How to read the system file of an NFC TAG?

[mwhitecliff]

I have a STM32U5 with an ST25R3911B and an ST25TV02KC NFC TAG using RFAL.

I would like to format an empty NFC TAG to store an NDEF text message. My setup works perfectly if I initially write an NDEF text record with my smartphone. But if I write to an empty NFC out of the shelf, the NfcType5_NDEFDetection() function reports the NDEF_ERROR_NOT_FORMATED error. Sure I can write the CC-File, but how do I know the size of the memory? Well yes, I know the size of the memory for this TAG (datasheet) but I would like to make it dynamically to support other TAGs too.

So my intention was, to read the RFAL_NFCV_SYSINFO_REQ_ALL where I can get the MEM_SIZE_INFO of the TAG. But this does not work. I use the rfalNfcvPollerGetSystemInformation() function for this which reports a timeout.

On my Smartphone, I have the ST25 Application and I can read the system file with the memory size of the TAG.

How can I read this with my ST25R3911B? Or is there even an easier way to format the TAG? The only thing missing from the CC-File is the memory size...

Regards

Marc

[Brian TIDAL · Accepted solution]

Hi,

I would recommand to use the NDEF middleware from the latest delivery of the ST25R embedded library. This includes a ndefT5TPollerTagFormat API.

rfalNfcvPollerGetSystemInformation should work to retrieve the mem size (if you have a timeout, then probably one of the parameters is incorrect).

Rgds

BT

[mwhitecliff]

Hi Brian

Thank you for the hint. I will have a look at the new library. I used an older one.