I have a question about NFC implementation using ST25R3911B.

[HJUNG.1]

1    Question

-. Please give me a solution for Phenomenon 1 or 2.

2    Phenomenon 1

-. ISO 18092 (NFCIP-1) Active P2P mode 106 kbps

-. Transmit and receive work but have a low success rate.

3    Phenomenon 2

-. ISO 18092 (NFCIP-1) Active P2P mode 212 kbps

-. Receive success rate is high, but no transmission.

Thank you for your help.

Please check the attached document.

1. NFC_Questions_200408.xlsx
2. NFC_Questions_200408.docx

[Brian TIDAL]

Hi,

it seems that you have your own ST25R3911B driver for this application. ST does provide an NFC communication stack and driver for ST25R3911B (C source code that can be ported to many MCU, see X-CUBE-NFC5 source package). This package supports AP2P communication and the default demo provides an example of AP2P communication. I believe that using this source package would reduce your effort to have NFC AP2P communication.

Rgds

BT

[Ulysses HERNIOSUS · Accepted solution]

Hi,

I see one major issue in your code for 212/424: You need to configure the modulation depth by either manually adapting register 26h to some good value for AM, e.g. 0xb9 or to set the desired modulation depth accordingly in 24h and issue Adjust Modulation Depth command.

Missed bits in 106 kbps could be caused by too late enabling the receiver. I am not sure how you actually enable the receiver or when the Squelch is taking place. If you want to continue this route then I advise to investigate using a logic analyzer together with observation mode 4.

In general I advice to base your work on RFAL which also implements workarounds for known issues. E.g. the Analog Preset commands puts some filter/receiver settings to values which are not ideal for 212/424. In the following thread you will find advice to achieve AP2P communication between two 3911B using the RFAL:

https://community.st.com/s/question/0D50X00009q4jyzSAA/connect-two-xnucleonfc05a1-with-peer-to-peer-p2p-connection

Regards, Ulysses