Digital key telephone system
US5136585A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1989 |
| Grant date | Aug 4, 1992 |
| Priority date | — |
| Expiry date | Mar 1, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/008
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A key telephone system includes a plurality of ports linked by port associated bidirectional communication channels which are synchronously switched by transferring bit states between ones of the channels to provide communication paths between the ports as directed by a central processor. The ports are also linkable to and via the central processor by port associated message channels. An interface circuit is responsive to the central processor and message channel signals for regulating flow of messages received by the central processor and for effecting single and plural channel distribution of messages from the central processor. The message channels permit telephony operating features and functions to be provided either within the central processor or by appropriate apparatus means being connected at any of the ports. In such a telephone system at least one of said apparatus comprises a telephone station apparatus and another of said apparatus comprises a feature host apparatus. The telephone station apparatus has a plurality of functions stored therein and said feature host apparatus has a plurality of feature modules stored therein. Each such feature module comprises instructio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.