RFID Card with UID Rewritable

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  • UID unlock
    • I have been unsuccessful in writing the UID on this card as advertised, using the nfc-mfsetuid program from libnfc. (this program uses a special "unlock" command, the first step of which is transceiving 7-bits of value 0x40; the card does respond to this, but then does nothing else).

I did not receive any documentation with the card, so I am not sure if a different procedure is needed, or if the card is defective. Please advise.

    • Thank you very much for the quick reply! I am embarrassed to tell you that my problem was due to an error on my part calculating a CRC.

I was able to get the reset commands contained in the libnfc source code to work (7-bit 0x40, followed by 8-bit 0x43 for unlock), but I only know these commands from looking at the source code for that project; if there is any documentation for the card, I would very much appreciate it.