Check digit verification generation apparatus

Claim 2

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 10 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 switching state, d. electric indexing means having input circuit means connected with each of said electric switching means and being responsive to the changing of any one of said switching means to said second switching state, and electric output circuit means at which are delivered electric ''''digit position'''' signals representative of the position in a sequence of decimal digits being keyed in, by sequential operation of the appropriate decimal digit keys, of the decimal digit last keyed in, e. ''''remainder value'''' signal producing means having first input circuit means connected to receive signals from said output circuit means of said encoding means, second input circuit means connected to receive 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 representative of a Predetermined remainder value corresponding to the digit value and digit position of a decimal digit just keyed in by operation of a selected decimal digit key. f. 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, g. 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 h. 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 the sequence of decimal digits has been keyed in, 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 of said predetermined reminder 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.

Claim 3

Keyboard apparatus according to claim 1, wherein said ''''remainder value'''' signal producing means comprises an electric storage means for holding at separate storage addresses predetermined ''''remainder value'''' signals for each of the respective digit values that may appear in the respective digit positions in a said sequence, and wherein said storage addresses deliver to said output circuit means of said signal producing means said ''''remainder value'''' signals when addressed by corresponding ''''digit value'''' and ''''digit postion'''' signals delivered to said first and second input circuit means of said signal producing means.

Claim 4

Keyboard apparatus according to claim 2, wherein said electric storage means comprises a read-only storage means.

Claim 5

Keyboard apparatus according to claim 1, wherein said signal storage means has a signal storage capacity equal to said predetermined modulus number, so that only the excess of a said ''''sum'''' signal over the predetermined modulus number is stored in said signal storage means.

Claim 6

Keyboard apparatus according to claim 4, wherein said signal storage means comprises a ring counter having a number of stages equal to the said predetermined modulus number.

Claim 7

Keyboard apparatus according to claim 1 wherein the digit value of a check digit appearing in a check digit position is the excess over the nearest multiple of the modulus number of the accumulated remainder value of all the other digits in a said sequence, and wherein said remainder value signal produced by said signal producing means in respect of said check digit value is the complement of said excess.

Claim 8

Keyboard apparatus according to claim 6 including a two state changeover means associated with said signal producing means for enabling said signal producing means to produce in relation to a check digit value ''''remainder value'''' signal representative alternatively of said excess of the accumulated remainder value of the other digits in a said sequence, or the complement of said excess the changeover means being adjustable to one operating state or the other so as to enable the keyboard apparatus to handle digit sequences with ''complement'' check digits or ''true'' check digits respectively as desired.

Claim 9

Keyboard apparatus according to claim 1 wherein digit values of check digits appearing in a plurality of cheCk digit positions sum to produce a decimal value equal to the excess over the nearest multiple of the modulus number of the accumulated remainder value of all the other digits in a said sequence, and wherein said remainder value signals produced by said signal producing means in respect of said check digits sum to produce the complement of said excess.

Claim 10

Keyboard apparatus according to claim 1 for verifying decimal digit sequences which include check digits, wherein the output device has alternatively an output circuit means at which are delivered, after the sequence of decimal digits has been keyed in, two-state electric ''verification'' signals of which the respective states are indicative of the correspondence, and lack of correspondence respectively between the signal then stored in said signal storage means and said nearest multiple of the predetermined modulus number, and wherein said signal producing means delivers at its output circuit means in respect of a check decimal digit appearing in a check digit position in each said sequence a ''''remainder value'''' signal representative of a decimal value which will for correct keyin-in of the digit sequence produce a state of correspondence between said then-stored signal and said nearest multiple of the predetermined modulus number.

Claim 11

Keyboard apparatus according to claim 9, wherein said ''''remainder value'''' signal producing means comprises an electric storage means for holding at separate storage addresses predetermined ''''remainder value'''' signals for each of the respective digit values that may appear in the respective digit positions in a said sequence, and wherein said storage addresses deliver to said output circuit means of said signal producing means said ''''remainder value'''' signals when addressed by corresponding ''''digit value'''' and ''''digit position'''' signals delivered to said first and second input circuit means of said signal producing means.

Claim 12

Keyboard apparatus according to claim 10, wherein said electric storage means comprises a read-only storage means.

Claim 13

Keyboard apparatus according to claim 9, including electrically-controlled inhibiting means for inhibiting other actions of the keyboard apparatus which are to be performed subsequently to the correct keying-in of a said sequence of decimal digits on the decimal digit keys, and means for supplying said verification signals to said inhibiting means whereby to inhibit said other actions whenever the state of a verification signal is indicative of said lack of correspondence between said then-stored signal and said nearest multiple of the modulus number.

Claim 14

Keyboard apparatus according to claim 12, wherein said inhibiting means includes warning means for warning an operator of the keyboard apparatus whenever a subsequent action is inhibited due to an incorrect keying-in of a said decimal digit sequence.

Claim 15

Keyboard apparatus according to claim 9, wherein said signal storage means has a signal storage capacity equal to said predetermined modulus number, so that only the excess of a said ''''sum'''' signal over the predetermined modulus number is stored in said signal storage means.

Claim 16

Keyboard apparatus according to claim 14, wherein said signal storage means comprises a ring counter having a number of stages equal to the said predetermined modulus number.

Claim 17

Keyboard apparatus according to claim 9, wherein the digit value of a check digit appearing in a check digit position is the excess over the nearest multiple of the modulus number of the accumulated remainder value of all the other digits in a said sequence, and wherein said remainder value signal produced by said signal producing means in respect of said check digit value is the complement of said excess.

Claim 18

Keyboard apparatus according to claim 16, including a two state changeover means associated with said signal producing means for enabling said signal producing means to produce in relation to a check digit valUe a ''''remainder value'''' signal representative alternatively of the said excess of the accumulated remainder value of the other digits in a said sequence, or the complement of said excess, the changeover means being adjustable to one operating state or the other so as to enable the keyboard apparatus to handle digit sequences with ''complement'' check digits or ''true'' check digits respectively as desired.

Claim 19

Keyboard apparatus according to claim 9, wherein digit values of check digits appearing in a plurality of check digit positions sum to produce a decimal value equal to the excess over the nearest multiple of the modulus number of the accumulated remainder value of all the other digits in a said sequence, and wherein said remainder value signals produced by said signal producing means in respect of said check digits sum to produce the complement of said excess.

Claim 20

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 10 (referred to hereafter as decimal digit keys) represent the 10 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. ''''remainder value'''' signal producing means having 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 representative of a predetermined remainder value 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.

Claim 21

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 10 (referred to hereafter as decimal digit keys) represent the 10 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. ''''remainder value'''' signal producing means having 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 representative of a predetermined remainder value 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.

Claim 22

Keyboard apparatus according to claim 19 for verifying decimal digit sequences which include check digits, wherein the output device has alternatively an output circuit means at which are delivered, after operation of said control signal generating means whereby to provide a ''''sequence complete'''' signal, two-state electric ''verification'' signals of which the respective states are indicative of the correspondence, and lack of correspondence respectively between the signal then stored in said signal storage means and said nearest multiple of the predetermined modulus number, and wherein said remainder value signal producing means delivers at its output circuit means in respect of a check decimal digit appearing in a check digit position in each said sequence a ''''remainder value'''' signal representative of a decimal value which will for correct keying-in of the digit sequence produce a state of correspondence between said then-stored signal and said nearest multiple of the predetermined modulus number.

Claim 23

Keyboard apparatus according to claim 20, wherein said output signal control means of said temporary storage means includes means enabling said temporary storage means to retain, for future use when handling a next sequence of digit value signals, replicas of at least a predetermined initial group of the digit value signals just delivered via said first output circuit means to said remainder value signal producing means.