Checkout system

A merchandise checkout system is disclosed including a credit card reader operated by the customer to obtain credit information used in totalizing the merchandise transaction. A data terminal is utilized by the checkout operator to total the amount of the purchased items. Simultaneously with the operation of the data terminal, the customer operates the credit card reader to read a credit card inserted into the card reader by the customer and on which is magnetically encoded the amount of money, i.e. balance of account, available for use by the customer. If the amount available is greater than the total amount of the purchased items, the total amount is subtracted from the available amount with the result displayed and printed on the receipt and journal records of the data terminal as the amount paid. If the available amount is less than the total amount of the purchased items, the amount available is subtracted from such total of purchased items and the difference displayed as the amount due which is to be paid by the customer to complete the transaction.

BACKGROUND OF THE INVENTION 
The present invention relates to a merchandise checkout system in which an 
electronic cash register or terminal device is used in conjunction with a 
credit card reader to increase the speed of the checkout operation. The 
use of credit cards, either in the form of small plastic cards, plates or 
the like has become so widespread in merchandise transactions that the 
checking of credit authorization through use of the credit card is a 
standard part of today's merchandising checkout operation. Most prior art 
credit card systems store credit information at a central data station. In 
response to the submission of an account number from a remote credit 
reader, the system provides information relating to the account. For 
instance, the system may indicate that the credit card has been stolen, 
has expired, whether the account has been overdrawn or may indicate the 
dollar amount of available credit. One system magnetically imprints a 
dollar amount on the credit card that may be spent during a predetermined 
length of time. After a sales transaction is completed, the system 
subtracts the amount of the transaction from the available balance and 
rewrites the new balance on the card. Other systems will simply store the 
new balance at the central station. Common to all of these prior checkout 
systems which include a terminal device and a credit card reader is the 
requirement for the operator to operate the credit card reader after 
totalling the merchandise to check if the customer is authorized to use 
the credit card in paying for the merchandise purchased. This requires the 
customer to give the credit card to the operator with the operator then 
inserting the card in the card reader orientated in a predetermined 
position to provide a valid read operation. Such requirement measurably 
increases the time of the checkout operation in addition to complicating 
the checkout routine of the operator, the latter tending to increase 
operator errors during the checking of the merchandise at peak hours. 
Prior art arrangements have also been directed to systems for identifying 
the owner of the card or to provide a visible indication that the credit 
card is valid and may be used in paying for the merchandise purchased. In 
all cases, the operator is again required to perform the card reading 
operation. It is therefore a primary object of this invention to provide a 
merchandise checkout system capable of executing a checkout operation 
which includes a credit authorization procedure in the minimum amount of 
time. It is a further object of this invention to provide a checkout 
system which includes a terminal device and credit card reader, both of 
which are operated simultaneously by the checkout operator and the 
customer respectfully. It is another object of this invention to provide a 
checkout system in which the amount read from the credit card is entered 
into the data terminal and used to prepare the customer's receipt showing 
the amount paid and, in case of a credit balance less than the total of 
the merchandise amount, the money amount due from the customer to complete 
the sales transaction. 
SUMMARY OF THE INVENTION 
In order to carry out these objects, there is provided a checkout system 
which includes a data terminal device, a card reader and a data processing 
unit for controlling the operation of the terminal and the reader to allow 
simultaneous operation of each during the checkout operation. The system 
contemplates the use of an identification card in the form of a credit 
card issued by a bank for each of its customers and on which is encoded an 
identification number and the amount of money available to the customer 
for use in purchasing merchandise items. The data terminal device is 
utilized by the operator to check out the items purchased by the customer. 
The card reader is utilized by the customer to read an identification 
number encoded on the card in checking the identity of the customer, the 
amount of money available for merchandise purchase and other necessary 
data for checking the validity of the card. This data is transmitted 
automatically to the data processing unit. A keyboard on the card reader 
is also utilized by the customer to insert a secret identification number 
which is compared by the data processing unit with the identification 
number read from the card which will match if the customer is the true 
owner of the card. If the card is valid, the amount of money available is 
automatically entered into the data terminal device as the amount against 
which the amount due for the purchased merchandise item is to be applied. 
If the available amount is not equal to the amount due, the data terminal 
device displays the difference between the amount available and the amount 
due which is required to be paid by the customer to complete the 
transaction. A receipt record showing details of the transaction is 
printed and issued to the customer. At the same time the available amount 
status of the credit card is caused to be updated to reflect the present 
sales transaction. The inputting of the data read by the data read by the 
card reader to the data processing unit is controlled by a priority 
interrupt unit which allows for the simultaneous operation of the card 
reader and the terminal device. 
The invention will be better understood from the following detailed 
description of one preferred embodiment thereof with reference to the 
accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to FIG. 2, there is shown a plan view of the checkout system 
in accordance with the invention which includes a plurality of data 
terminal devices 20 which may be of the type shown and described in U.S. 
Pat. No. 3,866,175, issued Feb. 11, 1975 to Lloyd R. Seifert, Jr. and Joel 
H. Hinrichs, Jr., and which is assigned to the assignee of the present 
application. This patent is incorporated herein by reference. The terminal 
device 20 is mounted at the front portion of a checkout counter 22 within 
which is located a credit card reader 24 which is positioned so as to be 
accessible to the customer for operation thereby when he or she is 
standing next to the counter 22. The card reader 24 is connected to the 
data terminal device 20 by means of electrical cable 26 with each of the 
terminal devices 20 being connected to a store controller 28 by means of 
an electrical cable 30. As fully disclosed in the above Seifert et al., 
U.S. Pat. No. 3,866,175, the store controller 28 includes a central 
processing unit for processing the data received from a plurality of I/O 
devices which may include the terminal devices 20 and the credit card 
readers 24 of the present embodiment. The present checkout system will be 
described in connection with the use of an NCR 255 data terminal device 
and an NCR 726 store controller, the structure and function of each being 
fully disclosed in manuals and other texts published by the NCR 
Corporation, of Dayton, Ohio. Included in these publications, which are 
also incorporated herein by reference, are manuals (RM-0272) directed to 
the NCR 255/726 system, (MS-00264) concerning the 255 terminal, and 
(MS-00266) concerning the 726 controller. The card reader 24 may be of the 
type disclosed in the copending application of Diane P. Kerkhoff, Ser. No. 
563,436, filed Mar. 31, 1975 and which was allowed in June 22, 1976, now 
U.S. Pat. No. 3,996,450. This application is assigned to the assignee of 
the present application and is further incorporated herein by reference. 
Data inputted into the controller 28 from the I/O devices is appropriately 
assembled, processed and then outputted to the I/O devices for display, 
printing, etc. In the checkout system of the present embodiment, the 
processed data from the controller 28 will be transmitted to the terminal 
device 20 for printing on both a receipt and a journal record, the 
processed data including data received from the terminal device 20 and the 
credit card reader 24. 
Referring now to FIG. 3, there is shown a functional block diagram of each 
of the devices which are included in the present checkout system. Included 
within the store controller 28 is a communication adapter 32 for 
controlling the transmission of data between an I/O device and the 
controller, -- the I/O device being the data terminal 20 in the present 
application -- a cassette tape recorder 34 for recording and storing data 
of each sales transaction on magnetic tape, an interface unit 36 connected 
to the communication adapter 32 and the recorder 34, a minicomputer 38 and 
a memory unit 40, both connected to the interface unit 36. The 
communication adapter 32 in the controller 28 is connected over the cable 
30 to a communication adapter 42 located in one of the data terminal 
devices 20. As disclosed fully in the Seifert et al., U.S. Pat. No. 
3,866,175, there is one communication adapter 32 in the controller 28 for 
each data terminal device 20. Also included in the data terminal device 20 
is an interface unit 44 connected to the communication adapter 42 over 
line 46, a keyboard 48 for inputting merchandise data to the interface 44 
over line 50, a bar code reader 52 which reads data from coded information 
located on the merchandise item concerning the merchandise item, -- the 
reader 52 inputting the data read into the interface 44 over line 54 --, a 
display device 56 for displaying information processed in the controller 
28 and a printer unit 58 for receiving and printing on the customer's 
receipt and the journal record information concerning the sales 
transaction such as the price of each item sold, the total amount of the 
sales transaction, the amount tendered for payment of the sales 
transaction, the amount due from the customer to complete the sales 
transaction and any other information that is deemed necessary for 
inclusion on the customer's receipt and the journal record. 
Also included in the terminal device 20 is a priority interrupt unit 60 for 
controlling the timing of the processing of the input/output data 
transmitted between the controller 28, the terminal device 20 and the 
credit card reader 24 attached to the terminal device over cable 26 (FIG. 
2). As shown in FIG. 3, the priority interrupt unit 60 receives data over 
line 62 from the communication adapter 42 which in turn receives the data 
from the controller 28. Data is also received by the interrupt unit 60 
from the printer unit 58 and from an interface unit 64 over the cable 26 
located in the credit card reader 24. Data read from a credit card 
inserted into the card reader 24 by the customer will be transmitted to 
the terminal device 20 under the control of the priority interrupt circuit 
unit 60. The interface unit 44 in the data terminal device 20 is also 
connected to the interface unit 64 in the credit card reader 24 over the 
cable 26 for transmitting data between the terminal device 20 and the card 
reader 24. 
Also included in the data terminal device 20 is a microprocessor 66 and an 
associated memory unit 68 for processing data entered into the terminal 
device 20 from the credit card reader 24 in the situation where the 
terminal device 20 operates independently of, i.e. off-line from, the 
controller 28. In the present embodiment, it is assumed that the 
minicomputer 38 in the controller 28 provides the data processing 
functions of the present checkout system with the microprocessor 66 of the 
terminal device 20 controlling the flow of data between the terminal 
device 20 and the card reader 24 in addition to checking the 
identification of the customer as will be described more fully 
hereinafter. In any case, it is obvious that the microprocessor 66 of the 
terminal device 20 can be used to provide all the processing functions of 
the checkout system performed by the minicomputer 38 that will be 
described hereinafter if the checkout operation is limited to a stand 
alone terminal operation. It is also obvious, as disclosed in the Seifert 
et al., U.S. Pat. No. 3,866,175, that the checkout system disclosed herein 
will operate utilizing only the minicomputer 38 for the processing 
operation. 
The credit card reader 24 (FIG. 3) includes, in addition to the interface 
64, a security check keyboard 70 for use in checking the identification of 
the credit card holder, an input display device 72 for displaying 
information concerning the operation of the card reader and the secret 
identification number of the customer, a read/write transport 74 for 
magnetically reading data from the credit card and for writing new data 
onto the card and a printer 76 for printing information from the credit 
card on a record member during the operation of the credit card reader. As 
shown in FIG. 6, the identification or credit card 77 utilized by the 
customer in the present embodiment may include at least one stripe of 
magnetic material 79 located therein. The magnetic stripe may consist of 
one or more tracks of prerecorded information or data which may include 
date of expiration, account number, bank number and a secret 
identification number. The customer is informed of the secret number and 
is told to remember it. As described more fully hereinafter, when the 
customer inserts the credit card into the card reader 24, the assigned 
secret number must be entered into the keyboard 70 of the card reader. If 
a predetermined relationship exists between the secret number read from 
the customer's credit card and the secret number entered by the customer 
and other conditions are met, the display 56 will be operated to display 
the validity of the credit card for use in the sales transaction. 
Referring to FIG. 4, there is shown a functional block diagram of the 
interface unit 64 of the credit card reader 24 together with details of 
the display device 72 and the keyboard 70. Included in the unit 64 is an 
encoder 78 connected over line 80 to the security check keyboard 70 for 
encoding in binary form a secret identification number inserted by the 
customer into the keyboard 70, a control circuit unit 82 for controlling 
the operation of the read/write transport 74 and the printer 76, lamp 
drivers 84 for operating lamps on a character number display device 86 and 
an instruction display device 88, each device being part of the display 72 
(FIG. 3), an interrupt request circuit 90 and an interface unit 92. As 
seen in FIG. 4, the interface unit 92 is interconnected with the encoder 
78, the lamp drivers 84 and the control circuit 82 while the interrupt 
request circuit 90 is connected to the encoder 78 and the control circuit 
82. The functional relationship of each of the elements found in FIG. 4 
will be described more fully hereinafter with respect to the flow diagram 
of FIG. 1. 
Referring now to FIG. 5, there is shown a plan view of the keyboard of the 
credit card reader 24 which includes the security check keyboard 70 and 
the display 72 (FIGS. 3 and 4). Included in the display device 72 is an 
instruction display device 88 (FIGS. 4 and 5) comprising a plurality of 
indicating lamps 94, 96, 98, 100, 102 and 104, together with appropriate 
legends indicated by the numeral 105 for instructing the customer on the 
sequence of operation to be performed on the card reader 24. It can be 
seen from FIG. 5 that lamps 94, 98, 102 and 104 will provide the normal 
operation of the card reader 24 in which the secret identification number 
is introduced into the checkout system by the customer for use in checking 
the validity of the identification or credit card 77 (FIG. 6). Lamps 96 
and 100 indicate a failure of the previous operation and to initiate a new 
card reading operation. Also included in the card reader 24 are a 
plurality of character number display lamps 106, 108, 110 and 112, with 
appropriate numerical indicia 1-4, inclusive, located thereabove (at 114) 
for indicating the number designation of each character in the secret 
identification number as they are inserted into the security check 
keyboard 70 by the customer. The number of lamps can of course be expanded 
to accommodate larger number designations. Below the display 72 on the 
card reader 24 are a plurality of numerical keys 116 comprising the 
security check keyboard 70 for use by the customer to manually insert the 
customer's identification number and a reset key 118 for resetting the 
keys 116 if a mistake in entry has been made by the customer. 
Referring now to FIG. 1, there is shown a flow diagram of the operation of 
the checkout system according to the present invention. Upon delivery of 
the purchased merchandise items to the checkout counter 22 (FIG. 2), the 
operator will check out each item by indexing (block 120) the price of the 
item together with a department identification code and any other data 
that may be associated with the item being purchased into the keyboard 48 
(FIG. 3) of the data terminal device 20 in a manner that is well known in 
the art. As fully disclosed in the Seifert et al. U.S. Pat. No. 3,866,175, 
data entered into the keyboard 48 of the terminal device 20 is transmitted 
through the interface 44 (FIG. 3), the communication adapter 42 and over 
cable 30 to the minicomputer 38 in the controller 28 for processing and 
storage. The minicomputer 38 will generate a return message which operates 
the printer 58 in the terminal device 20 to print on the receipt and the 
journal (block 122) the data as entered into the keyboard 48. This 
operation will continue until all the merchandise items being purchased 
are registered through the keyboard 48 and a total operation (block 124) 
of the items being purchased is completed and printed. 
If the customer intends to purchase the merchandise items with the use of a 
credit card 77 (FIG. 6), he or she will insert the credit card (block 126) 
into the credit card reader 24 at the same time the operator is checking 
out through the keyboard 48 the items being purchased. While the credit 
card of the present embodiment is of the type in which the amount 
available for use, i.e. balance of account, is magnetically encoded on the 
card 77 (FIG. 6), it is obvious that other types of credit cards may be 
used where the available amount is stored in the minicomputer portion of 
the controller 28 and outputted to the data terminal device 20 when 
required. The function of the credit card reader 24 is to read the amount 
on the credit card 77 that is available for use by the customer in 
purchasing merchandise items, to write the new balance of the amount 
available after the total of each sales transaction has been subtracted 
from the previous balance or available amount, and to provide data which 
is used in checking the validity of the credit card presented by the 
customer. 
Upon the customer's insertion of the credit card 77 (FIG. 6) within the 
card reader 24, the read/write transport 74 (FIG. 3) will be operated to 
read from the magnetic stripe 79 (FIG. 6) an identification number, the 
available balance, and any other information that may be required (block 
128--FIG. 1). As illustrated in FIG. 4, the data read from the credit card 
by the read-write transport 74 is transmitted through the control circuit 
82 located in the interface unit 64 of the card reader 24 (FIG. 3.). Such 
unit 64, upon receiving this data, will control the interrupt request 
circuit 90 (FIG. 4) causing the priority interrupt unit 60 of the data 
terminal 20 (FIG. 3) to send an interrupt signal through interface 44 to 
the microprocessor 66 and thereby interrupt the operation of the 
microprocessor 66 in the terminal 20 so that it may receive a certain 
portion of the credit card contained data. In the present application, the 
microprocessor 66 will be utilized to check the identification number of 
the customer (as input by customer through keyboard of credit card reader 
and as read by credit card reader from customer inserted credit card) 
although it is obvious that the minicomputer 38 in the store controller 29 
could also be utilized in the same manner if so desired. Thus, the 
microprocessor 66 will receive the identification number portion of the 
credit card 77 data while the remaining data from such card is transmitted 
to the minicomputer 38 in the store controller 28. The minicomputer 38 
upon receiving this remaining data will store the available amount balance 
and utilizes the rest of the data to check the validity of the credit 
card. This may include determining whether the card is stolen, whether the 
account is overdrawn, or other desired determinations indicating card 
misuse. All functional operations of the terminal device 20 and the credit 
card reader 24 are controlled by programs stored in the minicomputer 38. 
As fully disclosed in the previously-cited Seifert et al., U.S. Pat. No. 
3,866,175 and in the Class 255 NCR Manual (MS-00264), the terminal device 
display 56 (FIG. 3) includes a plurality of instructions pertaining to the 
operation of the terminal device 20, which display 56 is similar to the 
instruction display device 88 of the card reader 24. The illumination of 
these instructons in both the display 56 and the display 88 is controlled 
by the minicomputer 38 in a predetermined sequence to provide a 
step-by-step checkout operation. 
At the start of the checkout operation, the lamp 94 (FIG. 5) in the 
instruction display device 88 will be illuminated to instruct the customer 
to insert the credit card within the card reader 124. After the insertion 
of the credit card 77 (FIG. 16) and with the receiving of the data so read 
by the card reader, the minicomputer 38 will cause the lamp 98 to light 
instructing the customer to index the appropriate numerical keys 116 in 
the keyboard 70 (FIG. 5 and block 130 of FIG. 1) to enter his or her 
secret identification number in the manner disclosed in the 
previously-cited co-pending Kerkhoff application, Ser. No. 563,436, now 
U.S. Pat. No. 3,906,450. Indexing of the card reader keys 116 by the 
customer results in each numerical character of the identification number 
being outputted over line 80 to the encoder 78 (FIG. 4) which converts the 
identification character into a 4 bit binary word. This binary word is 
then transmitted through interface 92 and over line 26 through interface 
44 to miroprocessor 66 under the control of the priority interrupt 60 in 
the same manner as the data read by the read/write transport described 
above. 
Upon receiving each numerical character of the secret identification number 
from the credit card reader 24, the microprocessor 66 will operate the 
display 72 of such reader 24 through the lamp drivers 84 (FIG. 4) to 
display the entered numerical character by utilizing lamps 106, 108, 110 
and 112 of the character number display 86 (FIG. 5) and to light lamp 102 
(FIG. 5) in the instruction display device 88 indicating that the 
processing of the data is occurring. If the customer inadvertently 
depresses the wrong keys 116 when entering the identification number, the 
operation can be repeated by depressing the reset 118 (FIG. 5) and 
repeating the keying in operation. The microprocessor 66 compares (block 
132--FIG. 1) the identification number read from the credit card with the 
identification number inserted by the customer and outputs a signal to the 
minicomputer 38 indicating whether a match has occurred or not. The 
minicomputer 38 in the controller 28 checks the amount of the available 
balance and other data to determine (block 134) if the credit card is 
valid for use in the item transaction. In case a mismatch in the 
identification number is found or there is a determination that the card 
is invalid for use, the display 56 in the terminal device 20 (FIG. 3) will 
be operated by the minicomputer 38 to indicate such a condition requiring 
the terminal device to be operated by the operator in a cash sale mode in 
a manner to be described hereinafter. 
Assuming that the credit card has been determined valid and that the secret 
identification number inserted into the card reader 24 by the customer 
coincides with the identification number read from the credit card by such 
reader, the display 56 in the terminal device 20 will display a legend 
indicating this condition existing to the checkout operator. The checkout 
operator, in response to such condition, will then arcuate one of two 
transaction mode keys located in the keyboard 48 of the terminal device 20 
-- either a cash key (block 138--FIG. 1) requiring the presentation of 
cash to complete the sales transaction or a card key (block 140--FIG. 1) 
indicating a credit sales operation. The system checks the state of 
actuation of the cash key (block 142) and of the card key (block 144) to 
see if either key has been depressed. Upon sensing that the cash key 138 
has been depressed, the system will display and print out on the receipt 
and journal record (block 146--FIG. 1) the total of the sales transaction 
which is equal to the money amount due. Upon receiving the amount due from 
the customer, the system then totals the transaction (block 148). If the 
card key 140 has been depressed by the operator, the data read from the 
credit card representing the balance of the amount available for use as 
credit will be checked by the minicomputer 38. The present application is 
directed to such an amount balance magnetically written on the credit card 
and which is available for use within a definite period of time, for 
instance, one month. The limit available is determined according to the 
credit rating, bank deposit or other commercial considerations of the 
customer that may exist. The available amount or limit of purchase is 
written magnetically on the credit card in a manner well known in the art 
effective as of a specified time, example -- beginning of a moth, or at 
the time of the first sale transaction in the month. Subsequent sale 
transactions will each reduce the balance of the available amount 
according to the amount being purchased. The current available balance 
comprises a portion of the data read by the credit card reader 24 upon 
insertion of the credit card into the reader and which balance was 
transmitted to the minicomputer 38 for use as part of the sales 
transaction as described previously. Upon the system sensing the actuation 
of the card key 140, the current available balance is compared (block 
150-FIG. 1) with the total amount due on the sales transaction. Both the 
credit card available balance and the total amount of the sale are then 
displayed (block 152) on the display 56 (FIG. 3) of the terminal device 
20. The total amount of the sale is subtracted from the available balance 
of the customer (block 154), generating a new or current available balance 
which is written on the credit card by the read/write transport 74 of the 
card reader 24. If the total amount of the sale is greater than the credit 
card balance, the difference between the two amounts will be displayed 
(block 146) on the terminal device display 56 (FIG. 3) as the amount due 
from the customer to complete the present sales transaction. In this 
instance the current available balance generated and caused to be written 
by the read/write transport 74 on the credit card will be zero. In a 
similar manner, if the available balance on the credit card is greater 
than the total amount of the present sale, the amount due from the 
customer will be indicated on display 56 as zero. After receiving the 
amount due from the customer when it is required, the sales transaction is 
completed (block 148--FIG. 1) by totalizing the operation, printing the 
data on the receipt and journal and transmitting the data to the store 
controller 28 for further processing that may be required in completing 
the sales transaction -- which may include recording the data of the sale 
on the cassette recorder 34 for the permanent storing thereof. The credit 
card is then ejected from the card reader 24 for return to the customer 
and end the operation. 
While there have been shown and described embodiments of a checkout system 
utilizing a credit card as payment for a sales transaction, it is obvious 
that many modifications and improvements can be made within the scope of 
this invention, such, for example, as the use of an on-line system with an 
account located in a remote bank for the credit source. Other modification 
may include having the selection of a card or cash operation controlled 
solely by operation of the minicomputer or other data processing 
operations. These modifications and improvements are intended to be 
covered by the following claims.