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:
May. 11, 1993
Filed:
Jan. 04, 1991
Gerald A Kammerer, Wrentham, MA (US);
Paul M Piekarski, Cranston, RI (US);
Robert W Coia, North Attleboro, MA (US);
Codex Corporation, Mansfield, MA (US);
Abstract
Apparatus for interfacing a network manager to a network of communication devices over a single communications channel of a plurality of signals is disclosed. Each communication device of the network is uniquely assigned a poll address for communication selection by the network manager which is operative to establish communication with a communication device of the network by transmitting the poll address thereof over the single communication channel. The network of communication devices are coupleable together in a daisy chain through input and output port circuits thereof to form the single communications channel. The input port circuit of each communications device receives and transmits signals from and to the single communications channel upstream of its position in the daisy chain and the output port circuit of each receives and transmits signals from and to the single communications channel downstream of its position in the daisy chain. In addition, the input port circuit of the communication device in the first position of the daisy chain is coupleable to the network manager for receiving signals, including the poll address, therefrom and for transmitting signals thereto. Each communication device further includes a control circuit which is coupleable to both the input and output port circuits thereof for governing the receiving and transmitting operations of each based on the poll address transmitted over the single communications channel by the network manager.