US 4,065,752 A · Check digit generation and verification apparatus

Abstract

The specification discloses a check digit verification apparatus having the following novel concepts 1. the use of a read-only store (16) to hold tables of remainder values whereby to obviate the need for multiplication computing ability; 2. the use of remainder values appropriate to the respective digits of an identity number to be verified, and summation of those remainder values to provide an overall remainder value for the identity number; 3. the use of a remainder value accumulating store (23) having a number of stages equal to the modulus of the system, so that the contents of the store is an accumulated remainder value, thus obviating the need for a `division` computing ability; and 4. the use of a register (55) for temporarily storing the digits of an identity number which is to be verified, and for retaining a predetermined initial group of digits after all the digits of the identity number have been transferred into the verification means, whereby to reduce the number of digits that have to be keyed-in when the next identity number for verification includes the retained initial group of digits.

Drawings

Drawings are temporarily unavailable. Open the PDF at USPTO

Drawings

Claims16

Dependent claims

A keyboard apparatus for generating check digits for use with sequences of decimal digits, including

a. a plurality of manually-operable keys of which at least ten (referred to hereafter as decimal digit keys) represent the ten respective decimal digits,
b. a plurality of electric switching means associated with the respective decimal digit keys and operative to change from a first to a second switching state on operation of the associated decimal digit key,
c. electric encoding means having input circuit means connected with the respective switching means, and output circuit means at which are delivered electric "digit value" signals representative of the particular electric switching means then in said second switching state,
d. temporary storage means having input circuit means connected with said output circuit means of said encoding means for receiving therefrom said digit value signals, a plurality of separate storage addresses at which successive digit value signals received from the encoding means during the keying-in of a sequence of decimal digits on said decimal digit keys may be stored temporarily until all of the digits of the sequence have been keyed in, output signal control means, a first output circuit means at which in response to the delivery to said control means of a "sequence complete" control signal are delivered the respective digit value signals then stored in the successive storage addresses, in the sequence in which they had previously been stored in those addresses, and a second output circuit means at which an indexing signal is delivered each time a said digit value signal is delivered to said first output circuit means,
e. control signal generating means connected to said output signal control means and operable on completion of the keying-in of a said sequence of decimal digits whereby to supply a said "sequence complete" control signal to said output signal control means,
f. electric indexing means having input circuit means connected with said second output circuit means of said temporary storage means whereby to receive said indexing signals, and electric output circuit means at which are delivered electric "digit position" signals representative of the respective positions, in a sequence of decimal value signals then being delivered at said first output circuit of said temporary storage means, of the successive digit value signals,
g. a "remainder value" signal producing means comprising an electric storage means having separate storage addresses for holding predetermined "remainder value" signals for each of the respective digit values that may appear in each of the respective digit positions in a said sequence, which storage means has first input circuit means connected to receive said digit value signals from said first output circuit means of said temporary storage means, second input circuit means connected to receive said digit position signals from said output circuit means of said indexing means, and output circuit means at which is delivered in response to corresponding digit value and digit position signals delivered to said first and second input circuit means an electric "remainder value" signal obtained from a storage address corresponding to the digit value and digit position of a decimal digit which is represented by said corresponding digit value and digit position signals,
h. an electric "accumulated remainder value" signal storage means having an input circuit means, first and second output circuit means, and a reset circuit means connected to receive `reset` signals from said output circuit means of said indexing means,
i. an electric adding means having a first input circuit means connected to receive signals from said output circuit means of said signal producing means, a second input circuit means connected to receive signals from said first output circuit means of said signal storage means, and an output circuit means connected to deliver "sum" signals to said input circuit means of said signal storage means, which "sum" signals represent the sum of the signals received at said first and second input circuit means, and
j. an output device connected to receive signals from said second output circuit means of said signal storage means, and having output circuit means at which are delivered, after operation of said control signal generating means whereby to provide a "sequence complete" signal, check digit signals representative of the deviation of the signal then stored in said signal storage means from the nearest multiple of a predetermined modulus number,
each said predetermined remainder value being the excess, over the nearest multiple of the modulus number, of the associated decimal digit value when multiplied by a predetermined multiplier dependent on the position in said sequence of the particular decimal digit.

8 more elements

Dependencies are inferred from the claim text.

Description4,847 words

Summary904 words

#This invention relates to a verification apparatus for use, for example, in checking the digit values and digit order in an identity or reference number, such as a customer's account number.

#The need to verify such digit values and digit order arises, for example, when in completing a transaction (for example, in a department store) the cost of an article to be purchased is to be debited to the customer's account at the store. Verification can avoid wrong accounting, and can ensure on the spot, and at the time of recording the transaction, that the correct account number has been given by the customer and has been correctly registered by the sales assistant or clerk in the accounting and/or sales analysis system in respect of the article to be purchased.

#One verification system known as the "check digit verification system" involves the addition of at least one final `check digit` to a selected account number which is to be allotted to the customer, which check digit (or digits) is determined by a pre-determined scheme of manipulation of the digits of the selected account number, such that when the account number accompanied by the check digit (or digits) is subsequently presented by a customer to a machine or person knowing that scheme of manipulation, that machine or person can carry out, on the spot, a similar manipulation to produce a check number for comparison with the check digit (or digits) given at the end of the account number. If equality is obtained, the account number and check digit (or digits) have been properly presented and can be used in accounting an associated transaction. Thus the use of the check digit(s) or number has allowed the account identity number as presented to the verification apparatus to be verified before the associated transaction is entered.

Brief description of the drawings4 figures

#One check digit verification apparatus, and a modified form thereof, according to the present invention will now be described by way of example and with reference to the accompanying drawings in which:

#FIG. 1 shows a schematic block diagram of the electric circuit connections of the apparatus;

#FIG. 2 shows a table of `remainder` values corresponding to various digit values when appearing in various digit positions in an account identity number;

Detailed description3,824 words

#Referring now to the FIG. 1 a sales register (or an accounting machine terminal) in one department of a departmental store includes a keyboard 10 having keys for giving details of transactions to be debited to customers' accounts to a central data processing and accounting system. These keys include one set 11 for keying in the successive decimal digits of a customer's account identity number, the keys being labelled 0 to 9 respectively.

#Associated with the keys 11 is an encoder 12 which provides a binary output signal appropriate to the key depressed, and a digit position index 13 which is indexed each time one of the keys 11 is depressed and which provides a binary output signal indicative of the number of digits that have been keyed in by depression of the keys 11 since the system was reset at the close of recording a previous transaction.

#Thus, the binary output signal of the index 13 represents the position in a customer's account identity number of the digit just keyed in by depression of a key 11, and the binary output signal of the encoder represents the value of that digit.

Check digit generation and verification apparatus

Life of this patent

Check digit generation and verification apparatus

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims16

Description4,847 words

Drawings

Classification5 codes

Life of this patent

Description4,847 words