This command returns the serial number (UID) of the currently selected card. If VHL.Select hasn't been executed successfully before, the reader will return VHL.ErrCardNotSelected. If the last selected card is no longer available in the antenna field, or a read/write operation failed previous to this command, the returned serial number is undefined.

Don't make security-critical decisions by only examining the card's serial number.


Parameters (request frame)


Returned values (response frame)

Name Type/Size Description
Snr Raw data (until end of frame) Serial number (UID) of the card. The length of this field depends on the selected card type.