7 facilitate the development: the link layer is fully integrated in the module, very easy to develop. Automatic retransmission function, automatic detection and retransmission of lost packets, the retransmission time and the number of retransmission can be software-controlled automatic storage is not received the packet of the response signal auto-answer, after the receipt of a valid data, the module automatically sends the reply fixed frequency detection signals without any additional programming Carrier Detect – built-in hardware CRC error detection and point-to-multipoint communication address control packet transmission error counter and carrier detection can be used for frequency hopping set can also set up six to receive the channel address, can have a choice of open receive channel standard the pin Dip2.54MM spacing interfaces for embedded applications.