Patent · US Expired

CRT key station which is responsive to centralized control

US4041469A · kind A · utility

6Cited by
7References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 13, 1974
Grant dateAug 9, 1977
Priority date
Expiry dateDec 13, 1994

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G5/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Hardware duplication at each of a plurality of CRT key stations is minimized and centralized control is maintained by performing many traditional CRT key station operations under software control by a central processing unit. Simplified CRT key stations include circuitry providing automatic key stroke repeat for continuously actuated keys only after receipt of a repeat enable signal from the central processing unit for each separate repeat and a tone generator responsive to commands from the central processing unit. The tone generator includes a key click circuit to audibly indicate each completion of key activation. CRT key station circuitry inserts a configuration code with each key stroke data word which indicates one of a plurality of available key switch arrangements for the CRT key station. The configuration code permits a single key station hardware design to be included in a data entry system with different keyboard configurations such as typewriter, calculator, keypunch or even foreign language to be selected without need for a conversion system at each CRT key station to convert key stroke information to a common code. Instead, a central processing unit may utilize the co…

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