration
“0D” are the parameters
Output parameter:
Answer: The CR95HF RF transceiver sends back an
answer if the CR95HF is configured correctly and the RF
field is on.
Answer example: “0000”
Where:
“00” is the status byte
“00” is the size of the answer
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
2: Empty argument error
3: Command parameter error
Example:
Test Application code to validate CR95HFlib_Select
void Select_ISO15693 ()
{
int iresult;
char strRequest[50]="";
char strAnswer[50]="";
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char entry3;
printf("\n ISO 15693 Protocol selection for future NFC
communication:\n");
strcpy(strRequest,"010D");
iresult = CR95HFlib_Select(strRequest ,strAnswer);
printf("\n --> Library function call : CR95HFlib_Select(strRequest
,strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
printf("\n SUCCESS : ISO15693 protocol selected : Answer Received=%s
\n", strAnswer);
else
printf("\n ERROR : ISO15693 protocol selection failed :No Answer
Received \n", strAnswer);
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.3.3
Function Description
CR95HFlib_SendReceive
This function sends a USB request to the STM32 MCU that executes a SendRecv
command with data to the CR95HF IC. The STM32 MCU sends back the answer of the
CR95HF, if success, or returns an error code ‘1’ if there is no answer.
Note:
The request uses the SendRecv command to send data using previously selected protocol
and to receive the tag response. For more information, refer to the CR95HF transceiver
datasheet.
Declaration:
Prototype:
int CR95HFlib_SendReceive(char*,char*);
int iresult;
char strRequest[50]="";
char strAnswer[50]="";
iresult=CR95HFlib_SendReceive(strRequest,strTagAnswer
);
Input parameter:
strRequest: The RF Request to be sent by the CR95HF IC
to the Tag (with previously selected ISO format).
ISO 15693 Inventory example: “260100”
Where:
“260100” is the ISO 15693 Inventory command.
Output parameter:
strTagAnswer: The Tag answer if the CR95HF has received
an answer from the Tag in the field; otherwise, an error
code.
ISO 15693 Inventory example:
800D00FF6820492F6A5C02E00CD800
Where
“80” is the status byte
“0D” is the length of the entire data field
“00FF6820492F6A5C02E0” is the data received from
the tag
“0CD8” is the original received CRC value
“00” is the protocol error status
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
4: Communication error
Example:
Test Application code to validate library function CR95HFlib_SendReceive
void Send_ISO15693_Inventory ()
{
int iresult;
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Function Description
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char strRequest[50]="";
char strTagAnswer[50]="";
char entry3;
strcpy(strRequest,"260100");
iresult=CR95HFlib_SendReceive(strRequest,strTagAnswer);
printf("\nISO15695 inventory using CR95HF SendReceive command:\n");
printf("\n --> Library function call : CR95HFlib_Select(260100
,strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if ((strTagAnswer[0] == '8') & (strTagAnswer[1] == '0')) //CR95HF Tag
answer OK
{
printf("\n SUCCESS : Tag answer=%s \n",strTagAnswer);
}
else
{
printf("\n ERROR : No tag answer received \n",strTagAnswer);
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.3.4
Function Description
CR95HFlib_Read_Block
This function will read the particular block of Tag memory. This function takes the block no.
as a input parameter and sends back the 4 byte data available at that particular block.
Declaration:
Prototype:
int CR95HFlib_Read_Block(int,unsigned char*);
nt iresult;
int RegAdd;
unsigned char strTagAnswer[50]="";
iresult = CR95HFlib_Read_Block(RegAdd, strTagAnswer);
Input parameter:
RegAdd: Address of register of which data is required
Output parameter:
strTagAnswer: array of unsigned char to contain the 4 bytes
data available at RegAdd
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
4: Communication error
Example:
Test Application code to validate library function CR95HFlib_Read_Block
void Read_Block()
{
char entry3;
unsigned char strTagAnswer[50]="";
int RegAdd=0;
printf("\n This option will read 4 byte data of the block entered by user
\n");
printf("\n");
printf("\n please enter the Block address in hex \n");
printf("\n");
scanf("%x", (int*)&RegAdd);
int r = CR95HFlib_Read_Block(RegAdd, strTagAnswer);
printf("\n --> Library function call : CR95HFlib_Read_Block(RegAdd,
strTagAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",r);
if(r==0)
{
printf("\n SUCCESS : Received Tag answer=%s \n",strTagAnswer);
for(int i=3;i<=6;i++)
{
printf("%x",(int)strTagAnswer[i]);
printf(" ");
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}
}
else
{
printf("\n ERROR : No tag answer received \n",strTagAnswer);
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
This test application asks the user to enter the register address of which data is needed to
be read. After the execution of function it returns the 4 bytes data available at that particular
location separated by space.
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2.3.5
Function Description
CR95HFlib_Write_Block
This function writes the data into particular block of Tag memory. This function takes the
block number and the data needed to be written on memory as the input parameter.
Declaration:
Prototype:
int CR95HFlib_Write_Block(int,unsigned char*,unsigned
char*);
int iresult;
int WriteAdd;
unsigned char strTagAnswer[50]="";
unsigned char strBytestowrite[50]="";
iresult = CR95HFlib_Write_Block(WriteAdd,
strTagAnswer,strBytestowrite);
Input parameter:
WriteAdd: Address at which data is needed to be written
strBytestowrite: array of unsigned char to store the 4 bytes
of data which is required to be written on memory of Tag
Output parameter:
strTagAnswer : The Tag answer if the CR95HF has received
an answer from the Tag in the field; otherwise, an error code
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
4: Communication error
Example:
Test Application code to validate library function CR95HFlib_Write_Block
void Write_Block()
{
char entry3;
unsigned char strBytestowrite[50]="";
unsigned char strTagAnswer[50]="";
int WriteAdd;
printf("\n This option will write 4 bytes of data entered by user into
the selected block\n");
printf("\n");
printf("\n please enter the Block address in hex");
printf("\n");
scanf("%x", (int*)&WriteAdd);
printf("\n enter first byte \n");
scanf("%x",(int*)&strBytestowrite[0]);
printf("\n enter second byte \n");
scanf("%x",(int*)&strBytestowrite[1]);
printf("\n enter third byte \n");
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scanf("%x",(int*)&strBytestowrite[2]);
printf("\n enter fourth byte \n");
scanf("%x",(int*)&strBytestowrite[3]);
printf("\n");
int r = CR95HFlib_Write_Block(WriteAdd, strTagAnswer,strBytestowrite);
printf("\n --> Library function call : CR95HFlib_Write_Block(WriteAdd,
strTagAnswer,strBytestowrite) \n");
printf("\n <-- Return from Library function : 0X%x \n",r);
if(r==0)
{
printf("\n SUCCESS : Data written into the block
successfully\n",strTagAnswer);
}
else
{
printf("\n ERROR : data write on block is failed \n");
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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2.3.6
Function Description
CR95HFlib_FieldOff
This function sends a USB request to the STM32 MCU to switch off the CR95HF RF Field.
The STM32 MCU sends back the answer of the CR95HF, if success, or returns an error
code ‘5’ if there is no answer.
Declaration:
Prototype:
Int CR95HFlib_FieldOff(char*);
int iresult;
char strAnswer[50]="";
iresult= CR95HFlib_FieldOff (strAnswer);
Input parameter:
None
Output parameter:
strAnswer: The CR95HF RF transceiver sends back an
answer and the RF Field is switched off.
Answer example: “0000”
Where:
“00” is the status byte
“00” is the size of the answer
Returned value:
result:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate library function CR95HFlib_FieldOff
void FieldOff ()
{
int iresult;
char strAnswer[50]="";
char entry3;
printf("\n FieldOff command is sent \n");
iresult= CR95HFlib_FieldOff (strAnswer);
printf("\n --> Library function call : CR95HFDll_FieldOff(strAnswer)
\n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
printf("\n SUCCESS : RF Field Off ok = %s \n", strAnswer);
else
printf("\n ERROR : RF Field Off command error \n",strAnswer);
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
2.3.7
AN4593
CR95HFlib_ResetSPI
This function resets the CR95HF IC in case of a problem. This function only resets the
CR95HF IC and not the STM32 MCU.
Declaration:
Prototype:
int CR95HFlib_ResetSPI(char*);
int iresult;
char strAnswer[50]="";
iresult = CR95HFlib_ResetSPI(strAnswer);
Input parameter:
None
Output parameter:
strAnswer: The CR95HF RF transceiver sends back an
answer if the SPI has been correctly reset.
Answer example: “8000”
Where:
“80” is the status byte
“00” is the size of the answer
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate library function CR95HFlib_ResetSPI
void Reset_SPI ()
{
char strAnswer[50]="";
int iresult;
char entry3;
iresult = CR95HFlib_ResetSPI(strAnswer);
printf("\n Reset_SPI request is sent \n");
printf("\n --> Library function call : CR95HFlib_ResetSPI(strAnswer)
\n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
printf("\n SUCCESS: Reset SPI successfully,Answer received= %s \n",
strAnswer);
}
else
{
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Function Description
printf("\n ERROR : Reset SPI failed, No answer received\n");
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
2.3.8
AN4593
CR95HFlib_SendIRQPulse
This function must be used when the CR95HF RF transceiver is configured in SPI mode
(communication between the STM32 MCU and the CR95HF IC). The interrupt pulse is sent
to the CR95HF IRQ pin.
Declaration:
int CR95HFlib_SendIRQPulse(char*);
Prototype:
int iresult;
char strAnswer[50]="";
iresult = CR95HFlib_SendIRQPulse(strAnswer);
Input parameter:
None
Output parameter:
strAnswer: The CR95HF RF transceiver board sends back an
answer if the IRQ
Pulse was correctly sent.
Answer example: “8000”
Where:
“80” is the status byte (see Appendix A for error codes)
“00” is the size of the answer
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate library function CR95HFlib_SendIRQPulse
void Send_IRQPulse ()
{
char strAnswer[50]="";
int iresult;
char entry3;
iresult = CR95HFlib_SendIRQPulse(strAnswer);
printf("\n Send IRQPulse request is sent \n");
printf("\n --> Library function call : CR95HFlib_SendIRQPulse(strAnswer)
\n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
printf("\n SUCCESS: Send IRQPulse completed successfully,Answer
received= %s \n", strAnswer);
}
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Function Description
else
{
printf("\n ERROR : Send IRQPulse failed, No answer received\n");
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
2.3.9
AN4593
CR95HFlib_SendNSSPulse
This function sends an interrupt to wake up the CR95HF IC. It can be used when the
CR95HF Demo board is configured in UART mode. The interrupt pulse is sent to the
CR95HF NSS pin.
Declaration:
Prototype:
int CR95HFlib_SendNSSPulse (char*);
it iresult
char strAnswer[50]="";
iresult = CR95HFlib_ SendNSSPulse (strAnswer);
Input parameter:
None
Output parameter:
strAnswer: The CR95HF RF transceiver board sends back
an answer if NSS
Pulse was correctly sent.
Answer example: “8000”
Where:
“80” is the status byte (see Appendix A for error
codes)
“00” is the size of the answer
Returned value:
result:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate library function CR95HFlib_SendNSSPulse
void Send_NSS_Pulse ()
{
char strAnswer[50]="";
int iresult;
char entry3;
iresult = CR95HFlib_SendNSSPulse(strAnswer);
printf("\n Request for Send NSS_Pulse \n");
printf("\n --> Library function call : CR95HFlib_SendNSSPulse(strAnswer)
\n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
printf("\n SUCCESS: Send NSS pulse successfully,Answer received= %s
\n", strAnswer);
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Function Description
}
else
{
printf("\n ERROR : Send NSS Pulse failed, No answer received\n");
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n");
scanf("%c", &entry3);
}
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Function Description
2.3.10
AN4593
CR95HFlib_STCmd
This function is used to send any request to CR95HF IC. The STM32 MCU receives the
frame contained in the request and send it directly to the CR95HF IC. The STM32 MCU
sends back the answer from CR95HF IC to the PC through USB port. The frame has to be
formatted according to the CR95HF datasheet.
This function can be defined as a “Transparent Mode” command.
The CR95HF formatted frame has to be sent through this CR95HFlib_STCmd function. “01”
is prepend in the frame as the header byte.
Declaration:
Prototype:
int CR95HFlib_STCmd(char*,char*);
it iresult
char strAnswer[50]="";
char strAnswer[50]="";
iresult = CR95HFlib_STCmd(strRequest,strAnswer);
Input parameter:
strRequest : is the frame which will be directly send to
CR95HF IC. This
frame is prepended by an additional byte “01”
Example:
For select protocol ISO 15693, strRequest will be
“010202010D”
Where:
“01” is the transparent command header byte
“0202010D” is the protocol select frame
“02” is Protocol Select Command
“02” is the request length
“010D” are protocol select parameters
Output parameter:
strAnswer: The CR95HF RF transceiver board sends back
an answer
Answer example: “0000”
Where:
“00” is the status byte (see Appendix A for error
codes)
“00” is the size of the answer
Returned value:
iresult:
0: No error
5: CR95HF RF transceiver board not connected
Example:
Test Application code to validate library function CR95HFlib_STCmd(char*,char*)
void STCmd_ISO15693()
{
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Function Description
char strRequest[50]="";
char strAnswer[50]="";
int iresult;
char entry3;
strcpy(strRequest,"010202010D");
iresult = CR95HFlib_STCmd(strRequest,strAnswer);
printf("\n ISO15693 Protocol select using CR95HFlib_STCmd function \n");
printf("\n --> Library function call :
CR95HFlib_STCmd(strRequest,strAnswer) \n");
printf("\n <-- Return from Library function : 0X%x \n",iresult);
if (iresult == 0)
{
printf("\n SUCCESS: ISO15693 protocol is selected through STCmd,
Answer received= %s \n", strAnswer);
}
else
{
printf("\n ERROR : ISO15693 protocol select through STCmd failed,
Answer received= %s \n", strAnswer);
}
printf("\n Selected Task is completed, To proceed for another task put
your choice");
printf("\n"); scanf("%c", &entry3);
}
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Error codes
AN4593
Appendix A
Error codes
Table 2. Error codes
Error code
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Description
0000
Answer OK
8000
Answer OK
8200
Invalid command length
8300
Invalid protocol
8600
Communication error
8700
Frame wait time out OR no tag
8800
Invalid Start Of Frame
8900
Receive buffer overflow (too many bytes received)
8A00
Framing error (start bit = 0, stop bit = 1)
8B00
EGT time out (for ISOIEC 14443-B)
8C00
Invalid length. Used in Felica, when field length < 3
8D00
CRC error (Used in Felica protocol)
8E00
Reception lost without EOF received
8F00
No field
FD00
Time out - no answer from Tag detected by the CR95HF IC
FE00
Unknown error
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TestApp execution screenshot
Appendix B
TestApp execution screenshot
Below is the screen shot of TestApp execution to explain how application executes, what are
different options available and how the output will appear on the screen for user.
Figure 3. TestApp USER MENU screen shot
Figure 4. Option “a” TestApp execution
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Figure 5. Option “b” TestApp execution
Figure 6. Option “c” TestApp execution
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TestApp execution screenshot
Figure 7. Option “d” TestApp execution
Figure 8. Option “e” TestApp execution
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Figure 9. Option “f” TestApp execution
Figure 10. Option “r” TestApp execution
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TestApp execution screenshot
Figure 11. Option “w” TestApp execution
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Figure 12. Option “r” TestApp execution after write
Figure 13. Option “g” TestApp execution
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TestApp execution screenshot
Figure 14. Option “h” TestApp execution
Figure 15. Option “i” TestApp execution
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Figure 16. Option “j” TestApp execution
Figure 17. Option “k” TestApp execution
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TestApp execution screenshot
Figure 18. Option “l” TestApp execution
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Revision history
3
AN4593
Revision history
Table 3. Document revision history
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Date
Revision
14-Apr-2015
1
Changes
Initial release.
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IMPORTANT NOTICE – PLEASE READ CAREFULLY
STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, enhancements, modifications, and
improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on
ST products before placing orders. ST products are sold pursuant to ST’s terms and conditions of sale in place at the time of order
acknowledgement.
Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or
the design of Purchasers’ products.
No license, express or implied, to any intellectual property right is granted by ST herein.
Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product.
ST and the ST logo are trademarks of ST. All other product or service names are the property of their respective owners.
Information in this document supersedes and replaces information previously supplied in any prior versions of this document.
© 2015 STMicroelectronics – All rights reserved
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