Patent · US Expired

Input/output security system for data processing equipment

US4146929A · kind A · utility

5Cited by
8References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 1, 1977
Grant dateMar 27, 1979
Priority date
Expiry dateMar 1, 1997

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M15/04
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Data processing equipment suitable for recording details of manually connected telephone calls has a plurality of operator stations with keyboards and VDU's connected in groups to operator's control units which respond to keyed instructions to obtain data from peripheral units storing such data and for recording on magnetic tape cartridge the details of the calls. Each operator's control unit is connected to eight operator stations but is capable of handling inputs from twelve such stations. In the event of breakdown of an operator's control units the eight stations allocated to it are divided into two groups of four which are transferred to the two control units adjacent to that which has broken down. Among the criteria used to determine whether a control unit has broken down are the filling of buffer stores and the failure to perform a particular operation within a predetermined interval of time following the previous performance of that operation.

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