ST25R3911 Reading T2T cards fails

[LYU4662]

hello,

  Currently I use nfc5 demo to read T2T card, but the read often fails,The code is as follows.When NFC-A is detected, the type is 0, and the card is considered to be T2T

static void demoT2t(void)

{

  ReturnCode err;

  uint16_t rcvLen;

  uint8_t blockNum = 0;

  uint8_t rxBuf[16];

  err = rfalT2TPollerRead(0, rxBuf, sizeof(rxBuf), &rcvLen);

  printf("err %d\r\n", err);

  platformLog(" Read Block %d: %s %s\r\n", 0, (err != ERR_NONE) ? "FAIL" : "OK Data:", (err != ERR_NONE) ? "" : hex2Str(rxBuf, rcvLen));

}

These cards are detected in the code as T2T type, and there is no encryption, and I can see from the app read that the keys are all 0xFF，I wonder what went wrong, thanks

[Brian TIDAL]

Hi,

such tags are not true T2T tags as a proprietary three pass authentication is required before memory operation. See https://community.st.com/t5/st25-nfc-rfid-tags-and-readers/nfc0541-read-mifare-classic-1k/td-p/255197 for similar question. I would suggest to use true T2T tags such ST25TN rather that tags with proprietary authentication and ciphering which are broken since several years.

Rgds

BT