pyscan can not read the nfc tag



  • Hi,

    I uesd the code of pyscan library, and ran the code named nfc.py. When the nfc tag touched the nfc antenna, I counld only got an incomplete (4 byte) uid, which actually has 7 byte uid. Onther data in fan sectors, ,such as URL, written in the nfc tag can not be read. The function of nfc.mf630_MF_auth reading sector data never successed. I am not sure the reason for it. The type of nfc tag is ISO 14443-3A, NXPMIFARE Ultralight C.

    Can anyone give me suggestions? Thank you.

    Mia CHEN



  • @mia1913 don’t know the details of the interface / library, but at a low level, 7 and 10-byte UUIDs are actually transmitted in several round trips.

    For a 7-byte UUID, only 3 bytes of the UUID are returned, and the other byte is a special value which means “there’s more”. You then do another request which returns the remaining 4 bytes.

    No idea how this is/should be handled on the Pyscan, though.


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