ST25R3911 - ST25DV FTM Problem

[HPARK.1]

Hi.

This is my system.

STM32F103 - ST25DV <-> ST25R3911 <-> STM32F091 <-> CAN <-> PC

In my system, st25r3911 and st25dv communicate through FTM function. ​And the system communicates with a period of 100 msec.

Generally, communication is good, but data is intermittently broken.

I Implemented it based on RFAL. Even if the return rfalST25xVPollerFastReadMessage is ERR_NONE, the data is broken.

So, when the data corruption occurs, I read the FTM of tag using S25R3911 EV board and I check ​the data that is not corruption.

So I always add the CRC code in my message.

Is this normal case?

[Ulysses HERNIOSUS · Accepted solution]

Hi,

from reader perspective I'd say it is not normal. If you want to further investigate if there is a problem in the RFAL I would need at least an SPI trace (best to use a logic analyzer of SPI + IRQ pin).

And best to also re-enable the #if0 code block close to the comment "/* Remove CRC */" inside RFAL. Maybe even move it up.

Alternatively you can also inspect the payload at this place to see if the contained CRC is correct or for some reason the CRC is not checked or not propagated.

Regards, Ulysses

[Ronald B.]

Hello HPARK.1,

I don't see any reason why the data read from the ST25DV-I2C mailbox would be corrupted during the NFC communication.

Each NFC single frame comes with a CRC which is checked by the reader, so any data corruption would be spotted and a CRC error would be returned by the RFAL.

While transferring several frames, a transmission could be missed for instance if the dynamic tag is removed from the reader, but again, a timeout error would be triggered by the RFAL.

As Ulysses said, a SPI trace would help.

And may I ask what board and software are you using for the ST25DV-I2C ?

Regards,

Ronald

[HPARK.1]

I use the ST25DV discovery kit(included Red pcb antenna).

Softwarwe is X-CUBE-NFC5 / v2.0.10 .