Iso14L4 command group

This command group implements the low-level ISO 14443-4 commands according to the ISO 14443-4 standard. While the ISO 14443-3 Type A and Type B standards define request and selection mechanisms for PICCs, the ISO 14443-4 standard defines a protocol capable of transferring so-called application layer data units (APDUs) with previously selected labels.

Please refer to the ISO 14443-3 (Type A) command group documentation or to the ISO 14443-3 (Type B) command group documentation for more information on how to put ISO 14443-3 (Type A) or ISO 14443-3 (Type B) PICCs into the active state.

APDUs can be transmitted and received to/from a PICC using the Iso14L4.ExchangeAPDU command, provided the PICC is in active state. Before calling the Iso14L4.ExchangeAPDU command, the target PICC has to be selected using the Iso14L4.SetupAPDU command. The Iso14L4.SetupAPDU command furthermore enables to change the communication parameters of the reader to match the capabilities of the target PICC. These communication parameters apply to all following calls of the Iso14L4.ExchangeAPDU and Iso14L4.Deselect commands, until the Iso14L4.SetupAPDU command is called with different parameters. The Iso14L4.Deselect command is used to switch a PICC to halt state after exchange with this PICC has been completed.