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AS3900

Data Sheet - Detail ed Description

8.6 Pairing

8.6.1 Procedure

Pairing is a procedure where the Clients send their device IDs to the Master. The pairing procedure need to be started by the MCU. Common

data-rate, frequency deviation and communication mode must be configured in the MAIN Register of all devices which have to be paired. After

successful pairing, the device identification number is stored to the first free ID-table position at the Master and the pairing bit at the Client needs

to be set.

The Pairing procedure is usually done permanently and initialized by the Master. The AS3900 is also able to provide the Pairing initialized by the

Client and can also be just temporarily. The following table gives an overview about the provided Pairing features of the AS3900:

3

If the wakeup receiver of the client detects a wakeup Signal (OOK

pattern) the wakeup detection stays active as long as the OOK

pattern is received. The wakeup detection mode is left after the OOK

pattern goes low or the wakeup activity lasts for more than 3 wake

activity was terminated due to the reason that the wakeup signal is

side has to calculate a random delay (less than 1sec).

4

When the wakeup call is finished the Master switches

automatically the FSK receiver on for 1sec (the 1sec could be

transmit randomly their first data. (if any of the Clients were

already connected before, the timer based communication is

suspended)

5

6

The received packets from different Clients contain a

Preamble, the ID, Timing information (Cycle time and random

pointer), data length, and data and CRC information. The

exchange of the actual time code is terminated by an

automatic acknowledgement (ACK).

Table 23. Pairing Procedure

Pairing Procedures

Description

Client initiates permanent Pairing

Master is set to receive mode and listens during periodic time windows for a Wakeup Call from

the Client. The Clients sends the Wakeup Call in order to wakeup the Master and transmits the

first data packet. The Master wakes up and receive the first data packet that ID is checked. If

the ID is not already in the ID-Table of the Master and the CRC is correct, the new ID will be

inserted. After a handshake with the Client (acknowledgement), both nodes pass into Standby

Mode again.

Table 22. Wakeup Procedure Initialized by the Master

Step

Master

Client