发明名称 Revalidatable service supplying system
摘要 The system comprises memory cards and card readers. The card memories (MEM) include validation memory points Vj and credit memory points Ci,j. The addresses of the validation points Vj and the addresses of the associated credit point Ci,j are defined by a reference table (TRR) and a permutation table (TP) which make use of a data item (ZF) which is specific to the card.
申请公布号 US4908499(A) 申请公布日期 1990.03.13
申请号 US19870135095 申请日期 1987.12.18
申请人 SCHLUMBERGER INDUSTRIES 发明人 GUION, CHRISTIAN
分类号 G07F7/08;B42D15/10;G06K17/00;G07F7/02;G07F7/12 主分类号 G07F7/08
代理机构 代理人
主权项
地址