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`The remote link unit 30 optionally can have its
`
`own processing unit programmed with various types of
`
`information and also to auto reset to predefined defaults
`
`at the end of a service cycle (with or without auto-reset
`
`5
`
`code input).
`
`In respect to inventory,
`
`these defaults
`
`preferably are the maximum number of items set as present
`in any particular vending slot.
`The defaults also may
`include the various thresholds,
`temperatures, and/or
`
`conditions for alarms and/or particular indications in the
`
`10
`
`later described computer 15. With the local interface 31,
`the service personnel can update the inventory if there is
`
`a discrepancy in any particular individual slot as well as
`
`redefining the other various attributes of the link
`
`controller and/or memory.
`
`15
`
`The remote link unit 30 communicates with the
`
`computer 15 over a network 16.
`
`The network 16 is any sort
`
`of communication system which will allow data from the
`
`remote link unit 30 to be provided to the computer 15.
`
`This includes radio, cellular phone, and other known
`
`20
`
`communication systems. Wireless systems are preferred.
`
`Note that due to the limited data which has to be
`
`transferred on the network 16,
`
`the requirement for the
`
`speed, clarity, and lack of noise for the network is
`
`minimal. Redundant and relatively slow transmittal is
`
`25
`
`acceptable.
`
`The network 16 can be bidirectional, allowing
`
`communication as well from the computer 15 to the remote.
`link unit 30 as well. This would also allow the computer
`
`15 to verify that all the information has in fact been .
`received from the remote link unit 30.
`It would also
`
`30
`
`allow the computer 15 to initiate transmission of data
`
`from the remote link unit 30,
`
`to modify the operation of
`
`the link controller and/or contents of the remote link
`
`unit 30 memory, and to otherwise remotely operate the
`
`35
`
`system 10.
`
`With more sophisticated electronic indication
`
`vending machines,
`
`the bidirectional network 16 could also
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`be utilized to alter the pricing of various commodities.
`
`An example of this would be lowering the cost of coffee at
`
`a particular time as an employee benefit or in order to
`
`get rid of stale inventory.
`
`A further example of this
`
`5
`
`would be to increase the cost of particular items during
`
`periods of high demand and/or low inventory.
`
`A controller 32 is located between the network
`
`16 and the computer 15.
`
`The purpose of this controller 32
`
`is to allow the computer 15 to control the network 16.
`
`In
`
`10
`
`the controller 32
`the particular embodiment disclosed,
`also converts the incoming and outgoing data into a form
`
`transmittable over the network. This currently would be
`
`serial digital data.
`
`15
`
`to a separate alarm indicator 33. This alarm indicator
`
`The controller 32 in addition is interconnected
`
`provides a direct indication of the nature and location of
`
`an incoming alarm. This allows the operator to utilize
`
`the computer 15 for other types of independent processing.
`
`It also provides an alarm indication under circumstances
`
`20
`
`when the computer 15 is off line for whatever reason. Note
`
`in the case of multiple tasking computer,
`
`the alarm
`
`indication could be provided also by a load and stay
`
`resident program that constantly analyzes the incoming
`
`signal for an alarm indication, becoming active upon the
`
`25
`
`receipt thereof. This would also allow for the generation
`
`of a red alarm dot on any screen of the display (for
`
`example a word processing program).
`
`The computer 15 communicates with the controller
`
`32 in order to operate the network 16.
`
`The particular
`
`30
`
`computer 15 disclosed communicates with the controller 32
`
`over an RS-232 serial cable.
`
`In addition,
`
`the computer 15
`
`analyzes the incoming data in order to provide a readout
`
`of the status of the various vending machines which are
`
`interconnected thereto.
`
`If the common signals are coded,
`
`35
`
`decoding would preferably occur before data processing.
`
`Normally,
`
`the computer 15 obtains the data by
`
`polling the remote communicating master units for vending
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`information. As each individual communicating master unit
`
`has its own ID code, it is possible for a single computer
`
`15 to extract this information from multiple vending
`
`locations without confusion.
`
`The computer 15 would
`
`5
`
`normally actively poll or automatically receive data from
`
`the various communicating master units under its control
`
`sequentially at certain set times.
`
`Since all of the
`
`incoming data is in a uniform condition due to the data
`
`acquisition unit 20, a single database with uniform
`
`10
`
`parameters can be utilized no matter what the make or
`
`model of the polled vending machine.
`
`For cost considerations,
`
`the computer 15 could
`
`keep track of the inventory located in a particular
`
`machine by the number of vend cycles for a particular item
`
`15
`
`(for example instead of the remote link unit 30 doing so).
`
`These vend cycles would be cumulatively added within the
`
`computer with the result subtracted from the number
`
`programmed into the machine (normally the maximum number
`
`of that item the machine can contain). This programming
`
`20
`
`could occur automatically (for example upon entering a
`
`particular machine make and model) and/or manually.
`
`The
`
`computer would preferably reset to the number programmed
`
`into the machine on indication of a service call.
`
`The
`
`service person would be under instructions to fill each
`
`25
`
`item to this amount.
`
`The computer would thus track
`
`inventory theoretically. Minor deviances would be
`
`accepted as a cost of this simpler system. Optionally
`these deviances could be tracked, for example by using the
`
`local interface.
`
`one could also use computer or bar coded
`
`30
`
`inventory control to automatically update the number
`
`programmed into the machine to the actual amount of
`
`inventory actually used by service personnel. Under this
`
`system since the computer generates the inventory
`
`requirements,
`
`the computer would update its memory based
`
`35
`
`on the inventory actually ordered by the machine. With
`
`such a system, it would be possible to have the computer
`
`generate an inventory requirement by normal container
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`multiples (for example 24 in the case of pop cans) with
`
`the inventory reflected in the computer updated by such
`
`container multiples.
`
`Ideally,
`
`the computer 15 contains a long term
`
`5
`
`memory into which it archives historical data. This long
`
`term memory allows the operator to track what is occurring
`
`in the vending machines over a period of time. This
`
`allows the operator to determine what is selling and what
`
`is not, where it is selling, when he must rotate the
`
`10
`
`stock,
`
`the maintenance condition of the vending machine,
`
`the problems that any particular vending machine may have
`
`had, and other historical attributes of the vending
`
`machine and its operation.
`
`15.
`
`the above,
`
`includes a data records system 34 and a paging
`
`The particular system disclosed,
`
`in addition to
`
`system 35.
`
`The data records system 34 directly archives
`data from the controller 32 into a record system
`
`independently from the computer 15. This automatically
`
`20
`
`backs up the vending machine status data in the event of
`
`damage to the computer and/or vandalism.
`
`It also provides
`
`for third party acquisition of the data from the vending
`
`machines, for example for a university study on the
`
`purchasing habits of the American public.
`
`25
`
`The paging system 35 directly contacts an
`
`individual at remote locations with the status of the
`
`vending machines, most particularly if an alarm occurs.
`
`This allows an individual who is not on—site of the
`
`computer 15 to be made aware of an alarm condition so that
`
`30
`
`it may be handled. Preferably,
`
`the pager system 35
`
`automatically provides the individual with the location of
`
`the vending machine together with the type of alarm. This
`
`latter allows the individual to selectively ignore a low
`
`inventory alarm while advising him of the seriousness of
`
`35
`I
`
`an intrusion alarm. This prevents the inconvenience to
`the operator of what might otherwise be considered to be
`
`nuisance alarms.
`
`The pager transmitter is preferably
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`-located at the computer 15. This allows a single paging
`
`transmitter to be utilized for an entire vending route.
`
`The above block figure is given by way of
`
`example and it is to be understood that the positioning of
`
`the parts may be changed and/or combined without deviating
`
`from the overall operation disclosed.
`
`FIGURE 4 is an example block diagram of a hard
`
`wired sensing and communication circuit 50 representative
`
`of a complex remote link unit 30 according to the present
`
`invention.
`
`Each remote vending machine shown is equipped
`
`with a sensing and communication circuit 50 in order to
`
`‘monitor the operation of the vending machine and transmit
`
`data packets to the central computer system over a
`
`network.
`
`The sensing and communication circuit 50 shown
`
`includes a plurality of optocouplers 52, which detect the
`
`presence of a 120 volt AC or other power signal within the
`
`vending machine.
`vend event for one item within the machine.
`
`For example, a typical signal could be a
`
`Each
`
`optocoupler has five leads 54, 56, 58, 60 and 62.
`
`In this
`
`case,
`
`the first lead 54 is coupled to the element within
`
`the vending machine at which the application of power is
`
`to be sensed.
`
`The second input lead 56 is connected to a
`
`neutral line. An output lead 58 is coupled to an I/O
`
`point 80.
`
`The lead 58 shown carries a digital logic level
`
`signal that indicates the presence or absence of the 120
`
`volt AC signal on the input lead 54.
`
`The optocoupler 52
`
`itself is powered by a DC voltage supplied on the lead 60
`
`and is coupled to ground by the lead 62.
`
`In a typical
`
`vending machine, all of the motors,
`
`the compressor and
`
`indication lights are powered with the power signal,
`this case 120 volts AC.
`
`Therefore, a plurality of
`
`in
`
`optocouplers 52 are used to monitor the operation of these
`elements.
`
`The sensing and communication circuit 50 also
`
`includes one or more switches 70. These switches
`
`typically are DC.
`
`A typical example would be an out of
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`25'
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`30
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`.-~
`
`units temperature sensor.
`
`In the example given, each
`
`switch includes a lead 72 that is pulled to a logic high
`
`voltage (i.e., +5 volts) by a resistor 74 that is coupled
`
`to the voltage supply (i.e., +V). Closing the switch 70
`
`5
`
`connects the lead 72 to a ground potential through a lead
`
`76.
`
`The lead 72 is coupled to the I/O point 80.
`
`The
`
`example sensing and communication circuit 50 further
`
`includes other sensors,
`
`in this case a temperature sensor
`
`circuit 77, which monitors the temperature of the vending
`
`10
`
`machine.
`
`The temperature sensor 77 provides an output
`
`signal on a lead 78 that is coupled to an input of the I/O
`
`port 80. This temperature circuit 77 provides a logic
`
`high level signal if the temperature within the vending
`
`machine exceeds a predetermined maximum.
`
`A logic low
`
`15
`
`level signal is produced on the lead 78 if the temperature
`
`is below the predetermined maximum.
`
`The example I/O port 80 is coupled to a
`
`microprocessor 84 by a conventional set of bus and control
`
`leads 82.
`
`The I/O point 80 shown includes at least three
`
`20
`
`8-bit registers (not separately shown)
`
`that can be coupled
`
`The
`to the output signals provided by up to 24 sensors.
`status of these sensors is thus determined by reading one
`
`bit of one of the 8-bit registers.
`
`For example, assume
`
`hit two of a register is coupled to an optocoupler sensor
`
`25
`
`that detects when a power 120 volt AC signal is applied to
`
`an "exact change required" light in the vending machine.
`
`By reading bit two,
`
`the microprocessor can tell if exact
`
`change is required. This type of long term or length
`signal is easily detected at a single time.
`other
`
`30
`
`parameters in the vending machine can only be detected by
`
`keeping track of the sensor inputs over time.
`
`For
`
`example, assume bit three of a register in the I/O port is
`
`coupled to an optocoupler that senses when power is
`
`applied to a compressor in the vending machine.
`
`By
`
`35
`
`reading hit three and keeping track of when it is a logic
`
`and when it is a logic zero over a period of time,
`
`the
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`
`microprocessor can determine how many times the compressor
`
`cycles. Excessive cycling indicates a faulty compressor.
`
`Also coupled to the example microprocessor
`
`shown,
`
`through the set of bus and control leads 82 is a
`
`5
`
`nonvolatile random access memory (RAM) 86 and a read only
`
`memory (ROM) 88.
`
`The ROM 88 shown has encoded thereon a
`
`suitable computer program that causes the microprocessor
`
`to read the signals produced by the plurality of sensors
`and transmit the status of the sensors to the central
`
`10
`
`computer 20 as will be described.
`
`The example sensing and communication circuit
`
`also preferably includes a universal asynchronous
`
`receiver/transmitter (UART) 90 and a modem 94.
`
`The UART
`
`90 converts parallel data transmitted on the bus 82 to
`
`15
`
`asynchronous serial data that is in turn transmitted on a
`
`lead 92 to the modem 94 as well as converting serial data
`
`received by the modem 94 to parallel data that can be read
`by the microprocessor 84.
`The modem 94 shown is a 1200
`baud modem that is designed to transmit and receive
`
`20
`
`digital signals using a modulated analog carrier signal
`that is transmitted over a network.
`other transmission
`
`standards could also be utilized. Coupled to the example
`
`modem 94 is a suitable antenna 96 that transmits and
`
`receives signals oven the network.
`
`For ease of
`
`25
`
`programming and compatibility,
`
`the modem 94 shown is a
`
`Hayes compatible and transmits and receives digital data
`
`using a well defined protocol.
`
`other modems and speeds
`
`could also be utilized as well as other communication
`
`techniques.
`
`Programming such a modem will be readily
`
`30
`
`apparent to one of ordinary skill in the computer
`
`8 communications art.
`
`The sensing and communication circuit 50 shown
`
`includes an infrared serial port 100 which is coupled by a
`
`lead 102 to an infrared transmitter 104 and an infrared
`
`35
`
`receiver 106.
`
`The infrared serial point is used to
`
`transmit and receive data from a handheld data entry
`
`terminal carried by a service technician.
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`Additionally,
`
`in this unit a serial jack 108 is
`
`coupled to the lead 102 in order to transmit and receive
`
`data from a handheld data entry terminal that is plugged
`
`directly into the serial jack.
`
`5
`
`Finally, a battery backup circuit 110 can be
`
`used to operate a communication circuit if power to the
`
`vending machine is interrupted.
`
`FIGURE 5 is an example state diagram 150 showing
`
`a plurality of modes in which the example microprocessor
`
`10
`
`that runs the sensing and communication circuit 50 could
`
`operate.
`
`The example microprocessor has at least five
`
`distinct modes:
`
`a control mode 160, a communications mode
`
`190, a service mode 250, an analyze mode 290 and an alarm
`mode 340.
`
`15
`
`Upon powering up of the sensing and
`
`communication circuit, the example microprocessor
`
`immediately enters the control mode 160. Here the
`
`microprocessor polls the modem for a connect signal
`
`once a connect
`received from the central computer system.
`signal is received,
`the microprocessor leaves the control
`
`20
`
`mode and enters the communication mode 190 in order to
`
`transmit and receive data packets to and from the central
`
`computer system.
`
`If there is excessive noise on the '
`
`communication link or the modem detects a disconnect
`
`25
`
`signal,
`
`the microprocessor leaves the communication mode
`
`190 and returns to the control mode 160.
`
`If no signal is received,
`
`the example
`
`microprocessor shown polls the I/O point 80 shown in
`
`FIGURE 4 to determine the status of the plurality of
`
`30
`
`sensors disposed in the vending machine.
`
`If one of the
`
`sensor inputs indicates an alarm condition,
`
`the
`
`microprocessor leaves the control mode and enters an alarm
`mode 340.
`
`35
`
`the alarm condition is critical.
`
`If the alarm is not
`
`In the example alarm mode, it is determined if
`
`critical,
`
`the microprocessor returns to the control mode
`
`and will inform the central computer system of the alarmi
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`condition the next time the central computer system shown
`contacts by a call to the remote vending machine.
`If the
`
`alarm is critical,
`
`the remote vending machine initiates a
`
`call to the central computer system and immediately
`informs it of the alarm condition.
`
`5
`
`Another condition the example microprocessor
`
`looks for (by reading the sensor inputs)
`
`is a service call
`
`made by a service technician. Upon detecting that a
`
`switch disposed in the door of the vending machine has
`
`10
`
`been activated by someone opening the door,
`
`the
`
`'
`
`microprocessor shown waits for a code or predetermined
`
`amount of time for a service technician to enter a
`
`predetermined Personal Identification Number
`
`(PIN).
`
`If
`
`this is entered within the predetermined time,
`
`the
`
`15 ‘ microprocessor leaves the control mode 160 and enters a
`
`sensor mode 250.
`
`In the service mode,
`
`the service
`
`technician could typically enter data regarding the amount
`
`of product added to the machine,
`
`the amount of money
`
`removed from the machine and the amount of change placed
`
`20
`
`in the change maker. Once the example microprocessor
`
`detects that the service call is complete, a check is
`
`preferably made whether the remote vending machine should
`
`initiate a call to or otherwise contact the central
`
`A
`
`25
`
`computer system immediately or should wait until the
`central computer system calls the remote vending machine
`
`in order to inform the central computer that a service
`
`call has been completed.
`
`If the remote vending machine is
`
`instructed to contact the central computer system upon
`
`completion of the service call,
`
`the microprocessor leaves
`
`30
`
`the service mode 250 and enters the communications mode
`
`190. Otherwise,
`
`the microprocessor leaves the service
`
`mode 250 and returns to the control mode 160.
`
`In the example communication mode 190,
`
`the
`
`example microprocessor transmits and receives data packets
`
`35
`
`to and from the central computer system over the network
`
`16. After all the data packets have been sent from the
`
`remote vending machine to the central computer system,
`
`the
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`
`vending machine might query the central computer system to
`
`see if the central computer needs to transmit any data to
`
`the remote vending machine.
`
`If a data packet is received
`
`from the central computer system,
`
`the microprocessor
`
`5
`
`leaves the communication mode 190 and enters an analyze
`mode 290.
`
`In the example analyze mode,
`
`the data packet
`
`shown received is tested to determine the appropriate type
`
`of action the microprocessor should take. Possible
`
`10
`
`actions include transmitting the contents of the
`
`microprocessor's memory, reprogramming the
`
`microprocessor's memory, testing the alarm system,
`
`reprogramming the communications to the central computer
`
`system, and resetting the alarm criteria and/or a set of
`
`15
`
`alarm response bits that define which alarm conditions are
`
`critical. Once the received data packet is analyzed and
`
`the example microprocessor has performed the task required
`
`by the data packet,
`the microprocessor shown leaves the
`analyze mode and returns to the communications mode in
`
`20
`
`order to wait for an additional data packet to be
`
`transmitted.
`
`If the microprocessor was instructed by the
`
`received data packet to test the alarm system,
`
`the
`
`microprocessor leaves the analyze mode 290 and enters the
`
`alarm mode 340.
`
`'
`
`25
`
`FIGURE 6 is an example
`
`flow chart showing in
`
`greater detail the steps that might be taken by the
`
`example microprocessor as it is operating in the control
`mode 160 described above. Starting at a step 162,
`the
`
`microprocessor proceeds to set up the modem in a standard
`
`30
`
`protocol at step 164, a Hayes 1200 baud protocol shown.
`
`In the example,
`
`the data transmitted by the modem is
`
`transmitted using a modulated analog carrier signal over
`
`an ordinary communications medium. As will be described
`
`in this example in further detail below, this is possible
`
`35
`
`because the amount of data transmitted between the remote
`
`vending machine and the central computer system is
`
`relatively small and the data is retransmitted if it is
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`
`not received correctly. Thus,
`
`the present invention is
`
`able to withstand errors that may occur during
`
`transmission and does not require the use of a modem that
`
`is specifically designed for transmitting high speed
`
`5
`
`digital data.
`
`the
`Once the example modem has been set up,
`microprocessor shown then polls the modem for a connect
`
`signal to be generated by a call received from the central
`
`computer over the network at a step 166.
`
`If the connect
`
`10
`
`the modem is instructed to go
`signal has been received,
`"off hook" at a step 170 and the microprocessor enters the
`
`communications mode at a step 172.
`
`If no connect signal
`
`is received,
`
`the example microprocessor reads the I/O port
`
`80 to determine the status of the plurality of sensor
`
`15
`
`inputs at a step 174. At a step 176, it is determined if
`
`an alert condition exists.
`
`In some cases this is
`
`accomplished simply by reading the status of the sensor _
`
`output signals.
`
`For example, if the output signal of the
`
`temperature sensor is a logic 1,
`
`then a temperature alarm.
`
`20
`
`exists. other alarm conditions can be determined by
`
`following the changes in the sensor output signals over
`
`time such as the compressor cycles example described
`
`above.
`
`If an alarm condition exists,
`
`the microprocessor
`
`leaves the control mode and enters the alarm mode at a
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`25
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`step 178.
`
`If no alarm condition is present,
`
`the example
`
`microprocessor reads the status of a switch connected to
`the door of the vending machine at step 180 in order to.
`determine whether the door of the vending machine has been
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`30
`
`opened.
`
`If the door has been opened,
`
`the microprocessor
`
`shown enters a service mode at a step 182.
`
`If the door is
`
`not open,
`
`the microprocessor loops back to step 166 where
`
`the modem is again polled to determine if a connect signal
`has been received.
`
`35
`
`FIGURE 7 is an example flow chart showing the
`
`steps taken by the microprocessor shown when operating in
`
`the communications mode 190. Upon entering the
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`communications mode from the control mode,
`
`the
`
`microprocessor polls the modem to determine if there is
`
`excessive noise or if a carrier is no longer present over
`
`the network at a step 192.
`
`If the answer at step 192 is
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`5
`
`yes,
`
`the microprocessor returns to the control mode at a
`
`step 194. Assuming that the noise on the communications
`
`link is not excessive and the carrier signal is still
`
`present,
`
`the microprocessor polls the modem to determine
`
`if a recognizable signal, a "not acknowledge" (NAK) signal
`
`10
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`shown has been received at step 196. Under the
`communications protocol followed by the remote vending
`
`machines and the central computer system,
`
`the central
`
`computer system indicates to the remote vending machines
`
`that any data packets are to be transmitted by first
`
`15
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`sending the NAK signal.
`
`If no NAK signal is received,
`
`the
`
`microprocessor returns to the control mode at a step 198.
`
`Each data packet to be sent to the central
`
`computer is maintained on a queue within the example
`
`microprocessor's RAM.
`
`Each data packet has generally the
`
`20
`
`same structure. Data packets are differentiated by a
`
`"packet type" byte in the data packet.
`
`FIGURE 11 shows an example structure of the data
`
`packets transmitted between the central computer system
`
`and the remote vending machines in the above example
`
`25
`
`system of figure 4.
`
`Each data packet 360 preferably
`
`begins with a marker byte 362.
`
`The ASCII symbol for a
`
`colon is used for the marker byte shown.
`
`Following the
`
`marker byte shown,
`
`is a packet length byte 364 indicating
`
`the entire length of the data packet excluding the marker
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`30
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`byte.
`
`A pair of bytes 366 indicate the unit ID.
`
`Each
`
`vending machine within the monitoring and communication
`
`system has a unique unit ID.
`
`Following the unit ID bytes
`
`shown is a sequence number byte 368. This byte is
`
`incremental each time a unit transmits a data packet to
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`35
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`the central computer system.
`
`By keeping track of the
`
`sequence number,
`
`the central computer is able to determine
`
`if a data packet has been missed.
`
`Following the sequence
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`number shown is a packet type byte 370, which indicates
`
`the type of data to be transmitted.
`
`It is the packet type
`
`which informs either the central computer or the vending
`
`machine how to interpret the data which follows in a
`
`series of bytes 372.
`
`Following the data,
`
`the data packet
`
`shown includes a pair of checksum bytes 374 that allow the
`
`receiving microprocessor to determine if an error occurred
`
`during transmission of the data packet.
`
`The following
`
`illustrates the sequence of bytes that are inserted into a
`
`specific data section of five types of data packets '
`transmitted between the vending machine and the central
`
`computer.
`
`The type of data packet shown is specified in
`
`the packet type bytes as described above.
`
`The following
`
`example packet types can be used to transmit information
`
`regarding a soft drink vending machine having eight
`
`columns filled with cans of product. Those skilled in the
`
`art will recognize that the data packet types can be
`
`easily modified depending on the particular type of
`
`machine being monitored.
`
`Note that although the example
`
`system utilizes only eight columns, it technically has 23
`
`sensor inputs.
`
`It thus is able to provide data for
`
`inventory items in excess of the eight columns shown.
`
`DATA PACKETS TRANSMITTED FROM THE VENDING
`
`MACHINE TO CENTRAL COMPUTER SYSTEM
`
`TYPE 1
`
`(Illustrates Status of Vending Machine)
`
`Byte Name
`
`Description
`
`A
`
`B1
`B2
`
`B3
`
`C1
`
`C2
`
`C3
`
`C4
`
`value of sensor inputs 0-7
`value of sensor inputs 8-15
`
`value of sensor inputs 16-23
`
`total product in column 1
`
`total product in column 2
`
`total product in column 3
`
`total product in column 4
`
`10
`
`15
`
`20
`
`25
`
`30
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`C5
`
`C6
`
`C7
`
`C8
`
`CP
`
`32
`
`total product in column 5
`
`total product in column 6
`
`total product in column 7
`
`total product in column 8
`
`number of compressor cycles
`
`TYPE 2
`
`(Service Packet)
`
`Byte Name
`
`Description
`
`C1
`
`C2
`
`C3
`
`C4
`
`C5
`
`C6
`
`C7
`
`C8
`
`CARM
`
`CHLF
`
`column 1 product added
`
`column 2 product added
`
`column 3 product added
`
`column 4 product added
`
`column 5 product added
`
`column 6 product added
`
`column 7 product added
`
`column 8 product added
`
`cash removed
`
`change left
`
`TYPE 3
`
`(Alarm Bits)
`
`5
`
`10
`
`15
`
`20
`
`25
`
`OXOOO1
`
`total product level below
`
`criterion
`
`30
`
`0x0O02
`
`column product level below
`
`OXOOO4
`
`Ox0O08
`
`0x0O10
`
`0x0O20
`
`35
`
`criterion
`
`change depleted
`
`temperature limit exceeded
`
`intrusion alarm
`
`.
`
`compressor cycles exceed
`
`criterion
`
`Ox0O40
`
`checksum RAM program area had
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