TRANSMISSION/RECEPTION DEVICE

摘要

Provided is a transmission device which can continue a consistent and secure communication.  The transmission device includes: a transmission frame counter (20) which counts a value monotonously increasing for each packet and holds the value as a frame counter value; a transmission unit which adds the frame counter value to a packet and transmits the packet to a reception device (200); and a transmission frame counter storage circuit (23) for storing the frame counter value.  When the transmission device is reset by battery exchange or power cut off, the frame counter value stored in the transmission frame counter storage circuit added by a frame counter update interval is held as a new frame counter value.