Patent · US Expired

Method and apparatus for differentiating simultaneous and sequential key strokes

US5424730A · kind A · utility

19Cited by
3References
37Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 4, 1992
Grant dateJun 13, 1995
Priority date
Expiry dateDec 4, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M11/02
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A method differentiates simultaneous and sequential key strokes by detecting simultaneous key strokes if two keys are pushed within a judging time T.sub.L. The method includes the steps of (a) measuring a first time T.sub.1 from a time when a first key is pushed to a time when a second key is pushed, and a second time T.sub.2 from the time when the second key is pushed to a time when one of the first and second keys is released, (b) comparing the first and second times T.sub.1 and T.sub.2 with an arbitrary threshold function T.sub.C which is set within the judging time T.sub.L, and (c) differentiating whether key strokes of the first and second keys are simultaneous or sequential based on a comparison result of the step (b).

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