House coding of alarm devices with RF functionality

Abstract

Devices such as fire alarm devices form a system in an efficient manner with less user time required and no need for a network control device or a pre-assigned house code. A device receives a message called a house coding message (HCM) from other devices in range. Each HCM has a signature representing a house code table (HCT) in each other device. Each receiving device reads (102) a serial number (SN) in the message. The device checks (104) if this SN already exists in its house code table (HCT).If not, it (105) adds the SN and its Repeat Level value to the HCT. There is (110) an iteration for each SN in the HCM until the HCM has been fully processed.The device calculates a new signature for its HCT. Importantly, if (112) this signature value is the same as that for all of the SNs in the received HCM then house coding is complete. If not (114), the device generates and sends (116) a fresh HCM, and this is received by all of the other devices within RF range. There are multiple cycles until all of the signature values in the HCM which are generated are the same.

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