Auxillary Coin Dispenser With Transaction Data Recording and Transfer Mechanisms

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.

This invention relates to coin dispensing systems and, more particularly, to an auxiliary coin dispenser adapted for use with an existing electronic cash register or point-of-sale terminal and incorporating transaction recording apparatus to support "cash-drawer accounting" procedures.

Automatic coin dispensers substantially enhance the efficiency and accuracy with which retail sales transactions can be handled. Auxiliary coin dispensers which operate in conjunction with conventional electronic cash-registers or point-of-sale terminals accurately vend the number of coins to be returned to the customer based on the register's calculation of the total amount of change due, As a result, the register operator can complete each sales transaction more rapidly and more accurately.

However, conventional automatic coin vendors are incompatible with cash-drawer accounting procedures used in many stores. A cash-drawer accounting system makes each register operator responsible for the amount of currency at the sales station during the operator's shift. Typically, a new operator arrives at the station with a pre-counted collection of currency to be used for making change, and the departing operator empties the cash drawer of the remaining currency left at the end of the concluding shift. The store manager, given the register tape (or the equivalent) indicating the total cash income can verify that the amount of cash turned in at the conclusion of a shift equals the sum of cash income plus the currency originally allocated for making change. Cash-drawer accounting effectively deters petty theft and encourages careful procedures. Unfortunately, since it is typically inconvenient to remove and replace the coins in the sales station's coin dispenser at each operator shift change, the store's management is compelled to choose between the convenience of using coin dispensers and the security of cash-drawer accounting procedures.

In a principal aspect, the present invention takes the form of a cash dispenser which incorporates input means for accepting a sequence of identification codes, each of which identifies and marks the beginning of a new accounting period, typically by identifying a new register operator who will be responsible for the sales station during the next shift. In accordance with the invention, an accumulator in the coin dispenser is initialized to hold zero counts when each new identification code is received, and thereafter accumulates the total amount of coins vended during the current accounting period. When a new code is received and before the accumulator is initialized, its contents are stored in a non-volatile memory unit which stores an accounting record for each accounting period, the record indicating both the identification code associated with the period as well as the amount of coins dispensed during that period. In accordance with a further feature of the invention, data transfer means are employed to communicate the content of the data storage unit to an external utilization device, typically a host computer which uses the stored information to calculate the amount of currency (exclusive of the coins remaining in the coin dispenser) which should have been present at the end of each accounting period.

In the preferred embodiment to be described, the coin dispenser takes the form of an auxiliary unit which is connected via an available interface to a conventional electronic cash register or point-of-sale terminal. A microcontroller is employed to convert the signals received over the interface into electrical signals which operate electromechanical coin ejectors which vend the appropriate number of coins of each denomination, and the microprocessor further maintains an accumulating total of the amount of coins dispensed during the current accounting period.

A new accounting period is begun upon the receipt of an identification code. In the preferred embodiment, this code is supplied by a touch memory device which functions as a "clerk's key" holding a unique code value which identifies the clerk who is given custody of the key. The clerk's key, when placed in contact with a key probe mounted on the dispenser, delivers the identification code to the microcontroller which first stores the total for the prior accounting period in a non-volatile data storage unit, along with the identification code identifying that prior period, and initializes the accumulating total to zero values to begin the new period associated with the incoming code.

In the preferred embodiment, a second touch memory device called the "manager's key" is used to gather the transaction records stored in the data storage unit of each coin dispenser. The manager's key is brought into contact with the key probe, is identified by the microcontroller, and is then loaded with the transaction records stored in the data storage unit. The manager's key is then transported to and read by a host computer which processes the transaction data to produce the accounting reports need to perform cash-drawer accounting procedures.

FIG. 1 is a functional, pictorial view of the preferred embodiment of the invention; and

FIG. 2 is a block schematic diagram of the preferred embodiment.

The embodiment of the invention shown in FIG. 1 is a coin dispensing system adapted for use in a retail store having one or more sales stations. At a first of these stations, a coin dispenser 12 is directly connected to a electronic cash register 14. A second sales station seen in FIG. 1 is provided with a second coin dispenser 16 connected to a point-of-sale terminal 20. The terminal 20 performs the same functions as the cash-register 14, but includes the capability of communicating directly with a host computer 25 via a data link 27. The host computer 25 processes the information generated at the individual cash dispensers using appropriate accounting routines.

The electronic cash register unit 14 is conventional an includes a keyboard 30 for accepting price or product identification information concerning items being purchased, and generates a total amount due value displayed at 32. The keyboard 30 may also be used to enter an amount tendered value displayed in the window 34 from which the amount due value is subtracted, thus yielding a change-due value displayed at 36. This change-due value is communicated over an interface 40 to a microprocessor 50 within the coin dispenser 12.

The coin dispenser 12 further includes a coin storage and vending unit indicated generally at 60 which has a capacity of 1200 coins ($113.00 total value in quarters, dimes, nickels and pennies). Each denomination is held in one or more vertical stacks from which coins are individually rended into an output tray 62 in response to microcontroller-generated commands supplied via the microcontroller output channel indicated at 64 in FIG. 1.

In accordance with the invention, the coin dispenser 12 is adapted to separately record the number of coins vended by each sales clerk during the time that clerk is responsible for the transactions at an assigned sales station. To insure that each clerk's account is properly credited with amounts rended by the coin dispenser during that clerk's shift, and to prevent intentional or accidental identification of the wrong account, each sales clerk is assigned and normally given custody of a uniquely coded key device. This key device, when placed in contact with a key probe 70 accessible from the exterior of the dispenser 12, delivers an identification code signal via the probe 70 which is ultimately stored in a writable transaction memory 80 in the dispenser 12.

The transaction memory 80 stores a plurality of records, each composed of a number of fields containing: (1) the clerk identification code obtained via the probe 70 for a particular sales clerk; (2) a time-of-day value produced by an internal clock 90 indicating time period during which transactions for a particular clerk were recorded; and (3) the number of coins vended for each denomination during that time period.

At the end of each business day, or at the conclusion of some other appropriate period, the records stored in each coin dispenser are communicated to the host computer 25 for processing. When the auxiliary coin dispenser is used with an electronic cash register having no communications capabilities, the information accumulated in each coin dispenser can be conveniently and inexpensively collected by means of a "manager's key" seen at 100 in FIG. 1. The manager's key 100 is placed in contact with the probe 70, and is then loaded with information recorded in the transaction memory 80 under the control of the microcontroller 50. The manager's key is then physically transported to a the host computer 25 and placed in electrical contact with a hand-held probe 125 connected to an available port of the computer 25. The computer 25 accepts the information from the manager key for processing into appropriate accounting reports.

When the coin vending apparatus is used in combination with a point of sale terminal such as the terminal 20 seen in FIG. 2, the information concerning the coin vending transactions may alternatively be sent via a bidirectional serial interface 125 between the dispenser 18 and the terminal 20. Terminal 20 the relays the information via the data link 27 to the central computer 120.

The manager's key 100, the clerk's key 110, as well as the internal transaction memory 80 within each coin dispenser, may be advantageously implemented by means of a "touch memory" device such as the Dallas Semiconductor Model DS1994 touch memory unit manufactured by Dallas Semiconductor Corp., Dallas, Tex. The probe 70 used in the coin dispenser may then be a Model DS9092 panel-mounted probe, and the probe 125 may be a Model DS9092G hand-held probe which includes a connecting cable terminated in a standard RJ-11 jack which may in turn be directly connected to an available RS-232 serial communications port of the computer 120.

The DS1994 touch memory devices used to implement the manager's key 100 and the internal transaction memory 80 stores 4 k bits of information. The touch memory units are encapsulated in a durable stainless steel case whose outer housing forms one terminal (ground) which is insulated from a faceplate forming the other terminal (data) of which connects via a single-wire data pathway to a host device. The DS1994 touch memory device communicates with its host using a serial digital signal having a pulse rate of 16.6 k bits per second and is accordingly able to unload or receive 4 k bits of stored information upon essentially momentary contact with its mating probe. The DS1994 touch memory contains its own internal lithium battery which, due to the low-current-drain SRAM memory components used, is able to retain stored information for more than 10 years. In addition, the DS1994 contains an internal real-time clock/calendar whose time-value registers can be read-from and written-to as part of the touch memory's address space. Accordingly, the time value stored in memory 80 may be obtained from the touch memory device (with its clock/calendar operating as the clock source 90 depicted in FIG. 1), with the time value at the time of clerk log-in being saved in the transaction memory 80 with the remainder of the record for the particular clerk shift as illustrated in FIG. 1.

The clerk's identification key may also take the form of a touch memory unit and is illustrated in FIG. 1 by the key 110 used with the second coin dispenser 18. Because the clerk's key need only contain enough information to identify the clerk, it may be conveniently implemented using the Dallas Semiconductor Model 1992 1 k-bit touch memory, which has the same physical dimensions and uses the same communications protocol as the larger model 1994 4 k bit timer.

The components that make up the coin dispenser are depicted schematically in FIG. 2. The principal components of the dispenser as seen in FIG. 2 are the microcontroller 50, a read-only memory 210 which stores the programs executed by the microcontroller 50, a touch memory unit 220 which provides non-volatile data storage and an internal clock/calendar (used to implement the transaction memory 80 and the clock 90 respectively seen in FIG. 1), a coin vending solenoid control circuit indicated generally at 230, a cash-register interface circuit seen at 240, a external touch memory probe circuit 250, and an audible tone generator 260.

The microcontroller 50 employed in the preferred embodiment shown in FIG. 2 is model 8031, a member of the MCS-51 family of microcontrollers manufactured by Intel Corporation, which uses the read-only memory 220 for program storage. The 8031 incorporates four, bi-directional, 8-bit input/output ports identified as port 0, port 1, port 2 and port 3. When addressing the external read-only memory 220, the high order address bits are delivered by the microcontroller 50 via port 2 and the low order address bits are delivered via port 0 to the address input 272 of the memory 210. Instructions from the memory are read from the data output 273 of memory 220 to the 8-bit port 0 of microcontroller 50.

Port 0 also serves as a data output port which delivers an 8-bit output signal to the latch 280 in the coin-vending solenoid control circuit 230 via a data bus 282. Each bit position in latch 280 controls a coin vending solenoid. For example, the first output bit conductor 282 controls the conductivity of a transistor switch 284 whose transconductive path is serially connected with a solenoid winding 286 and a thermistor 288 between a voltage source and ground. The thermistor 288 protects the remainder of the circuit from excessive currents by exhibiting a higher resistance when it is heated with higher currents. The flyback diode 289 provides a current path for inductive current flow when the transistor 284 turns off. The remaining seven bit positions of the latch 280 are connected to similar solenoid circuits to independently control the 8 coin supply racks holding quarters, dimes nickels and pennies.

The Intel 8031 microprocessor 50 includes a built in UART circuit associated with port 3 to provide bidirectional (multiplexed) series communication capabilities. In the 8031, pins 0 and 1 of port 3 are configurable as serial input and serial output pins respectively, and exchange data with an external electronic cash register or point of sale terminal via a standard RS-232 electrical interface 240 implemented by a model

[Insert model, manufacturer name, and brief description of U12 here].

Port 3 also provides additional single-pin input/output capabilities used to access an internal touch memory 220 and an audible tone generator 260. The single-wire communication to the touch memory 220 takes place via pin 6 of port 3 (which also functions as the external data memory write strobe). The audible tone generator 260 is connected to pin 5 of port 3.

Pin 7 of port 1 is connected to receive and transmit data via the external touch memory probe interface circuit 250 seen in FIG. 2. A pair of diodes 251 and 252 limit the voltage excursions on the conductor 255 which connects pin 6 of port 1 to the panel mounted probe 70 implemented with a model DS9092 probe connector produced by Dallas Semiconductor.

In addition to the port connections described above, the 8031 microprocessor includes several pins, not shown in the drawings, which are connected in conventional ways as follows: The power input pins V.sub.cc and V.sub.ss are energized, at power up time, with +5 volts and ground respectively. The reset input RST is connected via an RC-timing circuit to the power source to which holds the RST terminal high for at least two machine cycles to reset the microcontroller 50 at the time it is powered up, causing it to execute the initialization routine named PWRUP in the assembly language listing as discussed below. The ALE (address latch enable) pin is connected to the lower byte address input latch (not shown) in read only memory 220 and informs that latch when port 0 is presenting the low-order address bytes. The EA pin is held high to inform the processor that an external program memory is to be used. Pins XTAL1 and XTAL2 are connected to an external crystal resonating at 11.059 megahertz (chosen to provide standard data rates of 19,200 baud and downward at the serial port 3).

In order to establish a new accounting period, the person assigned to the sales station uses his or her assigned clerk's key as an electronic identification tag to quickly log-in to a coin dispenser. When the dispenser is first powered on, a single beep is issued by the tone generator 260 to indicate that the dispenser is ready to receive a clerk's key. The operator then touches to clerk's key at the probe 770, and a single beep is issued to signify that the log-in was successful and the station now ready to accept sales transactions. A double beep followed by a single beep asks the operator to attempt the log-in again. When the operator's shift is over, the system is powered down again (by turning OFF the ON/OFF switch) so that, at power up, it is ready to accept the next clerk key identification code. The internal transaction memory 80 (implemented with touch memory 220) can store up to 45 transaction records equivalent to 45 different shifts before the data is gathered. The dispenser issues an audible tone from generator 260 to indicate that the maximum number of shifts have been recorded and the records should be transferred.

When a manager's key is brought into contact with the probe 70 and the transaction records are successfully transferred to the manager's key, four short beeps followed by a long beep are issued by generator 260. Touching the manager's key to the probe 125 connected to the host computer 25 transfers the stored data into the host computer 25 via its serial port.

The instructions stored in the read only memory 220 are assembled from the instructions shown in the assembly language listing which appears at the conclusion of this specification. The instructions for the Intel 8031 microprocessor may be converted into machine executable form using the Intel ASM51 macroassembler and linker/relocator programs, part no. D86ASM51, MCS-51 Assembler for PC XT or AT System, Intel Corporation, Santa Clara, Calif. 95051.

The instructions listed below, with explanatory comments, are divided into sections which be briefly summarized as follows:

A. Serial initialization and coin dispensing routines. The routine PWRUP is called by the hardware machine reset at the time power is applied to the system. After setting initial conditions, it checks the settings of a hardware DIP switch (not shown in the drawings) which is set at installation time to identify the particular electronic cash register or point of sale terminal being used. Based on the switch setting, the program at OPTION executes a jump to the routine appropriate for handling the selected register or terminal. For example, if an external cash register or terminal uses a standard serial interface following the National Semiconductor Corporation's SDL protocol, a lump is made the interface routine entry point NSC (found in section C summarized below).

B. DS1994 touch memory interface routines. The assembly language routines listed in this section handle the information flow between the 8031 microcontroller 50 and the internal touch memory 220 and an external touch memory brought into contact with the probe 70. As seen at beginning of section, the symbolic name EXTDEV is assigned to the register location of pin 6 of port 1 which is connected to the single-wire data line 255 to the probe 70 which in turn establishes the connection to an external touch memory device (manager's key or clerk's key). The symbolic name INTDEV is assigned to the register location of pin 6 of port 3, which connects to the single wire data line to the internal DS1994 touch memory 220 used for non-volatile transaction storage. The symbolic name BUZZER is assigned to the register location of pin 5 of port 3 which connects to the external tone generator 260 which serves as an alarm buzzer. The routine beginning at LOGON identifies external devices brought into contact with probe 70 and branches to ISUSER if the device is classified as a clerk's key. ISUSER records the start time of the user's shift in the transaction memory provided by the internal touch memory 220 and initializes the session's variables. If the touch device brought into contact with the probe 70 is a manager's key, the LOGON routine branches to ISMGR, which copies the data stored in the internal touch memory 220 into the manager's key.

C. NSG and IBM serial interface routines. These routines implement variations of the serial interface between the microcontroller 50 and the external cash register or point of sale terminal (illustrated at 14 and 20 respectively in FIG. 1). By way of example, if the a conventional serial port is selected, the routine beginning at entry point NSC is executed to initialize the serial port which awaits transmission from the connected terminal, which initiates all message traffic. Coin dispensing commands from the connected terminal take the form of a sequence of ASCII characters beginning with the letter "C" or "D" following an ASCII EOT code. If the command letter "C" is received, the numerical characters immediately following are indicative of the amount of change to be dispensed, with the last two numerical characters in the sequence indicating the tens and units values of the change due. The routine CALC calculates the number of quarters, dimes, nickels and pennies to be dispensed to total the fractional dollar amount of the change due. Alternatively, the command letter "D" may be used to prefix 4 numerical characters which directly indicate the number of quarters, dimes, nickels and pennies respectively to be dispensed. The change value message is terminated with an ETX character which is then followed by a check character calculated by exclusive or-ing all of the message characters and the terminating ETK character. A NAK character sent back to the terminal if the received and calculated check characters don't agree (see the routines chkbcc). The coin dispenser returns the status code MYSTS in response to each received command character, with the bit values in MYSTS having the following meaning: bit 0=1 means parity error detected; bit 1=1 if function error detected; bit 2 not used; bit 3=1 if dispensing coins; bit 4=1 if low coin alarm is on; bit 5=1 if change has been dispensed; and bit 6 always on to indicate last byte. The coin dispenser also responds to single status characters received from the connected cash register or point of sale terminal as follows: "c" received cause current MYSTS value to be returned; either "d" or "s" received causes the dispenser to return the number of quarters, dimes, nickels and pennies dispensed in the last cycle; if "f" is received the function error bit 1 in MYSTS is set; if "r" is received, the coins dispensed value is reset (the coins dispensed values must be reset with an "r" command before another coin dispensing cycle can be begun, otherwise the function error bit is set.

D. IBM interface routines. These routines provide an alternative interface to certain IBM electronic cash registers not having conventional RS-232 series ports. This interface routine uses pins 0, 1 and 2 of port 1 as clock, data and mode enable inputs respectively.

E. Centronics parallel interface routines. These routines provide a further alternative interface using port 1 as an 8-bit parallel binary interface.

F. Coin dispenser test routines. These routines for testing the operation of the dispenser are executable by setting the DIP switch (described earlier) so that the appropriate test routine is called on power up.

The assembly language listing for the instructions used in the preferred embodiment and stored, in assembled and linked form, in the read-only memory 210 appear below: