| 摘要 |
A money-dispensing system is operative to dispense money in response to a bank customer's embossed credit card and keyed-entry of his personal-identification number, only if this number accords with the customer's account number read from an accounting record impressed from the card. The account number is translated by an encyphering unit into a significantly different number in which each digit is dependent upon the value of more than one of the account-number digits, before the comparison with the keyed-in number. The translation involves filling a shift register with binary-encodings dependent on the account-number digits and the results of repeated execution of an operation in which there is programmed assembly and additive combination of pairs of numbers from different stages of the shift register and feed back into the register of a number dependent on the result of the additive combination. The process of assembly and additive combination of numbers from different stages of the shift register, together with feedback to produce derived-number shifting of the register, is continued after the register has been filled with the account-number derived data, so as to generate the digits of the translated number successively and supply these for comparison in turn with the corresponding digits of the keyed-in number.
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