04435706 is referenced by 25 patents and cites 6 patents.

A plurality of remote stations are sequentially addressed by a master controller to ascertain the status of associated sensing devices. The addresses are each comprised of a sequence of sinusoidal waveforms which are counted by the remote stations and compared with a preselected station number. Each addressed station responds by driving a communication line to a low voltage level for a time interval determined by the status of its associated sensing device.

Title
Switch network
Application Number
6/317474
Publication Number
4435706
Application Date
November 2, 1981
Publication Date
March 6, 1984
Inventor
John E Callan
Milwaukee
WI, US
Agent
Barry E Sammons
Assignee
Allen Bradley Company
WI, US
IPC
H04Q 9/00
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