Digital key system architecture
CA 1333418 C · Owner: Mitel Corporation · Inventors: Mitchell, William Creighton; Coomber, Mark Robert; Hatherill, Richard Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A digital communication system comprised of a universal backplane bus and a plurality of interface circuits connected to remote peripherals for effecting bidirectional communication of information signals between the remote peripherals via the bus, as well as the exchange of message signals between local control circuitry resident on individual ones of the interface circuits. Each interface circuit is further comprised of a digital time and space switch for transmitting the information signals in PCM format between the remote peripherals and the universal bus, under control of the control circuitry resident on respective ones of the interface circuits. An HDLC controller is provided on each …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted December 6, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 6, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.