Verification system, for example for passing through a toll point

Claim 1

A portable object for use with an automatic verification system, comprising: a casing; an electronic circuit in said casing having at least one shift register memory for storing data including an indication of a number of units of value and quality data; an emitter-receiver device in said casing capable of non-contacting coupling to a terminal of the verification system for emitting signals of bits in series corresponding to a read of the data in said shift register, and for receiving signals of bits in series to write data in said shift register; means in said casing for storing check data received from said terminal through said emitter-receiver device; a device for verifying the concordance between a portion of the received check data and first validity data stored in said object to deliver a read authorization; means responsive to a read authorization for delivering the data stored in said shift register memory to said emitter-receiver device, for transmission to said terminal, while recirculating the same data through said shift register memory; a device for verifying the concordance between said check data and second validity data stored in said object and comprising a portion of the data in said shift register memory, to deliver a write authorization, and means responsive to such write authorization for filling said shift register memory with new data received from said terminal, whereby said terminal can change the second validity data upon each rewriting of new data in the portable object, and together with said units of value.