Patent · US Expired

Method and apparatus for communication for a data-storing token

US4928000A · kind A · utility

29Cited by
9References
11Claims
0Family size

Inventors

Key dates

Filing dateAug 19, 1988
Grant dateMay 22, 1990
Priority date
Expiry dateAug 19, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07C9/28
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data-storing token includes a microprocessor which responds to a signal generated by a token interrogator for altering its clock frequency so as to achieve synchronization between the token and interrogator operations. Additional synchronization is achieved by adjusting the length of delay loops in routines used for communication between the token and the interrogator.

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