Patent · US Expired

Method and apparatus for discrimination between different kinds of data transmission

US4850008A · kind A · utility

35Cited by
17References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 29, 1988
Grant dateJul 18, 1989
Priority date
Expiry dateFeb 29, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S379/902
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A data communication station comprises a first and second data terminals operating under first and second transmission standards, and a selective switching means to connect those terminals to a single communication line; the first data terminal is usually a teleprinter or other character-by-character terminal capable of operating under applicable standards such as those for Economy Telex or for DDD (Direct Distance Dialing) ASCII transmissions, whereas the second data terminal may be a facsimile machine or other graphics terminal operating under the CCITT T-series standards. In one embodiment the switching means is a free-standing control unit that may be connected to virtually any conventional data terminals; in another version the switching means is incorporated in an input/output board in one data terminal and utilizes a part of the logic of that data terminal. The switching means normally maintains the two data terminals connected to the communication line with each in its on-hook condition; in response to the ring signal of an incoming call, both data terminals initially go off-hook. The switching means then disconnects one terminal (usually the facsimile terminal) from the li…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.