5.2 Passive Communication

The TRF7970A ISO Control register (0x01) sets the modulation of the transceiver RF field when it is in initiator mode and the bit rate at which to load modulate the initiator's field when it is in target mode. Unlike active communication, the target load modulates the initiator RF field instead of modulating its own field. Furthermore, the anticollision procedure is different for passive communication and active communication.