Change AFI in RFID with NFC

Question

I can't find information about if it's possible change AFI number in RFID chip with NFC. I'm sure it's possible read AFI number with NFC. AFI number has some special block on RFID chip thats reason why I'm not sure if it's possible change it. Thank you

Answer 1

For a ISO 15693 tag you can use the NfcV command transceive(byte[] data) to send a "write AFI" command to the tag, followed by a "Lock AFI" command to lock the AFI value.

Write AFI has the command code 0x27. Lock AFI has the command code 0x28.

This should work as long as the RFID chip supports AFI (AFI is optional) and the AFI of that tag has not been programmed beforehand.

You can find more details about AFI in the ISO 15693-3.

See: See Android reference for transceive()

Answer 2

Have you seen this post about the application family identifier : google

In ISO 15693, the AFI describes the type of application targeted by the reader. This identifier is used to extract all transponders in the reader field that meet the required application criteria. After the reader sends out the AFI, only the AFI-compliant transponders of the appropriate family will respond. Programmed by the transponder issuer, the AFI is read-only and its value cannot be modified.

However I see some systems seem to allow you to write the AFI code, and sa well as lock it. I guess it may be up the individual the chip manufacturer. So while its not locked, I guess you could change it. Who makes your the card you are trying to write to?