Beverage dispenser including an improved electronic control system

Information

  • Patent Grant
  • 6496752
  • Patent Number
    6,496,752
  • Date Filed
    Monday, January 22, 2001
    23 years ago
  • Date Issued
    Tuesday, December 17, 2002
    22 years ago
Abstract
A beverage dispenser includes an electronic control system for controlling beverage dispenser components. The beverage dispenser components include at least a user interface, a dispensing valve, and a valve interface for regulating the delivery of a beverage from the dispensing valve. The electronic control system includes a microcontroller for monitoring the user interface and for activating the valve interface responsive to user input, thereby regulating the delivery of a beverage from the dispensing valve. The electronic control system further includes a program memory with firmware configured in a state machine system architecture for controlling the microcontroller. The state machine system architecture supports either a non-preemptive or a preemptive multitasking real time operating system. The firmware includes supervisory control firmware, dispenser tasks firmware, and low level drivers firmware.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates o beverage dispensers and, more particularly, but not by way of limitation, to an electronic control system for beverage dispensers that provides a modular, portable implementation.




2. Description of the Related Art




Beverage dispensers typically include an electronic control system that regulates the dispensing of beverages through the control of one or more dispensing valves and pumps associated therewith. The electronic control system further monitors and regulates a refrigeration unit responsible for cooling the beverage, which typically consists of a beverage syrup and a diluent, such as carbonated or plain water. The electronic control system still further monitors and regulates a carbonation system that produces the carbonated water.




Such a control system for beverage dispensers typically includes a distributed, embedded microcontroller hardware and associated firmware that directs the microcontroller hardware in controlling beverage dispenser operation. Illustratively, the microcontroller hardware monitors beverage dispenser input, which consists of dispensing valve switch activation and the like, and, responsive to such input, the microcontroller hardware produces the necessary control output, which consists of activating a dispensing valve to dispense a desired beverage. In addition, the microcontroller hardware monitors beverage dispenser conditions, which consist of frozen cooling fluid size, carbonated water level, and the like, and, responsive to condition changes, the microcontroller hardware produces the necessary control output, which consists of activating or deactivating a compressor of the refrigeration unit or activating or deactivating a pump of the carbonation system.




Current microcontroller hardware and associated firmware, once implemented, operate adequately in controlling beverage dispensers. Unfortunately, the design process that precedes beverage dispenser implementation is unacceptable because each dispenser is a unique, custom piece of equipment, requiring the microcontroller hardware and associated firmware be designed for the specific component configuration of the beverage dispenser. Thus far, there has been no emphasis on the modularity, portability, and design reuse of microcontroller hardware and associated firmware in beverage dispensers, which leads to long design and implementation periods for new beverage dispensers and the inability to alter existing beverage dispenser designs. Moreover, beverage dispenser designs change rapidly such that it is not cost efficient nor time allocation possible to design microcontroller hardware and firmware for each specific beverage dispenser application.




In today's world, it is necessary to produce and market higher quality beverage dispensers in shorter time periods. Thus, the process of designing and implementing high quality, reliable beverage dispensers must be streamlined. Consequently, there is an industry wide need for a flexible, modular, and design portable microcontroller hardware and associated firmware that supports any type of beverage dispenser components.




SUMMARY OF THE INVENTION




In accordance with the present invention, a beverage dispenser includes an electronic control system for controlling beverage dispenser components. The beverage dispenser components include at least a user interface, a dispensing valve, and a valve interface for regulating the delivery of a beverage from the dispensing valve. The user interface includes a lever activated switch, a push button switch, or a keypad switch matrix. The valve interface includes a solenoid operated valve or volumetric valve technology. The dispensing valve includes any suitable pre- or post-mix valve capable of delivering a flow of beverage therefrom.




The electronic control system includes a microcontroller for monitoring the user interface and for activating the valve interface responsive to user input, thereby regulating the delivery of a beverage from the dispensing valve. The electronic control system further includes a program memory with firmware configured in a state machine system architecture for controlling the microcontroller. The state machine system architecture supports either a non-preemptive or a preemptive multitasking real time operating system.




The electronic control system further includes an interface to permit communication with external devices, a device interface that permits the electronic control system to monitor and control a wide variety of devices attached to the beverage dispenser, and a modem to permit communication with remotely located external devices. A power supply furnishes the power levels required by the electronic control system, and a replaceable battery furnishes the power levels required by the electronic control system in the event of a power interruption. A battery controller switches between the power supply and the replaceable battery.




The electronic control system further includes a real time clock and a memory for storing time and date stamped sales, diagnostic, and service information. A refrigeration control interfaces the electronic control system with a refrigeration unit of the beverage dispenser. Similarly, a carbonation control interfaces the electronic control system with a carbonation system of the beverage dispenser.




The firmware includes supervisory control firmware, dispenser tasks firmware, and low level drivers firmware. The dispenser tasks firmware includes state machines that direct the microcontroller during the performance of tasks associated with beverage dispenser operation. The supervisory control firmware calls each state machine of the dispenser tasks firmware and, further, coordinates the activities and communications between each state machine of the dispenser tasks firmware. The low level drivers firmware interfaces the dispenser tasks firmware with the microcontroller, interfaces the dispenser tasks firmware with dedicated peripherals of the microcontroller, and interfaces the microcontroller with the beverage dispenser components.




The electronic control system is flexible, modular, and portable because electronic control system hardware and beverage dispenser components may be changed or added with minimal beverage dispenser redesign. Illustratively, changing electronic control system hardware or beverage dispenser components requires modification of the low level drivers firmware without any corresponding modification of the supervisory control firmware and the dispenser tasks firmware. Similarly, adding electronic control system hardware or beverage dispenser components requires modification of the low level drivers firmware and addition of a dispenser tasks firmware state machine and corresponding modification of the supervisory control firmware without modification of existing dispenser tasks firmware state machines.




Alternatively, changing to a different valve interface requires modification of the low level drivers firmware and substitution of a dispenser tasks firmware state machine associated with the different valve interface without any corresponding modification of the supervisory control firmware and other dispenser tasks firmware state machines. Furthermore, changing ratio control parameters associated with a beverage dispense requires modification of a beverage dispense state machine of the dispenser tasks firmware without any corresponding modification of the supervisory control firmware, the low level drivers firmware, and other dispenser tasks firmware state machines. Similarly, changing a beverage dispense ratio through physical means requires substituting components of the valve interface without any corresponding modification of the supervisory control firmware, the dispenser tasks firmware, and the low level drivers firmware.




It is therefore an object of the present invention to provide a beverage dispenser including a flexible, modular, and portable electronic control system.




It is another object of the present invention to provide an electronic control system, whereby electronic control system hardware and beverage dispenser components may be changed or added with minimal beverage dispenser redesign.




It is still another object of the present invention to provide an electronic control system including a program memory with firmware configured in a state machine system architecture that supports either a non-preemptive or a preemptive multitasking real time operating system.




It is a further object of the present invention to provide an electronic control system including an interface to permit communication with external devices.




It is still a further object of the present invention to provide an electronic control system including a device interface that permits the electronic control system to monitor and control a wide variety of devices attached to the beverage dispenser.




It is even a further object of the present invention to provide an electronic control system including and a modem to permit communication with remotely located external devices.




Still other objects, features, and advantages of the present invention will become evident to those of ordinary skill in the art in light of the following.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a block diagram illustrating an electronic control system for a beverage dispenser.





FIG. 2

is a flow chart illustrating a supervisory control loop for implementing dispenser task state machines utilized in controlling the electronic control system of FIG.


1


.





FIG. 3

is a block diagram illustrating an electronic control system for a beverage dispenser including an external interface.





FIG. 4

is a block diagram illustrating an electronic control system for a beverage dispenser.





FIG. 5

is a flow chart illustrating a supervisory control loop for implementing dispenser task state machines utilized in controlling the electronic control system of FIG.


4


.





FIG. 6

is a flow chart illustrating a keypad state machine of FIG.


5


.





FIG. 7

is a flow chart illustrating a refrigeration state machine of FIG.


5


.





FIG. 8

is a block diagram illustrating a refrigeration unit sensing system for the electronic control system of FIG.


4


.





FIG. 9

is a flow chart illustrating a carbonation state machine of FIG.


5


.





FIG. 10

is a block diagram illustrating a carbonation sensing system for the electronic control system of FIG.


4


.





FIG. 11

is a flow chart illustrating a user interface state machine of FIG.


5


.





FIG. 12

is a flow chart illustrating a dispense state machine of FIG.


5


.





FIG. 13

is a flow chart illustrating an RS-232 interface state machine of FIG.


5


.





FIG. 14

is a flow chart illustrating a device interface state machine of FIG.


5


.





FIG. 15

is a flow chart illustrating a modem interface state machine of FIG.


5


.





FIG. 16

is a flow chart illustrating a dispenser data collection state machine of FIG.


5


.





FIG. 17

is a flow chart illustrating a service monitor state machine of FIG.


5


.











DETAILED DESCRIPTION OF THE PREFEREED EMBODIMENTS




As illustrated in

FIGS. 1 and 2

, an electronic control system


10


for a beverage dispenser includes a microcontroller


11


, a program memory


12


, a user interface


13


, and a valve interface


14


that regulates the flow of beverage to a valve


15


or valves


15


. Although not shown, those of ordinary skill in the art will recognize that the electronic control system


10


is associated with a power supply that delivers the power levels required by the components of the electronic control system


10


. The microcontroller


11


is a standardly available microcontroller selected based upon the computing power necessary to implement the desired beverage dispensing tasks. The program memory


12


is a standardly available memory ordinarily associated with the selected microcontroller and chosen based upon the memory requirements of the beverage dispenser. Although the program memory


12


is illustrated as separate from the microcontroller


11


, those of ordinary skill in the art will recognize that a microcontroller having sufficient memory may be utilized.




The user interface


13


includes any suitable user-interfacing device, such as a lever-activated switch, a push-button switch, or a programmable keypad having multiple push-button switches. The valve interface


14


includes any device capable of regulating the flow of a beverage to the valve


15


or the valves


15


. Beverage in this embodiment includes, but is not limited to, a beverage syrup and a diluent, such as plain water or carbonated water, either pre-mixed or post-mixed at the valve


15


or the valves


15


or the diluent dispensed singularly. The valve interface


14


thus includes a solenoid that merely opens and closes to deliver a beverage or volumetric valve technology that regulates the exact amounts of diluent and beverage syrup delivered to the valve


15


or the valves


15


. The valve


15


or the valves


15


are any suitable pre- or post-mix type dispensing valve capable of delivering a beverage supplied from a beverage source via the valve interface


14


.




The program memory


12


includes supervisory control firmware


16


, dispenser tasks firmware


17


, and low level drivers firmware


18


configured in a state machine system architecture that supports either a non-preemptive or a preemptive multitasking real time operating system to provide the electronic control system


10


with flexibility, modularity, and design portability. The state machine system architecture implemented in the program memory


12


facilitates flexibility and modularity in that it allows for the rapid reconfiguration of an existing beverage dispenser incorporating the electronic control system


10


. Similarly, the state machine system architecture implemented in the program memory


12


facilitates design portability by supporting a rapid development of new beverage dispensers incorporating the electronic control system


10


.




The implementation of a state machine system architecture in the program memory


12


begins with the supervisory control firmware


16


, which is an infinite loop that calls each state machine comprising the dispenser tasks firmware


17


and, further, coordinates the activities and communications between each of the state machines of the dispenser tasks firmware


17


. Upon the application of power to the electronic control system


10


, the supervisory control firmware


16


calls an initialize dispenser routine


19


, which assumes control of the microcontroller


11


. The initialize dispenser routine


19


includes firmware that directs the microcontroller


11


to initialize the beverage dispenser by performing such tasks as initializing microcontroller peripherals, initially deactivating control solenoids, and the like.




After the initialize dispenser routine


19


completes initialization of the beverage dispenser and, thus, relinquishes control of the microcontroller


11


, the supervisory control firmware


16


calls a state machine


20


, which includes firmware that assumes control of the microcontroller


11


and directs the microcontroller


11


in executing dispenser task


1


. In a non-preemptive multitasking real time operating system, the state machine


20


releases control of the microcontroller


11


when there has been no change of state or upon the completion of the next step in the dispenser task


1


, when there has been a change of state. Alternatively, for a preemptive multitasking real time operating system, the state machine


20


releases control of the microcontroller


11


upon the expiration of a preset time period.




The supervisory control firmware


16


then calls a state machine


21


, which includes firmware that assumes control of the microcontroller


11


and directs the microcontroller


11


in executing dispenser task


2


. In a non-preemptive multitasking real time operating system, the state machine


21


releases control of the microcontroller


11


when there has been no change of state or upon the completion of the next step in the dispenser task


2


, when there has been a change of state. For a preemptive multitasking real time operating system, the state machine


21


releases control of the microcontroller


11


upon the expiration of a preset time period.




Once the state machine


21


releases control of the microcontroller


11


, the supervisory control firmware


16


calls a state machine


22


and then each of remaining state machines


23


-N, which includes firmware that assumes control of the microcontroller


11


and directs the microcontroller


11


in executing dispenser tasks


3


-n. Accordingly, when a preceding state machine


20


-N releases control of the microcontroller


11


under either a non-preemptive or preemptive technique, as previously described, the supervisory control firmware


16


calls the following state machine


20


-N, which assumes control of the microcontroller and directs the microcontroller


11


in executing a dispenser task


1


-n. The supervisory control firmware


16


, therefore, systematically and sequentially calls each of the state machines


20


-N, which direct the microcontroller


11


to perform the n number of dispenser tasks necessary for the operation of the beverage dispenser.




In addition to calling each of the state machines


20


-N of the dispenser tasks firmware


17


, the supervisory control firmware


16


coordinates the interaction among each of the state machines


20


-N. Illustratively, if the state machine


25


requires data or input developed when the state machine


22


controls the microcontroller


11


, the supervisory control firmware


16


oversees the transfer of such developed data or input to the state machine


25


. First, the supervisory control firmware


16


regulates the storing of the data or input developed by the state machine


22


in the program memory


12


. The supervisory control firmware


16


provides and then maintains the addressing information required by the state machine


22


to store the developed data or input into a selected memory location of the program memory


12


. Second, when the state machine


25


assumes control of the microcontroller


11


, the supervisory control firmware


16


furnishes the addressing information to the state machine


25


so that the firmware of the state machine


25


can read the developed data or input, which is used in the execution of the dispenser task


6


.




The electronic control system


10


and, thus, a beverage dispenser incorporating the electronic control system


10


may support any number of beverage dispenser tasks, beginning with the beverage dispenser task of controlling the dispensing of a beverage from a valve or valves and including an n number of desired dispenser tasks. In addition to the beverage dispenser task of controlling the dispensing of a beverage from a valve or valves, beverage dispenser tasks include, but are not limited to, controlling a user interface, controlling a valve interface, regulating a refrigeration system and a carbonation system, controlling an external interface, and the like. The dispenser tasks firmware


17


, thus, includes firmware in the form of state machines


20


-N that, when called by the supervisory control firmware


16


, assumes control of the microcontroller


11


and directs the microcontroller


11


to perform the beverage dispenser tasks necessary for the operation of the beverage dispenser. Although one of state machines


20


-N at a time assumes control of the microcontroller


11


to accomplish a beverage dispenser task, those of ordinary skill in the art will recognize that the state machines


20


-N are processed and run concurrently.




The low level drivers firmware


18


furnishes the microcontroller


11


with firmware that interfaces the dispenser tasks firmware


17


with the microcontroller


11


to permit the dispenser tasks firmware


17


to assume control and direct the microcontroller


11


. The low level drivers firmware


18


further interfaces the dispenser tasks firmware


17


with the dedicated peripherals of the microcontroller


11


such as timers, serial ports, capture/compare ports, and the like, which support the development of data and input utilized by the microcontroller


11


in controlling the beverage dispenser. The low level drivers firmware


18


still further interfaces the microcontroller


11


with beverage dispenser components, such as solenoids, relays, and the like, which permit the microcontroller


11


to direct the operation of the beverage dispenser.




An illustration of the electronic control system


10


incorporating a state machine system architecture that directs the microcontroller


11


in controlling a beverage dispenser to dispense a beverage is described herein. After the initialize dispenser routine


19


initializes the beverage dispenser, the supervisory control firmware


16


calls the state machine


20


, which, for example, could contain firmware for monitoring the user interface


13


to determine if a user has requested a beverage dispense. The user requests a beverage dispense through depressing a lever or push-button activated switch of the user interface


13


associated with a desired beverage flavor, such as cola, rootbeer, lemonade, and the like. The depression of the lever or push-button activated switch outputs from the user interface


13


to the microcontroller


11


a dispense signal that indicates a beverage dispense request.




The microcontroller


11


, in a non-preemptive multitasking real time operating system, maintains the state machine


20


in a “wait for dispense signal state” as long as the user interface


13


is not outputting a dispense signal. In the “wait for dispense signal state”, the state machine


20


immediately relinquishes control of the microcontroller


11


upon calling by the supervisory control firmware


16


, which then calls the state machine


21


. Conversely, the receipt of a dispense signal triggers the microcontroller


11


to change the state machine


20


from the “wait for dispense signal state” to a “dispense signal state”. The state machine


20


then relinquishes control of the microcontroller


11


, and the supervisory control firmware


16


calls the state machine


21


.




When the supervisory control firmware


16


next calls the state machine


20


, the microcontroller


11


, in the “dispense signal state”, inputs and processes the dispense signal to identify the dispense signal with the beverage flavor desired by the user. After processing the dispense signal, the microcontroller


11


changes the state machine


20


from the “dispense signal state” to a “save dispense signal state”, whereupon the state machine


20


releases control of the microcontroller


11


, and the supervisory control firmware


16


calls the state machine


21


.




Upon the next calling of the state machine


20


by the supervisory control firmware


16


, the microcontroller


11


stores the dispense signal in the program memory


12


using an address developed by the supervisory control firmware


16


. The microcontroller


11


also changes the state machine


20


from the “save dispense signal state” to the “wait for dispense signal state”. The state machine


20


then relinquishes control of the microcontroller


11


, and the supervisory control firmware


16


calls the state machine


21


.




The microcontroller


11


, in a preemptive multitasking real time operating system, similarly maintains the state machine


20


in a “wait for dispense signal state” while the user interface


13


is not outputting a dispense signal, however, the state machine


20


relinquishes control of the microcontroller


11


immediately upon the expiration of a preset time period. Consequently, as long as the preset time period has not expired, the receipt of a dispense signal triggers the microcontroller


11


to change the state machine


20


from the “wait for dispense signal state” to a “dispense signal state”. The microcontroller


11


, in the “dispense signal state”, inputs and processes the dispense signal to identify the dispense signal with the beverage flavor desired by the user.




After processing the dispense signal, the microcontroller


11


changes the state machine


20


from the “dispense signal state” to a “save dispense signal state” and, further, in the “save dispense signal state”, stores the dispense signal in the program memory


12


using an address developed by the supervisory control firmware


16


. The microcontroller


11


then changes the state machine


20


from the “save dispense signal state” to the “wait for dispense signal state”.




Accordingly, the microcontroller


11


, as long as the preset time period has not expired, either maintains the state machine


20


in the “wait for dispense signal state” or performs the tasks associated with the “dispense signal state” and the “save dispense signal state”. After the expiration of the preset time period, the state machine


20


immediately relinquishes control of the microcontroller


11


. Nevertheless, the state machine


20


returns to the appropriate one of the “wait for dispense signal state”, the “dispense signal state”, or the “save dispense signal state” upon the next calling of the state machine


20


by the supervisory control firmware


16


.




The supervisory control firmware


16


sequentially calls the state machines


20


-N, which perform a specific beverage dispensing task associated therewith. Illustratively, the firmware for the dispenser task


2


of the state machine


21


could be the control of a carbonation system associated with the beverage dispenser. After the state machine


21


relinquishes control of the microcontroller


11


, the supervisory control firmware


16


calls the state machine


22


, which, for example, could contain firmware associated with the control of a refrigeration unit of the beverage dispenser. Once the state machine


22


relinquishes control of the microcontroller


11


, the supervisory control firmware


16


calls the state machine


23


.




The state machine


23


could, for example, contain firmware for directing the microcontroller


11


in the dispenser task of controlling the valve interface


14


to effect a beverage dispense from the valve


15


or an appropriate one of the valves


15


. The microcontroller


11


, in a non-preemptive multitasking real time operating system, maintains the state machine


23


in a “dispense request state” while a user has not accessed the user interface


13


to select the dispensing of a desired beverage. The microcontroller


11


determines whether a user has accessed the user interface


13


to select the dispensing of a desired beverage by reading, using the address developed by the supervisory control firmware


16


, the memory location of the program memory


12


including the stored dispense signal. In the “dispense request state”, the state machine


23


immediately relinquishes control of the microcontroller


11


upon calling by the supervisory control firmware


16


, which then calls the state machine


24


. When a user has accessed the user interface


13


to select the dispensing of a desired beverage, the microcontroller


11


changes the state machine


23


from the “dispense request state” to a “dispense state”. The state machine


23


then relinquishes control of the microcontroller


11


, and the supervisory control firmware


16


calls the state machine


24


.




Upon the next calling of the state machine


23


, the microcontroller


11


, in the “dispense state”, outputs a valve signal that activates the valve interface


14


to effect a dispense of the selected beverage flavor from the valve


15


or an appropriate one of the valves


15


. The microcontroller


11


then changes the state machine


23


from the “dispense state” to a “beverage delivery state”, whereupon the state machine


23


releases control of the microcontroller


11


, and the supervisory control firmware


16


calls the state machine


24


.




The microcontroller


11


outputs a valve signal to control the valve interface


14


during a dispense in accordance with the particular component comprising the valve interface


14


. Illustratively, if the valve interface


14


is a solenoid controlling a premix valve


15


, the microcontroller


11


activates the solenoid, which opens to permit beverage to flow from the valve


15


. Similarly, if the valve interface


14


includes multiple solenoids each controlling a premix valve


15


, the microcontroller


11


activates a solenoid in accordance with the dispense signal, which opens to permit the selected beverage to flow from the appropriate one of the valves


15


.




Alternatively, when the beverage dispenser is of the post-mix type, the valve interface


14


includes a solenoid for controlling the flow of a beverage flavored syrup and a solenoid for controlling the flow of a diluent, such as plain or carbonated water. Accordingly, the microcontroller


11


, responsive to the dispense signal, activates both solenoids, which open to deliver the beverage flavored syrup and the diluent to the valve


15


where the beverage flavored syrup and the diluent combine to form the selected beverage. Similarly, if the valve interface


14


includes multiple solenoids each controlling the flow of a beverage flavored syrup to a valve


15


and multiple solenoids each controlling the flow of diluent to a valve


15


, the microcontroller


11


activates a beverage flavored syrup and diluent solenoid pair in accordance with the dispense signal, which open to deliver the beverage flavored syrup and the diluent to the valve


15


where the beverage flavored syrup and the diluent combine to form the selected beverage.




In a further illustration, the valve interface


14


could include volumetric valve technology well known to those of ordinary skill in the art in which the microcontroller


11


monitors either the diluent flow or the beverage flavored syrup flow to provide a proper ratio between the diluent and the beverage flavored syrup in the dispensed beverage. The firmware associated with the dispensing task


4


as contained in the state machine


23


, directs the microcontroller


11


to monitor the flow of either the diluent or the beverage flavored syrup utilizing a flowmeter contained in a volumetric valve for either the diluent or the beverage flavored syrup. The microcontroller


11


compares the measured flow value of either the diluent or the beverage flavored syrup to a desired amount of the diluent or the beverage flavored syrup contained in the firmware of the state machine


23


. When the actual flow of either the diluent or the beverage flavored syrup equals the desired flow of either the diluent or beverage flavored syrup, the microcontroller


11


outputs a signal to a volumetric valve for either the diluent or the beverage flavored syrup, which injects either the diluent or the beverage flavored syrup into the valve


15


or an appropriate one of the valves


15


where the injected diluent or beverage flavored syrup combines with the already flowing diluent or beverage flavored syrup to form a beverage.




After the next calling of the state machine


23


, the microcontroller


11


, in the “beverage delivery state”, determines whether to deactivate the valve interface


14


, thereby stopping the dispensing of the selected beverage flavor from the valve


15


or an appropriate one of the valves


15


. Illustratively, for a manual beverage dispense request, the microcontroller


11


reads from the program memory


12


the stored dispense signal to determine if the user interface


13


has continued to output a signal, thereby indicating a sustained depression of a lever or push-button activated switch. As long as there is an existing stored dispense signal, the microcontroller


11


maintains the state machine


23


in the “beverage delivery state” to continue activation of the valve interface


14


, and the state machine


23


immediately relinquishes control of the microcontroller


11


to the state machine


24


. Alternatively, when the stored dispense signal ceases, thereby indicating the release of the lever or push-button activated switch, the microcontroller


11


changes the state machine


23


from the “beverage delivery state” to a “beverage cease state” prior to the state machine


23


relinquishing control of the microcontroller


11


to the state machine


24


.




In a further illustration, the microcontroller


11


utilizes a timer to deliver a desired amount of beverage. As long as the timer has not timed out, the microcontroller


11


maintains the state machine


23


in the “beverage delivery state” to continue activation of the valve interface


14


, and the state machine


23


immediately relinquishes control of the microcontroller


11


to the state machine


24


. Alternatively, when the timer times out, the microcontroller


11


changes the state machine


23


from the “beverage delivery state” to a “beverage cease state” prior to the state machine


23


relinquishing control of the microcontroller


11


to the state machine


24


.




With the next calling of the state machine


23


, the microcontroller


11


, in the “beverage cease state”, deactivates the valve interface


14


, thereby stopping the dispensing of the selected beverage flavor from the valve


15


or an appropriate one of the valves


15


. The microcontroller


11


also changes the state machine


23


from the “beverage cease state” to the “dispense request state”. The state machine


23


then relinquishes control of the microcontroller


11


so that the supervisory control firmware


16


can call the remaining state machines


24


-N, which contain other beverage dispenser tasks, as previously described.




In a preemptive multitasking real time operating system, those of ordinary skill in the art will recognize that the state machine


23


in controlling the valve interface


14


to effect a beverage dispense from the valve


15


or an appropriate one of the valves


15


will include the identical state machine steps and associated tasks as previously described, except the state machine


23


relinquishes control of the microcontroller


11


in response to the expiration of a preset time period. Furthermore, it should be understood by those of ordinary skill in the art that the dispenser tasks firmware


17


would include firmware to stop a beverage dispense in the event of a malfunction of either the user interface


13


or the valve interface


14


.




The implementation of a state machine system architecture provides the electronic control system


10


with a flexible, modular, and portable design that permits the employment of the electronic control system


10


with any user interface and valve interface. Illustratively, changing from a lever activated switch to a push-button activated switch requires only modification of the low-level drivers firmware


18


to support a push-button activated switch without any modification of the supervisory control firmware


16


or the dispenser tasks firmware


17


. Furthermore, changing from solenoid technology in the valve interface to volumetric valve technology requires only modification of the low-level drivers firmware


18


to support volumetric valve technology and the substitution in the dispenser tasks firmware


17


of a volumetric valve technology state machine for a solenoid technology state machine without any modification of the remaining state machines in the dispenser tasks firmware


17


or the supervisory control firmware


16


.




Additionally, altering the ratio between the diluent and the beverage flavored syrup to change beverage taste is simplified due to the implementation of a state machine system architecture in the electronic control system


10


. With volumetric valve technology, the volumetric valve technology state machine remains unmodified, while only ratio control parameters are modified. For example, the number of injection strokes for a diluent and/or a beverage flavored syrup piston of a diluent and/or beverage flavored syrup volumetric valve may be changed, thereby altering the ratio between the diluent and the beverage flavored syrup delivered to the valve


15


or the appropriate one of the valves


15


. Furthermore, controlling beverage quality through a physical means is accomplished without changing the volumetric valve technology state machine by merely substituting components with differing characteristics, such as different volumetric valve pistons, different flow washers, different accumulators, and the like.




The implementation of a state machine system architecture provides the electronic control system


10


with a flexible, modular, and portable design that permits the employment of the electronic control system


10


with a re-configured beverage dispenser or a new beverage dispenser without any significant re-design of the electronic control system


10


. The electronic control system


10


is flexible, modular, and portable with respect to a re-configured beverage dispenser and a new beverage dispenser because beverage dispenser components and/or the hardware of the electronic control system


10


, such as the microcontroller


11


, the type of real time operating system, the user interface


13


, the valve interface


14


, and the like, may be updated or added with only minimal changes in the existing supervisory control firmware


16


, dispenser tasks firmware


17


, and/or the low-level drivers firmware


18


.




Illustratively, replacing hardware of the electronic control system


10


, such as the microcontroller


11


, to re-configure an existing beverage dispenser or produce a new beverage dispenser requires only replacement of the existing hardware and a corresponding change in the low-level drivers firmware


18


without any change in the supervisory control firmware


16


or the hardware dispenser tasks firmware


17


as would be required in electronic control systems for beverage dispensers not implemented using a state machine system architecture. Similarly, adding or deleting a dispenser task, such as adding or removing a dispensing valve or a carbonation system, to re-configure an existing beverage dispenser or produce a new beverage dispenser requires only the addition or removal of the beverage dispenser components associated with the dispenser task and a corresponding modification of the supervisory control firmware


16


, the dispenser tasks firmware


17


, and the low-level drivers firmware


18


. The dispenser tasks firmware


17


is modified through the addition or deletion of a state machine including the firmware to control the added or deleted dispenser task, while the supervisory control firmware


16


is modified to call or not call the added or deleted state machine. The low-level drivers firmware


18


is modified by the addition or deletion of firmware that interfaces the added or deleted state machine with the microcontroller


11


and the microcontroller


11


with the added or removed beverage dispenser components associated with the added or deleted dispenser task.




Accordingly, the electronic control system


10


is completely modular in that any dispenser task may be added or deleted without affecting or requiring the modification of unrelated beverage dispenser tasks. Similarly, the electronic control system


10


is completely portable into new beverage dispensers for rapid re-design because the supervisory control firmware


16


and selected dispenser tasks firmware


17


and low-level drivers firmware


18


are merely incorporated into a program memory associated with a microcontroller that provides beverage dispenser control for an electronic control system incorporated into any configuration of beverage dispenser components.




As illustrated in

FIG. 3

, the electronic control system


10


includes the microcontroller


11


, the program memory


12


including a state machine system architecture, the user interface


13


, the valve interface


14


for regulating the valve


15


or the valves


15


, and, further, an RS-232 interface


30


. The electronic control system


10


operates identically as previously described, except, with the inclusion of the RS-232 interface


30


, the dispenser tasks firmware


17


includes a state machine having firmware for directing the microcontroller


11


in its use of the RS-232 30, the supervisory control firmware


16


recognizes and calls the RS-232 interface state machine, and the low-level drivers firmware


18


includes firmware that interfaces the RS-232 interface state machine with the microcontroller


11


and the microcontroller


11


with the RS-232 interface


30


.




The RS-232 interface


30


permits the electronic control system


10


to communicate with external devices such as dispenser service tools, personal computers, laptop computers, and the like. The RS-232 interface


30


specifically provides the serialized signal levels required for the microcontroller


11


to transmit information to and receive information from an external device. For example, the microcontroller


11


may contain DEX, which is a communication protocol designed to permit the interfacing of a service tool and a piece of equipment installed in the field. Although the microcontroller


11


may contain a communication protocol, it still requires an interface that permits connection of the microcontroller


11


to an external device.




The RS-232 interface


30


, therefore, allows an external device to easily retrieve beverage dispensing information collected by the microcontroller


11


and stored in the program memory


12


. The RS-232 interface


30


, further, provides a service technician with the ability to modify the supervisory control firmware


16


, the dispenser tasks firmware


17


, and the low-level drivers firmware


18


without any difficult disassembly of the beverage dispenser to expose the electronic control system


10


to permit the removal of the program memory


12


for either re-installation of firmware or complete replacement. Illustratively, a service technician could connect a service tool to the RS-232 interface


30


, thereby allowing the service technician to read beverage dispensing information collected by the electronic control system


10


. In addition, the service technician could input new firmware directly to the program memory


12


via the microcontroller


11


so that changes to the electronic control system


10


and, thus, the beverage dispenser can be made quickly, easily, and inexpensively.




As illustrated in

FIG. 4

, an electronic control system


50


includes a microcontroller


51


, a power supply


52


, a battery controller


53


, a replaceable battery


54


, a memory


55


, a real time clock


56


, a memory


57


, a keypad switch matrix


58


, an RS-232 interface


59


, a device interface


60


, and a modem


61


. The microcontroller


51


connects to a refrigeration control


62


, a carbonation control


63


, and dispensing valves


64


of a beverage dispenser to control the refrigeration system, the carbonation system, and the dispensing of a beverage, respectively. The microcontroller


51


in this embodiment is any microcontroller suitable to process the tasks required of a beverage dispenser in dispensing beverages.




The electronic control system


50


includes the power supply


52


to furnish the power levels required by the remaining components of the electronic control system


50


. The electronic control system


50


includes the replaceable battery


54


to provide power to the memory


55


and the real time clock


56


in the event power delivered to the beverage dispenser by the power supply


52


is turned off or interrupted. The battery controller


53


connects to the power supply


52


and the replaceable battery


54


to allow switching between the power supply


52


and the replaceable battery


54


. As long as the beverage dispenser is activated such that the power supply


52


receives power from an external source, the battery controller


53


connects the power supply


52


to provide power to the remaining components of the electronic control system


50


. With the power supply


52


delivering power, the battery controller


53


prevents the replaceable battery


54


from supplying power to the memory


55


and the real time clock


56


. However, when the beverage dispenser is deactivated or power from the external power source is interrupted, the battery controller


53


switches from the power supply


52


, which is no longer supplying power, to the replaceable battery


54


. The replaceable battery


54


supplies power to the memory


55


and the real time clock


56


, which require power at all times to provide a non-volatile system memory and system clock, respectively.




The memory


55


, which is a low power SRAM in this embodiment, through either power furnished from the power supply


52


or the replaceable battery


54


provides a non-volatile memory that stores, for later retrieval, time and date stamped sales, diagnostic, and service information for the beverage dispenser collected by the microcontroller


51


. The memory


55


further stores the beverage dispenser set-up and configuration information utilized by the microcontroller


51


in initializing the beverage dispenser prior to beginning dispensing operations.




The real time clock


56


through either power furnished from the power supply


52


or the replaceable battery


54


provides a system clock for the microcontroller


51


. The microcontroller


51


uses the time and date maintained in the real time clock


56


to time and date stamp the sales, diagnostic, and service information collected by the microcontroller


51


during the operation of the beverage dispenser.




The electronic control system


50


includes memory


57


, which in this embodiment is a multiple page in system reprogrammable flash memory, to provide storage for the firmware required by the microcontroller


51


in controlling the tasks of the beverage dispenser. Although memory


57


is depicted in

FIG. 4

as a separate component of the electronic control system


50


, those of ordinary skill in the art will recognize that a microcontroller with sufficient memory could be substituted for the microcontroller


51


and the memory


57


. The configuration of the firmware in the memory


57


is identical to the program memory


12


in that the memory


57


contains a state machine system architecture including supervisory control firmware, dispenser tasks firmware, and low-level drivers firmware that support either a preemptive or non-preemptive multitasking real time operating system. The supervisory control firmware, dispenser tasks firmware, and low-level drivers firmware direct the microcontroller


51


in performing the tasks of the beverage dispenser as described more fully herein with reference to FIG.


5


.




The electronic control system


50


includes a keypad switch matrix


58


to interface with and support a keypad of the beverage dispenser that provides a user interface for the selection of a particular flavored beverage for dispensing from an appropriate one of the dispensing valves


64


. In this embodiment, the keypad is a series of push-button switches arranged in a matrix format, with each push-button switch associated with a beverage flavor, such as cola, orange, lemonade, root beer, and the like. Consequently, the specific position (i.e., the row and column address) of each push-button switch must provide a dispense signal recognizable by the microcontroller


51


as associated with a specific valve of the dispensing valves


64


so that, upon the depression of a push-button switch, the microcontroller


51


will activate the appropriate one of the dispensing valves


64


. The keypad switch matrix


58


thus permits the microcontroller


51


to associate each push-button switch of the keypad with a specific valve of the dispensing valves


64


. Accordingly, the keypad switch matrix


58


permits the use of any variety of keypads because the particular dispensing valve associated with a push-button switch of the keypad may be assigned by the microcontroller


51


utilizing the keypad switch matrix


58


.




The electronic control system


50


includes an RS-232 interface


59


, a device interface


60


, and a modem


61


to furnish the electronic control system


50


with the capability of external communication. The RS-232 interface


59


permits the electronic control system


50


to communicate with external devices such as dispenser service tools, personal computers, laptop computers, and the like. The RS-232 interface


59


specifically provides the serialized signal levels required for the microcontroller


51


to transmit information to and receive information from an external device. For example, the microcontroller


51


may contain DEX, which is a communication protocol designed to permit the interfacing of a service tool and a piece of equipment installed in the field. Although the microcontroller


51


may contain a communication protocol, it still requires an interface that permits connection of the microcontroller


51


to an external device.




The RS-232 interface


59


, therefore, allows an external device to easily retrieve the time and date stamped sales, diagnostic, and service information for the beverage dispenser collected by the microcontroller


51


and stored in the memory


55


. The RS-232 interface


59


, further, provides a service technician with the ability to modify the supervisory control firmware, the dispenser tasks firmware, and the low-level drivers firmware without any difficult disassembly of the beverage dispenser to expose the electronic control system


50


to permit the removal of the memory


57


for either re-installation of firmware or complete replacement. Illustratively, a service technician could connect a service tool to the RS-232 interface


59


, thereby allowing the service technician to read the time and date stamped sales, diagnostic, and service information for the beverage dispenser. In addition, the service technician could input new firmware directly to the memory


57


via the microcontroller


51


so that changes to the electronic control system


50


and, thus, the beverage dispenser can be made quickly, easily, and inexpensively.




The device interface


60


allows the microcontroller


51


to use a communication protocol that permits the electronic control system


50


to monitor and control a wide variety of devices attached thereto, such as coin acceptors, coin and bill changers, bill validators, credit card validators, network connections, and the like. The device interface


60


specifically provides the serialized signal levels required for the microcontroller


51


to transmit information to and receive information from external devices. The device interface


60


, therefore, provides an option wherein the beverage dispenser through the electronic control system


50


can control any number of other devices associated with the food and beverage dispensing service industry.




The modem


61


permits the electronic control system


50


to communicate with remotely located external devices, such as dispenser service tools, personal computers, laptop computers, and the like, utilizing existing phone lines, cellular systems, or satellite based communication systems. The modem


61


specifically provides the serialized signal levels required for the microcontroller


51


to transmit information to and receive information from remotely located external devices. The modem


61


, therefore, allows a remotely located external device to easily retrieve the time and date stamped sales, diagnostic, and service information for the beverage dispenser collected by the microcontroller


51


and stored in the memory


55


. The modem


61


, further, provides a service technician with the ability to modify the supervisory control firmware, the dispenser tasks firmware, and the low-level drivers firmware from a remote location.




The refrigeration control


62


interfaces the electronic control system


50


with the components of a refrigeration unit of the beverage dispenser. Illustratively, the refrigeration control


62


includes the solenoids and/or relays necessary for the microcontroller


51


to activate and deactivate refrigeration unit components, such as a compressor.




The carbonation control


63


interfaces the electronic control system


50


with the components of a carbonation system of the beverage dispenser. Illustratively, the carbonation control


63


includes a pulse width modulated driver, solenoids, or relays necessary for the microcontroller


51


to control carbonation system components, such as a pump.




The dispensing valves


64


in this embodiment each include a solenoid operated valve, a valve employing volumetric technology, or any suitable pre- or post-mix dispensing valve in association with a device capable of regulating the flow of a beverage to the valve. Beverage in this embodiment includes, but is not limited to, a beverage syrup and a diluent, such as plain water or carbonated water, either pre-mixed or post-mixed at an appropriate one of the dispensing valves


64


or the diluent dispensed singularly.




As illustrated in

FIG. 5

, the supervisory control firmware calls an initialize dispenser routine


70


upon the application of power to the electronic control system


50


. After the initialize dispenser routine


70


relinquishes control of the microcontroller


51


, the supervisory control firmware sequentially calls the dispenser tasks firmware, which, in this embodiment, consists of a keypad state machine


71


, a refrigeration state machine


72


, a carbonation state machine


73


, a user interface state machine


74


, a dispense state machine


75


, an RS-232 interface state machine


76


, a device interface state machine


77


, a modem interface state machine


78


, a dispenser data collection state machine


79


, and a service monitor state machine


80


. In sequentially calling the dispenser tasks firmware, the supervisory control firmware operates under either a non-preemptive or a preemptive multitasking real time operating system. Consequently, for a non-preemptive system, a state machine relinquishes control of the microcontroller


51


either when no state change has occurred or upon the completion of a task or tasks associated with a particular state. Alternatively, for a preemptive system, a state machine relinquishes control of the microcontroller


51


upon the expiration of a preset time period. In this embodiment, the supervisory control firmware and the dispenser tasks firmware will be described with respect to a non-preemptive multitasking real time operating system, nevertheless, those of ordinary skill in the art will recognize that, in a preemptive multitasking real time operating system, the steps performed by each state machine will be identical, except that a state machine will relinquish control of the microcontroller


51


upon the expiration of a preset time period.




The initialize dispenser routine


70


includes firmware that directs the microcontroller


51


in initializing the beverage dispenser in preparation for operation. First, the microcontroller


51


initially deactivates all the beverage dispenser controls, such as solenoids, relays, LED's, and the like. Second, the microcontroller


51


initializes microcontroller peripherals, such as serial ports, as well as any necessary microcontroller features, such as internal timers. Third, the microcontroller


51


reads from memory


55


beverage dispenser control information, such as keypad configuration and assignment of beverage flavors to individual push-button switches of the keypad and dispensing valves and beverage flavored syrup and diluent ratios. Finally, the microcontroller


51


sets any LED's to their starting state for the beginning of beverage dispensing operations. Upon the completion of beverage dispenser initialization, the initialize dispenser routine


70


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the keypad state machine


71


, which assumes control of the microcontroller


51


.




As illustrated in

FIG. 6

, the keypad state machine


71


includes an “off” state


81


an “on” state


82


, and a “masked” state


83


. When called by the supervisory control firmware, the keypad state machine


71


sequentially examines each push-button switch of the keypad to determine if a push-button switch has been depressed or released. Illustratively, for a push-button switch of the keypad, the keypad state machine


71


initially begins in the “off” state


81


, and the microcontroller


51


maintains the keypad state machine


71


in the “off” state


81


until it detects the depression of the push-button switch. While in the “off” state


81


, the microcontroller


51


turns “off” the push-button switch in that it ignores input from the push-button switch. As long as the microcontroller


51


has not detected the depression of the push-button switch, the keypad state machine


71


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the refrigeration state machine


72


.




When the microcontroller


51


detects the push-button switch has remained depressed for a time period sufficient to be “on”, it changes the keypad state machine


71


from the “off” state


81


to the “on” state


82


before the keypad state machine


71


relinquishes control of the microcontroller


51


. Upon the next calling of the keypad state machine


71


for the depressed push button switch, the microcontroller


51


, in the “on” state


82


, detects either a push-button switch malfunction or the release of the push-button switch. The microcontroller


51


detects a push-button switch malfunction through a keypad timer that tracks the maximum time period the push-button switch may remain depressed. The microcontroller


51


further develops, in accordance with the depressed push-button switch, a dispense signal conveying dispense information, such as a selected beverage flavor or diluent, any selected additive flavoring, selected cup size, and the like. The microcontroller


51


also stores the dispense signal in the memory


57


using an address developed by the supervisory control firmware. As long as the keypad timer has not expired or the microcontroller


51


has not detected the release of the push-button switch, the microcontroller


51


maintains the keypad state machine


71


in the “on” state


82


, and the keypad state machine


71


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware.




Once the microcontroller


51


detects the push-button switch has been released for a time period sufficient to be “off”, it changes the keypad state machine


71


from the “on” state


82


to the “off” state


81


before the keypad state machine


71


relinquishes control of the microcontroller


51


. Upon the next calling of the keypad state machine


71


for the released push button switch, the microcontroller


51


, in the “off” state


81


, turns “off” the push-button switch and waits for another depression of the push-button switch as previously described. The microcontroller


51


further stores a dispense off signal in the memory


57


using an address developed by the supervisory control firmware before the keypad state machine


71


relinquishes control of the microcontroller


51


. The microcontroller


51


maintains the keypad state machine


71


in the “off” state


81


until it detects the depression of the push-button switch.




If the keypad timer times out before the microcontroller


51


detects the release of the push-button switch, the microcontroller


51


changes the keypad state machine


71


from the “on” state


82


to the “masked” state


83


before the keypad state machine


71


relinquishes control of the microcontroller


51


. Upon the next calling of the keypad state machine


71


for the malfunctioning push button switch, the microcontroller


51


, in the “masked” state


83


, turns “off” the push-button switch as previously described and waits for the release of the push-button switch. The microcontroller


51


further stores a dispense off signal in the memory


57


using an address developed by the supervisory control firmware before the keypad state machine


71


relinquishes control of the microcontroller


51


. As long as the microcontroller


51


has not detected the release of the push-button switch, the microcontroller


51


maintains the keypad state machine


71


in the “masked” state


83


, and the keypad state machine


71


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware. When the microcontroller


51


detects the push-button switch has been released for a time period sufficient to be “off”, it changes the keypad state machine


71


from the “masked” state


83


to the “off” state


81


before the keypad state machine


71


relinquishes control of the microcontroller


51


. Upon the next calling of the keypad state machine


71


for the released push button switch, the microcontroller


51


operates in the “off” state


81


as previously described.




As illustrated in

FIG. 7

, the refrigeration state machine


72


includes an “off” state


90


, an “off timer” state


91


, an “unfrozen probes” state


92


, an “on” state


93


, and a “frozen probes/on timer” state


91


. The refrigeration state machine


72


initially begins in the “off” state


91


, where the microcontroller


51


turns off a compressor for a refrigeration unit of the beverage dispenser and begins an off timer. The microcontroller


51


then changes the refrigeration state machine


72


from the “off” state


90


to the “off timer” state


91


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


.




With the next calling of the refrigeration state machine


72


, the microcontroller


51


, in the “off timer” state


91


, determines whether the off timer has expired. The “off timer” state


91


provides a delay, 5 minutes in this embodiment, between a deactivation of the compressor and a subsequent reactivation to prevent compressor damage due to short cycling. As long as the off timer has not expired, the microcontroller


51


maintains the refrigeration state machine


72


in the “off timer” state


91


, and the refrigeration state machine


72


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware. After the off timer expires, the microcontroller


51


resets the off timer changes the refrigeration state machine


72


from the “off timer” state


91


to the “unfrozen probes” state


92


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


.




Upon the next calling of the refrigeration state machine


72


, the microcontroller


51


, in the “unfrozen probes” state


92


, determines whether the probes


101


and


102


, as illustrated in

FIG. 8

, are both submerged in unfrozen cooling fluid. As long as the probe


102


remains in frozen cooling fluid, the microcontroller


51


maintains the refrigeration state machine


72


in the “unfrozen probes” state


92


, and the refrigeration state machine


72


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware. When the microcontroller


51


determines that both the probes


101


and


102


are submerged in unfrozen cooling fluid, it changes the refrigeration state machine


72


from the “unfrozen probes” state


92


to the “on” state


93


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


.




After the next calling of the refrigeration state machine


72


, the microcontroller


51


, in the “on” state


93


turns on the compressor for the refrigeration unit and begins an on timer. The microcontroller


51


then changes the refrigeration state machine


72


from the “on” state


93


to the “frozen probes/on timer” state


94


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


.




Upon the next calling of the refrigeration state machine


72


, the microcontroller


51


, in the “frozen probes/on timer” state


94


, detects either a compressor malfunction or whether the probes


101


and


102


are both submerged in frozen cooling fluid. The microcontroller


51


detects a compressor malfunction through the on timer, which tracks the maximum time period the compressor may remain activated. As long as the probe


101


remains in unfrozen cooling fluid and the on timer has not expired, the microcontroller


51


maintains the refrigeration state machine


72


in the “frozen probes/on timer” state


94


, and the refrigeration state machine


72


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware.




When the microcontroller


51


determines that both the probes


101


and


102


are submerged in frozen cooling fluid and the on timer has not expired, it resets the on timer and develops a compressor functioning signal, which it stores in the memory


57


using an address developed by the supervisory control firmware. The microcontroller


51


further changes the refrigeration state machine


72


from the “frozen probes/on timer” state


94


to the “off” state


93


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


. With the next calling of the refrigeration state machine


72


, the microcontroller


51


operates in the “off” state


90


as previously described.




Alternatively, if the on timer expires before both the probes


101


and


102


are submerged in frozen cooling fluid, the microcontroller


51


resets the on timer and develops a compressor malfunction signal, which it stores in the memory


57


using an address developed by the supervisory control firmware. The microcontroller


51


then changes the refrigeration state machine


72


from the “frozen probes/on timer” state


94


to the “off” state


93


, whereupon the refrigeration state machine


72


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


. With the next calling of the refrigeration state machine


72


, the microcontroller


51


operates in the “off” state


90


as previously described.




As illustrated in

FIG. 8

, the microcontroller


51


utilizes a pulse or burst signal to monitor the probes


101


and


102


in determining when they reside in either frozen or unfrozen cooling fluid. This improves over prior monitoring systems because a constant voltage monitoring signal facilitates significant plating of impurities contained in the cooling fluid on the probes, whereas a pulse or burst signal reduces or eliminates plating, thereby increasing probe life span.




The microcontroller


51


at I/O ports


97


and


98


outputs a pulse received at probes


101


and


102


, respectively. When the cooling fluid is frozen to the position shown by numeral


105


, the pulses are not attenuated to ground via probe


103


. As a result, the A/D inputs


99


and


100


receive a signal, signifying that the probes


101


and


102


are both submerged in frozen cooling fluid. Alternatively, when the cooling fluid is frozen to the position shown by numeral


104


, the pulses output at I/O ports


97


and


98


are attenuated to ground. As a result, the pulses are not applied at A/D ports


99


and


100


, signifying that both probes


101


and


102


are submerged in unfrozen cooling.




As illustrated in

FIG. 9

, the carbonation state machine


73


includes an “off” state


110


, a “probes in air” state


111


, an “on” state


112


, and a “probes in water/on timer” state


113


. The carbonation state machine


73


initially begins in the “off” state


110


, where the microcontroller


51


turns off a pump for a carbonation system of the beverage dispenser. The microcontroller


51


then changes the carbonation state machine


73


from the “off” state


90


to the “probes in air” state


111


, whereupon the carbonation state machine


73


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the user interface state machine


74


.




Upon the next calling of the carbonation state machine


73


, the microcontroller


51


, in the “probes in air” state


111


, determines whether the probes


121


and


122


, as illustrated in

FIG. 10

, are both exposed to air within a carbonator tank of the carbonation system. As long as the probe


121


remains submerged in water within the carbonator tank, the microcontroller


51


maintains the carbonation state machine


73


in the “probes in air” state


111


, and the carbonation state machine


73


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware. When the microcontroller


51


determines that both the probes


121


and


122


are exposed to air within the carbonator tank, it changes the carbonation state machine


73


from the “probes in air” state


111


to the “on” state


112


, whereupon the carbonation state machine


73


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the user interface state machine


74


.




After the next calling of the carbonation state machine


73


, the microcontroller


51


, in the “on” state


112


turns on the pump for the carbonation system and begins an on timer. The microcontroller


51


then changes the carbonation state machine


73


from the “on” state


112


to the “probes in water/on timer” state


113


, whereupon the carbonation state machine


73


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the user interface state machine


74


.




Upon the next calling of the carbonation state machine


73


, the microcontroller


51


, in the “probes in water/on timer” state


113


, detects either a pump malfunction or whether the probes


121


and


122


are both submerged in water within the carbonator tank. The microcontroller


51


detects a pump malfunction through the on timer, which tracks the maximum time period the pump may remain activated. As long as the probe


122


remains exposed to air within the carbonator tank and the on timer has not expired, the microcontroller


51


maintains the carbonation state machine


73


in the “probes in water/on timer” state


113


, and the carbonation state machine


73


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware.




When the microcontroller


51


determines that both the probes


121


and


122


are submerged in water within the carbonator tank and the on timer has not expired, it resets the on timer and develops a carbonation functioning signal, which it stores in the memory


57


using an address developed by the supervisory control firmware. The microcontroller


51


further changes the carbonation state machine


73


from the “probes in water/on timer” state


113


to the “off” state


110


, whereupon the carbonation state machine


73


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the carbonation state machine


73


. With the next calling of the carbonation state machine


73


, the microcontroller


51


operates in the “off” state


110


as previously described.




Alternatively, if the on timer expires before both the probes


121


and


122


are submerged in water within the carbonator tank, the microcontroller


51


resets the on timer and develops a carbonation malfunction signal, which it stores in the memory


57


using an address developed by the supervisory control firmware. The microcontroller


51


then changes the carbonation state machine


73


from the “probes in water/on timer” state


113


to the “off” state


110


, whereupon the carbonation state machine


73


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the user interface state machine


74


. With the next calling of the carbonation state machine


73


, the microcontroller


51


operates in the “off” state


110


as previously described.




As illustrated in

FIG. 10

, the microcontroller


51


utilizes a pulse or burst signal to monitor the probes


121


and


122


in determining when they reside in either air or water. This improves over prior monitoring systems because a constant voltage monitoring signal facilitates significant plating of impurities contained in the water on the probes, whereas a pulse or burst signal reduces or eliminates plating, thereby increasing probe life span.




The microcontroller


51


at I/O ports


117


and


118


outputs a pulse received at probes


121


and


122


, respectively. When the water level is at the position shown by numeral


125


, the pulses are attenuated to ground via the tank and the probe


123


. As a result, the A/D inputs


119


and


120


receive no signal, signifying that the probes


121


and


122


are both submerged in water. Alternatively, when the water level is at the position shown by numeral


124


, the pulses output at I/O ports


117


and


118


are not attenuated to ground. As a result, the pulses are applied at A/D ports


119


and


120


, signifying that both probes


121


and


122


are exposed to the air.




As illustrated in

FIG. 11

, the supervisory control loop calls the user interface state machine


74


, which assumes control of the microcontroller


51


, once the carbonation state machine


73


relinquishes control of the microcontroller


51


. The user interface state machine


74


begins in an “activate” state


127


, and the microcontroller


51


maintains the user interface state machine


74


in the “activate” state


127


until it detects that a user interface device or devices require activation. A user interface device or devices in this embodiment include LED's; nevertheless, those of ordinary skill in the art will recognize that any device suitable to convey information to a user may be employed. The information conveyed to the user includes the selected beverage flavor or diluent, any selected additive flavoring, selected cup size, error codes, and the like. As long as the microcontroller


51


has not detected that a user interface device or devices require activation, the user interface state machine


74


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the dispense state machine


75


.




The microcontroller


51


detects that a user interface device or devices require activation by, illustratively, reading from the memory


57


, using the address supplied by the supervisory control firmware, a signal or signals developed by the keypad state machine


71


. When the microcontroller


51


detects a dispense signal or signals, it activates the LED's corresponding to the push-button switch or switches or dispensing valve or valves associated with the dispense signal or signals. In a further illustration, the microcontroller


51


reads from the memory


57


, using the addresses supplied by the supervisory control firmware, the signals developed by the refrigeration state machine


72


and the carbonation state machine


73


. When the microcontroller


51


detects the compressor malfunction signal and/or the carbonation malfunction signal, it activates the LED's that inform the user of the particular malfunction. After activating the appropriate user interface device or devices, the microcontroller


51


changes the user interface state machine


73


from the “activate” state


127


to a “deactivate” state


128


, whereupon the user interface state machine


74


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispense state machine


75


.




Upon the next calling of the user interface state machine


73


, the microcontroller


51


, in the “deactivate” state


128


, detects whether an activated user interface device or devices require deactivation. As long as the microcontroller


51


has not detected that an activated user interface device or devices require deactivation, the user interface state machine


74


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the dispense state machine


75


.




The microcontroller


51


detects that a user interface device or devices require activation by, illustratively, reading from the memory


57


, using the address supplied by the supervisory control firmware, a signal or signals developed by the keypad state machine


71


. When the microcontroller


51


detects a dispense off signal or signals, it deactivates the LED's corresponding to the push-button switch or switches or dispensing valve or valves associated with the initially read dispense signal or signals. In a further illustration, the microcontroller


51


reads from the memory


57


, using the addresses supplied by the supervisory control firmware, the signals developed by the refrigeration state machine


72


and the carbonation state machine


73


. When the microcontroller


51


detects the compressor functioning signal and/or the carbonation functioning signal, it deactivates the LED's that inform the user of the particular malfunction. After deactivating the appropriate user interface device or devices, the microcontroller


51


changes the user interface state machine


73


from the “deactivate” state


128


to the “activate” state


127


, whereupon the user interface state machine


74


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispense state machine


75


. With the next calling of the user interface state machine


74


, the microcontroller


51


operates in the “activate” state


127


as previously described.




As illustrated in

FIG. 12

, the dispense state machine


75


, when called by the supervisory control firmware and in response to a beverage dispense request, directs the microcontroller


51


in the delivery of a beverage from a valve of the dispensing valves


64


. The dispense state machine


75


initially begins in a “detect dispense” state


131


, and the microcontroller


51


maintains the dispense state machine


75


in the “detect dispense” state


131


until it detects a beverage dispense request. As long as the microcontroller


51


has not detected a beverage dispense request, the dispense state machine


75


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the RS-232 interface state machine


76


.




The microcontroller


51


detects whether a beverage dispense has been requested by reading from the memory


57


, using the address supplied by the supervisory control firmware, the signal or signals developed by the keypad state machine


71


as previously described. A beverage dispense request occurs when the microcontroller


51


reads from the memory


57


a dispense signal or signals developed by the keypad state machine


71


. In this embodiment, a dispense signal or signals include a dispense of diluent only, which is either plain or carbonated water, or a dispense of a beverage flavored syrup in combination with diluent and, if desired, an additive flavoring, such as cherry or vanilla. A beverage dispense request via a dispense signal or signals developed by the keypad state machine


71


may also include cup size if the beverage dispenser provides preset cup size dispenses.




Alternatively, a service technician may control beverage dispensing through the attachment of a service tool that functions as the keypad state machine


71


in providing a dispense signal or signals stored in the memory


57


by the microcontroller


51


using an address developed by the supervisory control firmware. A beverage dispense request from a service technician includes a dispense of diluent only or a dispense of a beverage flavored syrup in combination with diluent and, if desired, an additive flavoring and, in addition, a dispense of beverage flavored syrup only or additive flavoring only. The electronic control system


50


, thus, makes it extremely easy to test and diagnose beverage dispenser problems because it is unimportant to the electronic control system


50


whether the beverage dispense request is initiated by a user or a service technician through a service tool.




After the detection of a beverage dispense request, the microcontroller


51


changes the dispense state machine


75


from the “detect dispense” state


131


to one of the “dispense delivery” states


132


-


135


, depending upon the type of beverage dispense request. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




When the beverage dispense request was for diluent only, the microcontroller


51


returns to the “dispense delivery” state


132


upon the next calling of the dispense state machine


75


. The microcontroller


51


, in the “dispense delivery” state


132


, activates an appropriate one of the dispensing valves


64


, which dispenses diluent only. After activating an appropriate one of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “dispense delivery” state


132


to the “dispense over” state


136


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




With the next calling of the dispense state machine


75


, the microcontroller


51


, in the “dispense over” state


136


, determines when the activated valve of the dispensing valves


64


should be deactivated, thereby terminating the beverage dispense. As long as the microcontroller


51


determines the activated valve of the dispensing valves


64


does not require deactivation, it maintains the dispense state machine


75


in the “dispense over” state


136


, whereupon the dispense state machine


75


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the RS-232 interface state machine


76


.




In this embodiment, the microcontroller


51


decides when to deactivate an activated valve of the dispensing valves


64


in response to either manual control of the beverage dispenser keypad or a preset beverage dispense volume or time period. During manual control, the microcontroller


51


determines a beverage dispense is completed when the keypad state machine


71


furnishes a dispense off signal or signals associated with the activated valve of the dispensing valves


64


. When the microcontroller


51


detects the dispense off signal or signals, it changes the dispense state machine


75


from the “dispense over” state


136


to the “stop dispense” state


140


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




For a preset beverage dispense volume or time period, the dispense state machine


75


includes a preset beverage dispense command for each type of beverage dispense request. The preset beverage dispense commands each direct the microcontroller


51


to activate an appropriate one of the dispensing valves


64


and to maintain that valve activated for the beverage dispense volume or time period necessary to produce the requested beverage. Illustratively, for a diluent only beverage dispense into a large cup, the microcontroller


51


, under the direction of the appropriate preset beverage dispense command, activates the correct valve of the dispensing valves


64


, which delivers a volume of diluent or diluent for a time period that fills the large cup. Upon the delivery of the correct volume of diluent or the expiration of the preset beverage dispense time period, the microcontroller


51


changes the dispense state machine


75


from the “dispense over” state


136


to the “stop dispense” state


140


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




Upon the next calling of the dispense state machine


75


, the microcontroller


51


, in the “stop dispense” state


140


, deactivates the activated valve of the dispensing valves


64


. After the deactivation of the activated valve of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “stop dispense” state


140


to the “detect dispense” state


131


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


. With the next calling of the dispense state machine


75


, the microcontroller


51


operates in the “detect dispense” state


131


as previously described.




When the beverage dispense request was for a complete beverage, the microcontroller


51


returns to the “dispense delivery” state


133


upon the next calling of the dispense state machine


75


. The microcontroller


51


, in the “dispense delivery” state


133


, activates an appropriate one of the dispensing valves


64


, which dispenses a beverage flavored syrup, a diluent and, if desired, an additive flavoring. After activating an appropriate one of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “dispense delivery” state


133


to the “dispense over” state


137


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




With the next calling of the dispense state machine


75


, the microcontroller


51


, in the “dispense over” state


137


, determines when the activated valve of the dispensing valves


64


should be deactivated, thereby terminating the beverage dispense. As long as the microcontroller


51


determines the activated valve of the dispensing valves


64


does not require deactivation, it maintains the dispense state machine


75


in the “dispense over” state


137


, whereupon the dispense state machine.


75


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the RS-232 interface state machine


76


.




During manual control, once the microcontroller


51


determines the keypad state machine


71


has furnished a dispense off signal or signals associated with the activated valve of the dispensing valves


64


, it changes the dispense state machine


75


from the “dispense over” state


137


to the “stop dispense” state


141


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




For a complete beverage dispense into an extra-large cup, the microcontroller


51


, under the direction of an appropriate preset beverage dispense command, activates the correct valve of the dispensing valves


64


, which delivers a beverage flavored syrup, a diluent and, if desired, an additive flavoring in a volume or for a time period that fills the extra-large cup. Upon the delivery of the correct volume or the expiration of the preset beverage dispense time period, the microcontroller


51


changes the dispense state machine


75


from the “dispense over” state


137


to the “stop dispense” state


141


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




Upon the next calling of the dispense state machine


75


, the microcontroller


51


, in the “stop dispense” state


141


, deactivates the activated valve of the dispensing valves


64


. After the deactivation of the activated valve of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “stop dispense” state


141


to the “detect dispense” state


131


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


. With the next calling of the dispense state machine


75


, the microcontroller


51


operates in the “detect dispense” state


131


as previously described.




When the beverage dispense request is for a beverage flavored syrup only, the microcontroller


51


returns to the “dispense delivery” state


134


upon the next calling of the dispense state machine


75


. The microcontroller


51


, in the “dispense delivery” state


134


, activates an appropriate one of the dispensing valves


64


, which dispenses the beverage flavored syrup only. After activating an appropriate one of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “dispense delivery” state


134


to the “dispense over” state


138


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




With the next calling of the dispense state machine


75


, the microcontroller


51


, in the “dispense over” state


138


, determines when the activated valve of the dispensing valves


64


should be deactivated, thereby terminating the beverage dispense. As long as the microcontroller


51


determines the activated valve of the dispensing valves


64


does not require deactivation, it maintains the dispense state machine


75


in the “dispense over” state


138


, whereupon the dispense state machine


75


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the RS-232 interface state machine


76


.




During manual control, once the microcontroller


51


determines the keypad state machine


71


has furnished a dispense off signal or signals associated with the activated valve of the dispensing valves


64


, it changes the dispense state machine


75


from the “dispense over” state


138


to the “stop dispense” state


142


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




For a beverage flavored syrup only dispense into a medium cup, the microcontroller


51


, under the direction of an appropriate preset beverage dispense command, activates the correct valve of the dispensing valves


64


, which delivers beverage flavored syrup only in a volume or for a time period that fills the medium cup. Upon the delivery of the correct volume or the expiration of the preset beverage dispense time period, the microcontroller


51


changes the dispense state machine


75


from the “dispense over” state


138


to the “stop dispense” state


142


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




Upon the next calling of the dispense state machine


75


, the microcontroller


51


, in the “stop dispense” state


142


, deactivates the activated valve of the dispensing valves


64


. After the deactivation of the activated valve of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “stop dispense” state


142


to the “detect dispense” state


131


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


. With the next calling of the dispense state machine


75


, the microcontroller


51


operates in the “detect dispense” state


131


as previously described.




When the beverage dispense request is for an additive flavoring only, the microcontroller


51


returns to the “dispense delivery” state


135


upon the next calling of the dispense state machine


75


. The microcontroller


51


, in the “dispense delivery” state


134


, activates an appropriate one of the dispensing valves


64


, which dispenses the additive flavoring only. After activating an appropriate one of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “dispense delivery” state


135


to the “dispense over” state


139


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




With the next calling of the dispense state machine


75


, the microcontroller


51


, in the “dispense over” state


139


, determines when the activated valve of the dispensing valves


64


should be deactivated, thereby terminating the beverage dispense. As long as the microcontroller


51


determines the activated valve of the dispensing valves


64


does not require deactivation, it maintains the dispense state machine


75


in the “dispense over” state


139


, whereupon the dispense state machine


75


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the RS-232 interface state machine


76


.




During manual control, once the microcontroller


51


determines the keypad state machine


71


has furnished a dispense off signal or signals associated with the activated valve of the dispensing valves


64


, it changes the dispense state machine


75


from the “dispense over” state


139


to the “stop dispense” state


143


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




For an additive flavoring only dispense into a small cup, the microcontroller


51


, under the direction of an appropriate preset beverage dispense command, activates the correct valve of the dispensing valves


64


, which delivers an additive flavoring only in a volume or for a time period that fills the small cup. Upon the delivery of the correct volume or the expiration of the preset beverage dispense time period, the microcontroller


51


changes the dispense state machine


75


from the “dispense over” state


139


to the “stop dispense” state


143


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


.




Upon the next calling of the dispense state machine


75


, the microcontroller


51


, in the “stop dispense” state


143


, deactivates the activated valve of the dispensing valves


64


. After the deactivation of the activated valve of the dispensing valves


64


, the microcontroller


51


changes the dispense state machine


75


from the “stop dispense” state


143


to the “detect dispense” state


131


. The dispense state machine


75


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the RS-232 interface state machine


76


. With the next calling of the dispense state machine


75


, the microcontroller


51


operates in the “detect dispense” state


131


as previously described.




As illustrated in

FIG. 13

, the supervisory control loop calls the RS-232 interface state machine


76


, which assumes control of the microcontroller


51


, once the dispense state machine


75


relinquishes control of the microcontroller


51


. The RS-232 interface state machine


76


begins in a “message” state


150


where the microcontroller


51


determines, utilizing the RS-232 interface


59


, whether an external device, such as a dispenser service tool, a personal computer, a laptop computer, and the like, contains external communication information requiring transmission to the electronic control system


50


. The microcontroller


51


, in the “message state


150


, further determines whether the electronic control system


50


contains beverage dispenser information requiring transmission to an external device. As long as an external device does not contain external communication information requiring transmission or the electronic control system


50


does not contain beverage dispenser information requiring transmission, the RS-232 interface state machine


76


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the device interface state machine


77


.




When the microcontroller


51


determines an external device contains external communication information requiring transmission to the electronic control system


50


, it changes the RS-232 interface state machine


76


from the “message” state


150


to the “receive” state


151


. The RS-232 interface state machine


76


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the device interface state machine


77


.




Upon the next calling of the RS-232 interface state machine


76


, the microcontroller


51


, in the “receive” state


151


, inputs the external communication information via the RS-232 interface and then performs any necessary processing in accordance with the instructions contained in the external communication information. External communication information received from an external device includes, but is not limited to, ratio control parameters, beverage dispenser control information utilized in the process of testing and diagnosing faults in the beverage dispenser, and firmware for modifying or replacing the existing supervisory control firmware, dispenser tasks firmware, or low-level driver's firmware. The microcontroller


51


then changes the RS-232 interface state machine


76


from the “receive” state


151


to the “message” state


150


, whereupon the RS-232 interface state machine


76


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the device interface state machine


77


. With the next calling of the RS-232 interface state machine


76


, the microcontroller


51


operates in the “message” state


150


as previously described.




When the microcontroller


51


determines the electronic control system


50


contains beverage dispenser information requiring transmission to an external device, it changes the RS-232 interface state machine


76


from the “message” state


150


to the “transmit” state


152


. The RS-232 interface state machine


76


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the device interface state machine


77


.




Upon the next calling of the RS-232 interface state machine


76


, the microcontroller


51


, in the “transmit” state


151


, outputs the beverage dispenser information to the external device via the RS-232 interface. Beverage dispenser information includes, but is not limited to, time and date stamped sales, diagnostic, and service information. The microcontroller


51


then changes the RS-232 interface state machine


76


from the “transmit” state


152


to the “message” state


150


, whereupon the RS-232 interface state machine


76


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the device interface state machine


77


. With the next calling of the RS-232 interface state machine


76


, the microcontroller


51


operates in the “message” state


150


as previously described.




As illustrated in

FIG. 14

, the device interface state machine


77


includes firmware that permits the electronic control system


50


, through the microcontroller


51


, to control devices, such as coin acceptors, coin and bill changers, bill validators, credit card validators, network connections, and the like. The device interface state machine


77


begins in a “device message” state


160


where the microcontroller


51


determines, utilizing the device interface


60


, whether the electronic control system


50


has received a communication from a device. The microcontroller


51


, in the “device message” state


160


, further determines whether the electronic control system


50


contains information that requires transmission to a device. As long as the electronic control system


50


has not received a communication from a device or does not contain information that requires transmission, the device interface state machine


77


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the modem interface state machine


78


.




When the microcontroller


51


determines the electronic control system


50


has received a communication from a device, it changes the device interface state machine


77


from the “device message” state


160


to the “receive” state


161


. The device interface state machine


77


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the modem interface state machine


78


.




Upon the next calling of the device interface state machine


77


, the microcontroller


51


, in the “receive” state


161


, inputs the device communication via the device interface


60


and then performs any necessary processing in accordance with the information contained therein. Illustratively, if the device is a coin and bill changer, the microcontroller


51


inputs the information, which would be the denomination of the coin or the bill. After inputting the information, the microcontroller


51


determines the correct change for return by the coin and bill changer. The microcontroller


51


then changes device interface state machine


77


from the “receive” state


161


to the “device message” state


160


, whereupon the device interface state machine


77


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the modem interface state machine


78


. With the next calling of the device interface state machine


77


, the microcontroller


51


operates in the “device message” state


160


as previously described.




When the microcontroller


51


determines the electronic control system


50


contains information that requires transmission to a device, it changes the device interface state machine


77


from the “device message” state


160


to the “transmit” state


162


. The device interface state machine


77


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the modem interface state machine


78


.




Upon the next calling of the device interface state machine


77


, the microcontroller


51


, in the “receive” state


161


, outputs the information to the device via the device interface


60


. Illustratively, if the microcontroller


51


contains correct change information, it transmits, via the device interface


60


, a control signal that directs the coin and bill changer to discharge the correct change. The microcontroller


51


then changes device interface state machine


77


from the “transmit” state


162


to the “device message” state


160


, whereupon the device interface state machine


77


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the modem interface state machine


78


. With the next calling of the device interface state machine


77


, the microcontroller


51


operates in the “device message” state


160


as previously described.




As illustrated in

FIG. 15

, the supervisory control loop calls the modem interface state machine


78


, which assumes control of the microcontroller


51


, once the device interface state machine


77


relinquishes control of the microcontroller


51


. The modem interface state machine


78


begins in a “message” state


170


where the microcontroller


51


determines, utilizing the modem


61


, whether the electronic control system


50


has received external communication information from a remotely located external device, such as a dispenser service tool, a personal computer, a laptop computer, and the like, utilizing existing phone lines, cellular systems, or satellite based communication systems. The microcontroller


51


, in the “message” state


170


, further determines whether the electronic control system


50


contains beverage dispenser information requiring transmission to a remotely located external device. As long as the electronic control system


50


has not received external communication information from a remotely located external device or does not contain beverage dispenser information requiring transmission, the modem interface state machine


78


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the dispenser data collection state machine


79


.




When the microcontroller


51


determines the electronic control system


50


has received external communication information from a remotely located external device, it changes the modem interface state machine


78


from the “message” state


170


to the “receive” state


171


. The modem interface state machine


78


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispenser data collection state machine


79


.




Upon the next calling of the modem interface state machine


78


, the microcontroller


51


, in the “receive” state


171


, inputs the external communication information via the modem interface and then performs any necessary processing in accordance with the instructions contained in the external communication information. External communication information received from a remotely located external device includes, but is not limited to, ratio control parameters, beverage dispenser control information utilized in the process of testing and diagnosing faults in the beverage dispenser, and firmware for modifying or replacing the existing supervisory control firmware, dispenser tasks firmware, or low-level driver's firmware. The microcontroller


51


then changes the modem interface state machine


78


from the “receive” state


171


to the “message” state


170


, whereupon the modem interface state machine


78


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispenser data collection state machine


79


. With the next calling of the modem interface state machine


78


, the microcontroller


51


operates in the “message” state


170


as previously described.




When the microcontroller


51


determines the electronic control system


50


contains beverage dispenser information requiring transmission to a remotely located external device, it changes the modem interface state machine


78


from the “message” state


170


to the “transmit” state


172


. The modem interface state machine


78


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispenser data collection state machine


79


.




Upon the next calling of the modem interface state machine


78


, the microcontroller


51


, in the “transmit” state


171


, outputs the beverage dispenser information to the external device via the modem


61


utilizing existing phone lines, cellular systems, or satellite based communication systems. Beverage dispenser information includes, but is not limited to, time and date stamped sales, diagnostic, and service information. The microcontroller


51


then changes the modem interface state machine


78


from the “transmit” state


172


to the “message” state


170


, whereupon the modem interface state machine


78


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the dispenser data collection state machine


79


. With the next calling of the modem interface state machine


78


, the microcontroller


51


operates in the “message” state


170


as previously described.




As illustrated in

FIG. 16

, the supervisory control loop calls the dispenser data collection state machine


79


, which assumes control of the microcontroller


51


, once the modem interface state machine


78


relinquishes control of the microcontroller


51


. The dispenser data collection state machine


79


begins in an “event” state


180


where the microcontroller


51


determines if a beverage dispenser information collection event has occurred. As long as a beverage dispenser information collection event has not occurred, the dispenser data collection state machine


79


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the service monitor state machine


80


.




A beverage dispenser information collection event occurs when the microcontroller


51


, under the direction of the supervisory control firmware, collects beverage dispenser information during the execution of the dispenser tasks firmware. Illustratively, during a beverage dispense as effected by the dispense state machine


75


, the microcontroller


51


tracks each beverage dispense to ascertain such beverage dispenser information as the frequency a beverage flavor is selected, the volume of each particular beverage flavored syrup dispensed, the volume of each particular additive flavoring dispensed, the volume of diluent dispensed, the number of cups dispensed, and the size of each dispensed cup. In a further illustration, the microcontroller


51


tracks the flow of beverage flavored syrup and additive flavoring to determine when a beverage flavored syrup source or an additive flavoring source requires replacement. Beverage dispenser information, in this embodiment, includes, but is not limited to, time and date stamped sales, diagnostic, and service information, such as the frequency a beverage flavor is selected, the volume of each particular beverage flavored syrup dispensed, the volume of each particular additive flavoring dispensed, the volume of diluent dispensed, the number of cups dispensed, the size of each dispensed cup, whether the ratio between beverage flavored syrup and diluent has changed, whether beverage flavored syrup or additive flavoring sources are empty, whether beverage dispenser errors have occurred, and when a dispenser service tool was last connected or disconnected.




When the microcontroller


51


detects a beverage dispenser information collection event, it changes the dispenser data collection state machine


79


from the “event” state


180


to a “read” state


181


. The dispenser data collection state machine


79


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the service monitor state machine


80


.




Upon the next calling of the dispenser data collection state machine


79


, the microcontroller


51


, in the “read” state


171


, reads the time and date from the real time clock


56


. Once the microcontroller


51


reads the time and date, it changes the dispenser data collection state machine


79


from the “read” state


181


to a “store” state


182


, whereupon the dispenser data collection state machine


79


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the service monitor state machine


80


.




After the next calling of the dispenser data collection state machine


79


, the microcontroller


51


, in the “store” state


171


, stores the collected beverage dispenser information in the memory


55


, including the time and date, using an address developed by the supervisory control firmware. Once the microcontroller


51


stores the collected beverage dispenser information, it changes the dispenser data collection state machine


79


from the “store” state


182


to the “event” state


180


, whereupon the dispenser data collection state machine


79


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the service monitor state machine


80


. With the next calling of the dispenser data collection state machine


79


, the microcontroller


51


operates in the “event” state


180


as previously described.




As illustrated in

FIG. 17

, the supervisory control loop calls the service monitor state machine


80


, which assumes control of the microcontroller


51


, once the dispenser data collection state machine


79


relinquishes control of the microcontroller


51


. The service monitor state machine


80


begins in an “event” state


190


where the microcontroller


51


determines whether a warning must be issued, which is accomplished through either the activation of a suitable warning device, such as an audible or visual alarm or, alternatively, through the transmission of an error signal utilizing the RS-232 interface


59


or the modem


61


as previously described. As long as no warning must be issued, the service monitor state machine


80


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the keypad state machine


71


.




In this embodiment, the microcontroller


51


determines whether a warning must be issued by reading from the memory


55


, using the address supplied by the supervisory control firmware, malfunction signals, such as the compressor malfunction signal, the carbonation malfunction signal, a masked push-button switch signal, a no water flow signal, and the like. Similarly, the microcontroller


51


reads from the memory


55


, using the address supplied by the supervisory control firmware, whether a beverage flavored syrup source or an additive flavoring source requires replacement. When the information read by the microcontroller


51


indicates an error condition, it changes the service monitor state machine


80


from the “event” state


190


to an “enable” state


191


. The service monitor state machine


80


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the keypad state machine


71


.




After the next calling of the service monitor state machine


80


, the microcontroller


51


, in the “enable” state


191


, activates the warning device. Furthermore, the microcontroller


51


could generate an error signal, which it stores in the memory


55


using an address supplied by the supervisory control firmware. The microcontroller


51


later transmits that error signal to an external device under the direction of either the RS-232 interface state machine


76


or the modem interface state machine


78


as previously described. Once the warning device is activated, the microcontroller


51


changes the service monitor state machine


80


from the “enable” state


191


to an “over” state


192


, whereupon the service monitor state machine


80


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the keypad state machine


71


.




Upon the next calling of the service monitor state machine


80


, the microcontroller


51


, in the “over” state


192


, determines whether the warning device requires deactivation and/or the generated error signal should be deleted. As long as the warning device does not need deactivation and/or the generated error signal does not require deletion, the service monitor state machine


80


immediately relinquishes control of the microcontroller


51


upon calling by the supervisory control firmware, which then calls the keypad state machine


71


.




In this embodiment, the microcontroller


51


determines whether the warning device requires deactivation and/or the generated error signal should be deleted by reading from the memory


55


the malfunction signals and whether a beverage flavored syrup source or an additive flavoring source requires replacement. When that information indicates the absence of an error condition, the microcontroller


51


changes the service monitor state machine


80


from the “over” state


192


to an “disable” state


193


. The service monitor state machine


80


then relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the keypad state machine


71


.




After the next calling of the service monitor state machine


80


, the microcontroller


51


, in the “disable” state


193


, deactivates the warning device. Furthermore, the microcontroller


51


deletes the error signal, which it previously had stored in the memory


55


. Once the warning device is deactivated, the microcontroller


51


changes the service monitor state machine


80


from the “disable” state


193


to an “event” state


190


, whereupon the service monitor state machine


80


relinquishes control of the microcontroller


51


, and the supervisory control firmware calls the keypad state machine


71


. With the next calling of the service monitor state machine


80


, the microcontroller


51


operates in the “event” state


190


as previously described.




As explained in the foregoing embodiments, an electronic control system for a beverage dispenser configured according to a state machine system architecture that supports either a non-preemptive or a preemptive multitasking real time operating system provides extreme flexibility, modularity, and design portability. Thus, although the electronic control system for a beverage dispenser has been described in terms of the foregoing embodiments, such description has been for exemplary purposes only and, as will be apparent to those of ordinary skill in the art, many alternatives, equivalents, and variations of varying degrees will fall within the scope of the electronic control system for a beverage dispenser. That scope, accordingly, is not to be limited in any respect by the foregoing embodiments, rather, it is defined only by the claims that follow.



Claims
  • 1. A method of controlling a carbonation system of a beverage dispenser, comprising the steps of:providing a beverage dispenser, comprising: a carbonation system including a liquid level monitoring system, and an electronic control system, comprising: a carbonation control to permit interfacing with the carbonation system, a microcontroller for controlling the carbonation control, and a program memory including a carbonation state machine for controlling the microcontroller, wherein the carbonation state machine includes an off state, a probes exposed state, an on state, and a probes unexposed state; calling the carbonation state machine to assume control of the microcontroller; deactivating in the off state a pump of the carbonation system via the carbonation control; changing the carbonation state machine from the off state to the probes exposed state; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the off state to the probes exposed state; determining in the probes exposed state via the liquid level monitoring system when there is insufficient liquid in the carbonation system; relinquishing control of the microcontroller as long as the carbonation state machine remains in the probes exposed state; changing the carbonation state machine from the probes exposed state to the on state when the liquid level monitoring system registers that there is insufficient liquid in the carbonation system; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the probes exposed state to the on state; activating in the on state the pump of the carbonation system via the carbonation control; changing the carbonation state machine from the on state to the probes unexposed state; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the on state to the probes unexposed state; determining in the probes unexposed state via the liquid level monitoring system when there is sufficient liquid in the carbonation system; relinquishing control of the microcontroller as long as the carbonation state machine remains in the probes unexposed state; changing from the probes unexposed state to the off state when the liquid level monitoring system registers that there is sufficient liquid in the carbonation system or upon the expiration of a preset time period; and relinquishing control of the microcontroller upon the changing of the carbonation state machine from the probes unexposed state to the off state.
  • 2. The method of controlling a carbonation system of a beverage dispenser according to claim 1, further comprising the steps of:activating in the on state an on timer; determining in the probes unexposed state if the on timer has expired; and changing from the probes unexposed state to the off state upon the expiration of the on timer.
  • 3. A method of controlling a carbonation system of a beverage dispenser, comprising the steps of:providing a beverage dispenser, comprising: a carbonation system including a liquid level monitoring system, and an electronic control system, comprising: a carbonation control to permit interfacing with the carbonation system, a microcontroller for controlling the carbonation control, and a program memory including a carbonation state machine for controlling the microcontroller, wherein the carbonation state machine includes an off state, a probes exposed state, an on state, and a probes unexposed state; sequentially calling the carbonation state machine to assume control of the microcontroller; deactivating in the off state a pump of the carbonation system via the carbonation control; changing the carbonation state machine from the off state to the probes exposed state; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the off state to the probes exposed state; determining in the probes exposed state via the liquid level monitoring system when there is insufficient liquid in the carbonation system; relinquishing control of the microcontroller as long as the carbonation state machine remains in the probes exposed state; changing the carbonation state machine from the probes exposed state to the on state when the liquid level monitoring system registers that there is insufficient liquid in the carbonation system; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the probes exposed state to the on state; activating in the on state the pump of the carbonation system via the carbonation control; changing the carbonation state machine from the on state to the probes unexposed state; relinquishing control of the microcontroller upon the changing of the carbonation state machine from the on state to the probes unexposed state; determining in the probes unexposed state via the liquid level monitoring system when there is sufficient liquid in the carbonation system; relinquishing control of the microcontroller as long as the carbonation state machine remains in the probes unexposed state; changing from the probes unexposed state to the off state when the liquid level monitoring system registers that there is sufficient liquid in the carbonation system or upon the expiration of a preset time period; and relinquishing control of the microcontroller upon the changing of the carbonation state machine from the probes unexposed state to the off state.
  • 4. The method of controlling a carbonation system of a beverage dispenser according to claim 3, further comprising the steps of:activating in the on state an on timer; determining in the probes unexposed state if the on timer has expired; and changing from probes unexposed state to the off state upon the expiration of the on timer.
Parent Case Info

This Application is a Div. of Ser. No. 09/575,301 file May 19, 2000 which claims benefit of Prov. No. 60/135,076 filed May 20, 1999.

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4545505 Mueller et al. Oct 1985 A
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5033645 Shannon et al. Jul 1991 A
5178799 Brown et al. Jan 1993 A
5592867 Walsh et al. Jan 1997 A
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Provisional Applications (1)
Number Date Country
60/135076 May 1999 US