The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1993
Filed:
May. 07, 1991
Tim Lee, Owen Sound, CA;
Don Becker, Tara, CA;
Cathy Robins, Owen Sound, CA;
Leo Mullins, Owen Sound, CA;
Bill Oliver, Tara, CA;
Mike Slack, Owen Sound, CA;
General Signal Corporation, Stamford, CT (US);
Abstract
A communication system in which a controller is coupled over a communication path with two or more transponders, at least two of which transponders have different addresses, which controller and transponders communicate by periodically transmitting a broadcast message simultaneously to all transponders, transmitting an acknowledge message indicative of a new input received by at least one of the transponders, and individually polling all of the transponders using a polling technique which incorporates time periods to allow communication between the controller and a selected transponder, wherein the polling is only activated subsequent to the transmission of the acknowledge message. Periodic polls of all transponders in sequence provide supervision of the integrity of the system.