What is the low level command to create multiple ndef files in a st25ta 2k tag

[ARey.1]

Hello,

I'm searching the low level command to create multiples ndef files in a st25ta 2k tag.

I know that there is a field in the system file that specifies the number of ndef files, but it is read only, so it isn't possible to specify the number of ndef files with an update binary command.

I know it is possible to create multiple ndef files because on the software st25pc-nfc, there is a field where we can specify the number of ndef files we want, but it is high level and i don't know how it works.

It is not possible either to update the CC to add the TLV of a new ndef file because it is read only too.

I've searched on the tag datasheet, there is a topic, the 7.8 called : create and update an ndef file, but it doesn't explain at all how to create an ndef file.

Best regards.

[NFC/RFID Customer support]

Hello,

the length of the CC file only depends on NDEF file number :

• 1 NDEF file : CC File length = 15 bytes (0x000F)
• 2 NDEF files : CC file length = 23 bytes (0x0017)
• ...
• 8 NDEF files : CC file length = 71 bytes (0x0047)

CC File Length = 7 bytes + NDEF file number * 8

To anticipate the length of the CC file before reading it, just read the 2 first bytes of the CC file that is the CC file length, then read the global CC file data with the CC file length value.

Best regards,

NFC Customer support.