ELECTRONIC BORROW CARDS AND PROCEDURES FOR THE PUBLICATION OF AN ELECTRONIC BORROW CARD

摘要

An electronic debit card and a method for recharging the debit card include an integrated semiconductor circuit device having at least one address and control logic circuit and a non-volatile memory. At least one part of the nonvolatile memory is erasable, and memory locations of the region, provided for storing respective value units of the debit card, of the non-volatile memory each being divided up into subregions of different significance. Erasure of the memory locations is possible simultaneously only for all of the memory locations of a subregion of specific significance. Each subregion is capable of erasure only after a carry value has been written into a previously empty memory location of the subregion of the next highest significance. The value units of at least the memory locations of the most significant subregion in a release register of the debit card are assigned release values to be stored, which represent either a release state or a blocking state for the respectively assigned value state of the memory locations of the at least most significant subregion, and raising the card value of the debit card is possible only by changing a release value assigned to the value state of a memory location, from the blocking state into a release state.