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Method and apparatus for determining the validity of data in an integrated circuit card

  • US 5,243,175 A
  • Filed: 04/06/1989
  • Issued: 09/07/1993
  • Est. Priority Date: 04/08/1988
  • Status: Expired due to Term
First Claim
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1. An IC card to be connected to a data processing unit, for communicating data with said data processing unit comprising:

  • storing means for storing a plurality of first data to be transferred to said data processing unit and a plurality of second data corresponding to said first data, each of said second data indicating a term of validity of said corresponding first data;

    timer means for generating present time data;

    determining means which compares said present time data with said second data and determines whether said first data is valid or invalid; and

    erasing means for erasing first data determined invalid by said determining means from said storing means and maintaining remaining first data.

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