Circuit for interfacing a processor to a line circuit

US4495614A · kind A · utility

Assignee

• International Telephone and Telegraph Corporation · US

Inventors

• Enn Aro · Raleigh, US
• Leonard Edward Bogan, Jr. · Columbus, US
• Richard A. Hamersley · Columbus, US
• Paul H. Knapke · Columbus, US
• Robert L. Miller · South Bend, US

Key dates

• Filing date: Apr 22, 1982
• Grant date: Jan 22, 1985
• Expiry date: Apr 22, 2002

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04Q11/0407
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A line switch for a digital telephone switching system utilizes distributed processing. The line switch comprises one or more switch modules. Each switch module is coupled to a central office switching system via one or more PCM lines which utilize common channel signaling. Each switch module comprises groups of line circuits, each line circuit being coupled to a subscriber line. Three separate distributed processor functions are provided in each line switch module. A first processor is utilized to communicate with the central office switching system and to coordinate the operations within the line switch module. A second processor is provided to control clock generation and rate conversion circuits. Each group of line circuits includes a third processor to control the operations of the line circuits and to gather information from the line circuit. A busing arrangement is provided within the line switch such that both control information and PCM voice data are routed throughout the line switch. A standardized interface circuit is provided which interfaces each line circuit to the third processor and also to the busing arrangement.