st25r3916 FCC Modulation wave output

[JSH2]

Hello

We are preparing the following modes for the authentication test.

1) Unmodulated signal continuous output (typo corrected!)

2) Modulated signal continuous output

3) Adjust each signal output dB

1 and 3 have been resolved, and we are having difficulty outputting 2 modulation signals.

So far, RFAL functions cannot output modulated signals continuously, and the driver code for ST25R3916 must be configured, but it has not been successful yet. (1, 3 are implemented as RFAL functions)
The way I want to use it is "Start function call -> modulated signal continuous output" and "Stop function call -> output end".
 
What I've tried now is that I've been working with rfalNfcWorker() 

For "RFAL_NFC_STATE_POLL_TECHHDETECT", we fixed "gNfcDev.state" to "RFAL_NFC_STATE_LISTEN_TECHHDETECT" instead of "RFAL_NFC_STATE_STATE_DISCOVERY". Is this the right way?

[Brian TIDAL · Accepted solution]

Hi,

do you mean 1/ continuous unmodulated field and 2/ continuous modulated field?

For similar questions, see:

Solved: How do i get into testmode with continuous unmodul... - STMicroelectronics Community

Solved: ST25R95 Certification testing - STMicroelectronics Community

Rgds

BT

[JSH2]

Dear Brian,

Thank you for your response.

After reviewing the materials via the link, my understanding is that to continuously output a modulated signal:

1. Set the protocol (e.g., ISO14443 / ISO15693) and read a tag.

2. Select the reader protocol and use the SendRecv command.

I’m using the NFC library and RFAL (app_x-cube-nfcx.c / demo_polling.c / RFAL code), but I’m not sure how to implement the above approach within this stack.

Do you have any additional references or example code you could share?

Thank you again for your kind support.

Best regards,

[Brian TIDAL]

Hi,

The following API functions can be used:

• rfalSetMode(): Use this function to set the mode/protocol (for example, RFAL_MODE_POLL_NFCA) and the bit rate.
• rfalTransceiveBlockingTxRx() or rfalStartTransceive()/rfalGetTransceiveStatus(): Use these functions to send and receive data.

Note: The statement "continuously output a modulated signal" is more or less irrelevant for an NFC reader device due to the half-duplex nature of the protocol.

Rgds

BT

[JSH2]

HI!

While I understand this is not meaningful given the protocol’s half-duplex nature, continuous transmission of a modulated signal is required to meet the certification requirements.

Continuous modulation (OOK/AM depth measurement, etc.) is required, but RFAL is meaningless, right? Then, I think it should be processed in Stream/Transparent mode (direct control of register) of ST25R3916.

Thank for Your Help! 

If I have any questions again, I'll ask you a question.

[Brian TIDAL]

Hi,

If you transmit a "long enough" frame using the RFAL, it should be seen as "continuous transmission of a modulated signal" and it should be ok for the FCC testing.

My comment was more a general comment related to the FCC testing in case of half duplex system. 

Rgds

BT