ST25 NFC/RFID tags and readers

Hi, I have a question regarding antenna design for my project, creating an NFC reader. I am a beginner (student) when it comes to development. Why is the antenna connected to GND? Does it have to be this way, and is there a detailed explanation somewhere about why it is connected this way?On the ST25R3916-DISCO, it is also laid out but not connected (no solder bridge).  

Hi, is it possible to use the ST25R3916B with an resisitve divider (instead of the capacitive divider) at the RF Inputs to limit the input voltage to a safe value.In case this is possible, is an additional DC-Block needed?I am driving a purely resistive load with the RF Outputs. Thank you very much. Moritz

Hi,I am designing an NFC transmitter that uses ST25R3916B-AQWT. ​The coil will be connected to the RFO1/2 pins. In order to design the coil properly, I will need to know the driver's impedance spec for the various d_res<3:0> multiplier values (Table 78 of the ST25R3916B Datasheet).I was able to find the resistance values and also measure them using a resistor as the load to calculate the driver output impedance (sum of both RFO1/2). It approximately correlated to Table 126 and Table 78. Results and calculation used attached below. I used an oscilloscope to measure the load voltage.  What I am unable to measure with this method, and need to know, is the imaginary part of these measurements. In other words, what the capacitive and inductive loads are as well for at least the RFO1 and RFO2 drive output value (i.e. Table 126). Please let me know if you have these specs or an idea of how to measure. Thanks so much for your help. -Sam

Hi,I've purchased the ST25R3911B-DISCO and it's working fine with ST25PC-NFC.exe.I would like to communicate via uart with ST25R3911B-DISCO in order to implement the tag reading in Labview. There is any document that explain how to create packets to communicate via uart? Or there is any mode of using ST25PC-NFC.exe without GUI and implement the communication via command window? Thank for the support

Hi,I have a new PCB design using the ST25R95 chip.The application : Communicate with a moving tag with a reader (ST25R95). The distance is fixed (5mm) and the tags move under the reader. The problem : there is a dead spot at that distance when the tag is exactly in the center of the reader (at 5mm). I can read the tag coming from left to right, but there is no communication when the tag and the reader are aligned.Is there some parameters I can change like this similar post ? It's not the same chip and this problem occurs with NFC tags on cardboard (no metal bags) https://community.st.com/t5/st25-nfc-rfid-tags-and-readers/nfc-reading-distance-has-a-dead-spot/m-p/675706#M10795Thanks!

Hello, I am trying to use STM32g071rb to control ST25DV16 chip. I found out that we can use middleware X-CUBE-NFC4 to code on stm32cubeIDE better. Question 1 is that when l tried to use I2C1 to connect with ST25DV16, l found out that I2C1 will no longer be automatically initialized in the code, and l wondered why. The second question is that after l configured X-CUBE-NFC4, why won't it initialize in the code as well and l can't initialize it myself because when it tries to do ST25DV_ReadReg() in ST25DV_Init(), the debugger will jump to HardFault_Handler(). The pictures below are my configurations. Thanks.      

Hi,I am implementing the st25r3916 firmware to be used in my reader. I have taken the code of "X-NUCLEO NFC06A1".To make the authentication, I am able to send the command 0x60 + block number; I receive the answer and I send the next message with the key and I receive an answer from the card with length 4 bytes, but I have the status of the reader  "RFAL_ERR_PAR". But when I check the received 4 bytes, they are the right ones. I am using the flags:RFAL_TXRX_FLAGS_CRC_TX_MANUAL|RFAL_TXRX_FLAGS_CRC_RX_KEEP|RFAL_TXRX_FLAGS_NFCIP1_OFF |RFAL_TXRX_FLAGS_AGC_ON|RFAL_TXRX_FLAGS_PAR_RX_REMV|RFAL_TXRX_FLAGS_PAR_TX_NONE|RFAL_TXRX_FLAGS_CRC_RX_MANUALIn order to continue with the reading, I was ommiting this error, and I am sending the command 0x30 to read, with the encryption (I know this part is well done due I have it already running in the st25r3911), in this case I am using next flags:RFAL_TXRX_FLAGS_CRC_TX_MANUAL | RFAL_TXRX_FLAGS_CRC_RX_KEEP | RFAL_TXRX_FLAGS_NFCIP1_OFF | RFAL_TXRX_FLAGS

Does anyone have, or know where I could find, a Radio Test / Radiated Emissions report for the ST25?  It appears to have the appropriate approvals so the report should be available somewhere, but I just can't find it. 

Hi,I need to prepare three modes for the certification testing.1) Always transmit modulated2) Always transmit unmodulated3) Always in receive mode.For no 1, I think I can just set the protocol as an example ISO14443 / ISO15693 then read tag, right?But I have no idea for no 2 and 3. Please help if ST25R95 is able to do it.If there is example code will be much appreciated.Thanks & Best Regards,Rezan  

Hi,I am trying to compile the IOS NFC tap source code and I am getting open ssl & J2Objc hearder not found errors.We are trying to read and write with the ST25DV series of tags.Details Xcode Version :   15.3 min dev            :   15.0Downloaded source code version : 7.4.0Does the Source code support the latest versions of IOS?Any extra steps needed for proper compilation?Error:Compilation error Thanks,Suresh  

 I'm working on writing drivers to use an ST25R3916B to interface with a non-ST host chip as an NFCIP-1 passive communication initiator. I've made progress on the communication to establish an active connection to a tag, but one part I'm stuck on is the response from the SEL_REQ CL1 command message. I'm expecting a 1-byte SAK, but instead I get a 3-byte response: 0x04 0xDA 0x17. When I ignore this response and move to the next stage of anticollision, I do then receive the next 4 bytes of the UID as expected.What do the bytes 0x04 0xDA 0x17 mean in this case? Is it some information about the ST25R3916B's communications or the tag's contents? I looked through the RFAL for reference but could not find any information about the CL1 response, only the command. Any clarification would be appreciated.

Hello everyone,I'm working on a STM32U585 application which works on STOP3 mode and on a customized electric circuit. One of the wake up sources is the ST25's GPO which should generate a pulse when a message is sent via FTM when mailbox is enabled. In fact, GPO is configured to generate a pulse on GPO/RF_PUT_MSG event (mailbox is enabled on DYN Reg).When the microcontroller enters in STOP3 mode, I hold ST25's VCC high so that the tag is not powered (the global current absorption is around 12 microampere). The St25 is powered only when a RF source comes near at it (smartphone, ST25 discovery kit such as ST253911B-DISCO...) and using FTM writes something on mailbox, thus generating a pulse on the GPO and finally waking up the microcontroller. Unfortunately, that is not working. I made sure the coupling between RF source and tag was fine, but no pulse is seen on GPO.If ST25's VCC is held low, the global current absorption goes around 150 microampere and the pulse is generated on

I am attempting to connect to one of ST's CR95HF NFC chips, but I can't get it to respond correctly to the echo command.1) Reset CR95HF by toggling the IRQ line2) Set chip select line low3) Send two bytes : 0x00 0x55 = Command Echo4) Set chip select line high5) Set chip select line low6) Send one byte : 0x03 to request response, waiting for bit 3 to be high7) Set chip select line high8) When bit 3 is high, set chip select line low and send one byte : 0x02 = Read data9) Instead of the expected 0x55, I Receive 0x0EI have checked all the timing diagrams, all timings appear to be ok.I have checked the signals on a scope and digital analyser, all are ok.Any suggestions ?

Hi everyone,Me again :)I'm working on an access control system project and would appreciate some assistance or advice. My goal is to use NFC cards (ISO 14443A) and smartphones (in card emulation mode) as access keys. Specifically, I want to ensure the security of the system beyond just reading the UUID of the card. I aim to read encrypted data from the card instead.I should mention that I'm quite new to NFC technology and don't have extensive knowledge of NFC standards, NDEF messages, and related concepts. My main questions:How can I enhance the security of my NFC access control system?I want to read encrypted data from the NFC cards rather than just the UUID. What are the best practices for encrypting and securely storing data on NFC cards?How can I record an encrypted message on an NFC card?Are there any specific methods or tools that I should use to write encrypted data to the card? How can I ensure that this data can be read securely by the system?How can I achieve this using the R

Hi,I am reading mifare desfire tag which is iso14443-4 compliant using cr95hf.Most of the time, communication is completed successfully but sometime, i am getting 0x90 result code when using SendRecv command.0x90 EUnintByte Residual bits in last byte. Useful for ACK/NAK reception of ISO/IEC 14443 Type A.I do not know how to handle this error and i could not find any information in the iso14443a specifications.Could help me to find resources for this topic?Is it recoverable error or should i stop the communication after getting this error?Regards.

Hello,I am working with an NFC reader with an ST25R3911B chip. The problem I am experiencing is the output power. The power emitted by the antenna is too high; therefore, my task is to reduce the transmitted power.To do this I have relied on reading your application notes. From this extensive reading I realized that there are many possible solutions to reduce the output power, including:- reducing the supply voltage of the chip;- using a single-ended antenna instead of differential antenna configuration;- designing an antenna with higher impedance;- change the antenna driver output resistance;- change the chip internal regulated voltage.Unfortunately, I am working with an already defined differential architecture that excludes the first three options (because would be optimal to not change the current HW structure of the PCB). This allows me to hope for only the last two.First of all I am assuming that these last two options do not require a change in the PCB hardware, if this is true

As written in the title, the ST25PC-NFC software does not detect the STEVAL-25R3916BA reader, despite being in the list of compatible readers. What can I do?Thank you

Hello,I added the RFAL software library to my existing wireless charger project.When I set totalDuration to 50U, there are cases where it cannot detect the card. I get better results when I set totalDuration to 25U. Will it cause problems if I reduce the value of the totalDuration parameter in the library for NFC/RFID card detection? What is range for totalDuration parameter? How should I adjust it?

Hi,I have a X-NUCLEO-NFC08A1 and trying to use ST25R3916B RFAL library with nRF5340 from nordic semiconductor. SPI communication and initialization are working. I am running  demoCycle() function from demo_polling.c. However, in the logs, I receive always null as ID or Block Data.  D: Toggling Wake Up mode OFF D: ISO14443A/NFC-A card found. UID: (null) D: Read Block: OK Data: (null) D: Toggling Wake Up mode ON When I put my phone close to reader I receive following:  D: NFCA Passive ISO-DEP device found. UID: (null) D: Select NDEF Application: OK Data: (null) D: Select CC: OK Data: (null) D: Read CC: OK Data: (null) D: Toggling Wake Up mode OFF Why is it not reading any data? How can I run the demo?

Hey All, I'm looking to bootstrap a custom NFC antenna and was wondering if anyone could point me in the right direction for how to attach a ST NFC chip to a silver nanoparticle printed antenna using a laser jet (with this ink).  Someone suggested using conductive epoxy (like this), but I wanted to post here to see what folks thought. Thanks in advance for any responses!

Hi ST Micro Team. We are planning to start a pilot project on the use of RFID in our office, We want to to place the tags on the laptops so that whenever an engineer with laptop  exits a room the reader should detect. Could you please suggest a possible RFID  evaluation board /reader with possible tags that can be used. Regards,Karthik 

hello,  I'm working on ST25DV64KC, especially on FTM mailbox function and EH power supply. Current situation is I need to test maxium frequency avaliable for supplied by EH(STM32L476VGT6 with ST25DV64KC) while communicating through mailbox(FTM). The plan is to modificate FTM part(of DISCOVERY firmware), and remove all related part of LCD/Touch screen source code, let a data transfer triggered by SW1 button and also compatibility the protocal  used on Andriod app.  However, I found it difficult to use the firmware on FTM because of lack of documentation of the part of source code, as it highly abstracted. So i wonder if there is other way（like some other example project/code provided) or a detailed docmutation i can refer to? thx  analysis only on code is suffering :(  

Hello,I'm trying to use the ST25 java SDK. The software_guide pdf document says I need to load in my IDE the natives libraries the SDK will need. It says I will find them in t \readers\st\resources, but in this folders there is only windows/x86 for the DLLs, and no windows/x64 as is mentionned in the document. And I can't use the 32bits version in my 64bits JVM. Am I missing something, or did the x64 folder was forgotten in the release ?Extract from the pdf guide :the readers/st/resources/windows folder from the sdk :

Is it possible to adjust the slew rate of the RFO1/RFO2 outputs of the ST25R3916B?

Hello all,I would like to download the STSW-ST25R015 software from this page :https://www.st.com/en/embedded-software/stsw-st25r-lib.html#get-softwareUnfortunately it does not work.I am asked to log in when I click on "get latest". But I am already logged in. A download is therefore impossible.Can anyone help? Thanks in advance !regardsThomas