Method for detecting and reporting failures in electronic price lavel systems

Abstract: A method for handling failures in an electronic price label (EPL) system (10) automatically diagnoses failures, and may additionally automatically contact a support system (32). The method includes the steps of transmitting a status request to a communications base station (CBS) (15) and to an EPL (18) by a computer (12), receiving a status reply from the CBS (15) and the EPL (18) by the computer (12), comparing the status message to fault data within a fault data file (26) stored within a storage medium (14) by the computer (12), and determining from the comparison whether a fault in the system (10) has occurred.

Description: The present invention relates to a method for detecting and reporting failures in EPL systems. EPL systems typically include a plurality of EPLs for the various merchandise items in a store. EPLs typically display the price of corresponding merchandise items on store shelves and are typically attached to a rail along the leading edge of the shelves. A store may contain thousands of EPLs to display the prices of the merchandise items. The EPLs are coupled to a computer connected to a storage medium where information about the EPLs is typically maintained in an EPL data file. Price information displayed by the EPLs is obtained from the product look up (PLU) file. Component failures in today's EPL systems are often diagnosed by service technicians. The technicians go to the site of the failure and load and execute diagnostic software, which alerts the technicians of possible causes for the failures. The technicians must then order parts. This method of diagnosing EPL systems is time-consuming and costly. All price changes will have to be stopped during the down time. European Patent Application EP-A-0 396 414 discloses a method of repeatedly sending messages to the units of an EPL system. The units of the EPL system acknowledge these messages with a battery status reply. In case no acknowledgement or a low battery status is replied, the data manager of the EPL system switches to a specific problem state. It is an object of the present invention to provide a method for monitoring for EPL failures and for alerting service technicians of possible causes for the failures so that they can bring replacement parts with them to the site to reduce recovery time and shorten down time. According to the present invention there is provided a method for repeatedly checking for faults in an electronic price label (EPL) system, the EPL system comprising a control computer, a plurality of EPLs and at least one communications base station (CBS) through which the computer is in wireless communication with said plurality of EPLs, the method being characterized by the steps of: repeatedly sending status requests from the computer to various CBSs or EPLs within the EPL system; and utilising the computer firstly to determine, from the nature of the reply to said status requests or the absence of any reply to the status requests, whether a fault has occurred in a CBS or an EPL and secondly to determine the most probable nature of the fault from a plurality of possible predetermined faults through an analysis of said nature of the reply to said status requests or the absence of any reply to the status requests; and if a fault has occurred transmitting an indication of the most probable faulty component and the most probable nature of the fault from the computer to a remote support system. Optionally, the method comprises the step of comparing a received status reply with stored fault data, or with stored system configuration data to determine whether a fault has occurred. Alternatively, certain faults may be determined by the absence of a status reply. One embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:- Fig. 1 is a block diagram of an EPL system; Fig.2 is a block diagram of an EPL module; Fig.3 is a flow diagram illustrating the failure detection and reporting method of the present invention; Fig.4 is a chart of tests performed, purpose of tests, and methods of detection; and Fig.5 is a chart of faults monitored, actions, and recommendations. Referring now to Fig.1, EPL system 10 includes computer 12, storage medium 14, communication base stations (CBSs) 15a-d, CBS power supply 16a-b, electronic price labels (EPLs) 18a-d, display 22, printer 23, communications circuitry 24, and noisemaker 25. Computer 12 executes EPL control software 20 and EPL diagnostic software 30. EPL control software 20 records, schedules, and transmits price changes to EPLs 18a-d through CBSs 15a-d, and receives and analyses status messages from EPLs 18a-d through CBSs 15a-d. These status messages would contain an address identifying the EPL from which they had been sent. EPL control software 20 also maintains and uses EPL data file 28, which contains item information, identification information, item price verifier information, and status information for each of EPLs 18a-d. Computer 12 may include one or more communication ports 31a-b. Storage medium 14 is preferably a fixed disk drive. Storage medium 14 stores fault data file 26, EPL system configuration file 27, and EPL data file 28. EPL system configuration file tells computer 12 how system 10 is configured, i.e., the addresses of EPL system components and their location relative to other components within system 10. CBSs 15a-d are connected together in series by cables 35a-c. Here, only four CBSs are shown. CBSs 15a-d each include one transmit antenna 37 and up to four receive antennas 38 for transmitting and receiving messages between CBSs 15a-d and EPLs 18a-d. One or more of the CBSs may receive power from a single power supply. Here, CBSs 15a-b receive power from CBS power supply 16a, and CBSs 15c-d receive power from CBS power supply 16b. CBSs 15a-d each include CBS circuitry 39 which controls operation of each CBS. In CBSs 15a-d, circuitry 39 maintains memory-based CBS data 41. Within CBSs 15b-d, CBS data 41 contains error rates of communication between CBS 15a and each of the other CBSs 15b-d. Within CBS 15a, CBS data 41 contains error rates of communication between CBS 15a and computer 12. When CBS 15c is designated a master as explained below, CBS data 41 within CBS 15c contains error rates of communication between CBS 15c and computer 12. Excessively high error rates can signal a bad connection in cables 33a-b, or cables 35a-c. CBSs 15a-d also include a low-noise amplifier (LNA) 45 which amplifies signals received by CBS receive antennas 38 so that CBS circuitry 39 can better process the information within those signals. One cause of CBS failure is a failure of LNA 45. To determine whether LNA 45 is faulty (failed or not connected), computer 12 transmits a status message to CBS 15a, CBS 15a transmits the status message to EPL 18a, and EPL 18a transmits a return signal to CBS 15a. If the return signal is not received by computer 12 through CBS 15a, computer 12 determines whether LNA 45 is consuming power above a predetermined minimum power level. If the power level is below the predetermined minimum power level, computer 12 transmits a fault message to support system 32. The types of information logged within CBS data 41 include the number of messages sent to other CBSs and whether the other CBSs responded. CBS data 41 also keeps track of the number of messages sent to the EPLs and if it 'heard' anything of interest or not. CBS 15a is a master CBS and CBSs 15b-d are slave CBSs. CBS 15a communicates directly with computer 12. An alternate master may also be designated. Here, CBS 15c is shown as an alternate master which communicates directly with computer 12 through cable 33b when CBS 15a is down (not working properly), its communication port 31a is down, or when cable 33a between CBS 15a and computer 12 is down. EPL interface software 20 primarily includes data scheduler 34 and CBS manager 36. Data scheduler 34 schedules EPL price change messages to be sent to EPLs 18a-d through CBSs 15a-d. CBS manager 36 schedules the actual transmission of price change messages to EPLs 18a-d and the reception of status messages from EPLs 18a-d for predetermined time slots. EPL diagnostic software 30 automatically monitors EPL system 10 for failures, logs failures in fault data file 26, displays failures on display 22, prints failure reports using printer 23, and reports failures and read faults that have been logged in fault data file 26 by other applications to support system 32 using communication circuitry 24. Storage medium 14 contains fault data file 26 and EPL data file 28. Communication circuitry 24 transmits failure messages generated by EPL diagnostic software 30 to support system 32. Communication circuitry 24 is preferably a modem, but could also include network circuitry, such as a local area network (LAN) or wide area network (WAN) adapter. Support system 32 is preferably a computer system with a modem located at the site of an EPL system vendor or EPL system technician. Noisemaker 25 alerts users of a failure. Noisemaker 25 is preferably coupled to computer 12. Turning now to Fig. 2, EPLs 18a-d each include battery 40, transmit and receive antenna 42, display 46, memory 47, and EPL circuitry 48. Since there is only one antenna 42, if antenna 42 is broken, the EPL is considered broken or lost (not in the store). Battery 40 provides power to EPLs 18a-d. A low battery voltage is one cause for EPL malfunction and failure. Transmit and receive antenna 42 receives price change and status messages from CBS 15a-d. Failure of antenna 42 can cause EPL 18a-d to miss price change requests from EPL control software 20. Transmit and receive antenna 42 transmits responses to price change and status messages to CBS 15a-d. Failure of antenna 42 can prevent EPL control software 20 from verifying that price changes have been received and displayed by EPL 18a-d. Display 46 displays price and possibly additional information. Display 46 is preferably a liquid crystal display and includes glass 49. A failure of display 46, which may include a crack in glass 49, prevents EPL 18a-d from displaying price information to customers. There is a fine wire around the periphery of the glass 49. A continuous loop check on the leads that connect to this wire detect whether the glass 49 is cracked or not. Memory 47 stores price verifier information. Preferably, the price verifier information is a checksum of the displayed price. EPL circuitry 48 controls the internal operation of EPL 18a-d. A failure within circuitry 48 can cause a total failure of EPL 18a-d. Turning now to Fig. 3, the operation of EPL diagnostic software 30 is explained in more detail, beginning with START 60. In step 62, EPL diagnostic software 30 periodically sends an instruction to CBS manager 36 to transmit a status request to CBSs 15a-d and EPLs 18a-d. In step 64, EPL diagnostic software 30 receives status replies from CBS manager 36. In step 66, EPL diagnostic software 30 compares the status message with fault data file 26 and configuration file 27. In step 68, EPL diagnostic software 30 determines from the comparison whether a fault has occurred. If not, then the method returns to step 62. If a fault has been detected, EPL diagnostic software 30 displays the fault condition and a recommendation on display 22. Alternatively, EPL diagnostic software may activate noisemaker 25 or cause a printer to print an error message in step 70. In step 72, EPL diagnostic software 30 notifies store personnel and support system 32 of the problem and sends a support request containing the fault condition and recommendation to support system 32. Notification of support system 32 and store personnel could be in the form of a displayed, printed, or aural message. Preferably, display 22 is used to notify store personnel. The method then returns to step 62 to continue monitoring EPL system 10. Advantageously, EPL diagnostic software 30 provides immediate and automatic notification of critical component failure to store personnel and to EPL technicians. Notification of non-critical components failure may be delayed. EPL diagnostic software 30 performs tests which are listed in Fig. 4. Examples of failures that are monitored and reported by EPL diagnostic software 30 are shown in Fig. 5. When a fault occurs, the fault may be determined by implementing one or more tests. For example, if a CBS test on all of CBSs 15a-d indicates that all of CBSs 15a-d have failed, the failure may have been caused by any one of a plurality of causes, least probable of which are substantially simultaneous failures of CBSs 15a-d. A failure of serial port 31a is one possible cause, therefore, a port test is performed. If serial port 31a has failed, EPL diagnostic software 30 generates a support request which is sent to support system 32 by communication circuitry 24. If serial port 31a has not failed, CBS 15a or cable 33a may have failed. A failure of either prevents messages from reaching CBSs 15b-d. To test this cause, CBS 15c is configured as the master CBS and a CBS test is performed on each CBS 15a-d. If CBS 15a passes the CBS test, then cable 33a is the likely cause of failure. EPL diagnostic software 30 generates a support request which is sent to support system 32 by communication circuitry 24. If CBS 15a does not pass the test, and other CBSs also do not pass the test, a power supply test is performed to determine whether power supply 16a is the cause of the failure. If both CBS 15a and CBS 15b have failed, the power supply test compares the failure of CBSs 15a and 15b to EPL system configuration file 27. Since CBSs 15a and 15b are both powered by power supply 16a, a failure of power supply 16a is the likely cause. EPL diagnostic software 30 generates a support request which is sent to support system 32 by communication circuitry 24. As another example of how the tests in Fig. 4 can be combined to diagnose faults in Fig. 5, suppose that EPL diagnostic software 30 queries EPLs 18a-d and provides a preliminary indication that one or more of EPLs 18a-d are not working or not in system 10. If only one EPL is down, then the EPL is down or the EPL is not listed in EPL data file 28. If a plurality of EPLs 18a-d are down, then one of CBSs 15a-d is probably down since it is not probable that a plurality of EPLs 18a-d would fail substantially simultaneously. A CBS test is performed on the CBS associated with the down EPLs. If the CBS is down, EPL diagnostic software 30 generates a support request which is sent to support system 32 by communication circuitry 24. If the CBS is not down, then only part of the CBS may be down. The transmitter portion of CBS circuitry 39 may be the likely cause. Therefore, a CBS transmit test is performed. If the CBS cannot transmit to its associated EPLs, then EPL diagnostic software 30 generates a support request which is sent to support system 32 by communication circuitry 24. Thus there has been described a method for detecting and reporting failures in EPL systems.

Claims: A method of repeatedly checking for faults in an electronic price label (EPL) system (10), the EPL system comprising a control computer (12), a plurality of EPLs (18) and at least one communications base station (CBS) (15) through which the computer (12) is in wireless communication with said plurality of EPLs (18), the method being characterized by the steps of: repeatedly sending status requests from the computer (12) to various CBSs (15) or EPLs (18) within the EPL system; and utilising the computer (12) firstly to determine, from the nature of the reply to said status requests or the absence of any reply to the status requests, whether a fault has occurred in a CBS (15) or an EPL (18) and secondly to determine the most probable nature of the fault from a plurality of possible predetermined faults through an analysis of said nature of the reply to said status requests or the absence of any reply to the status requests; and if a fault has occurred transmitting an indication of the most probable faulty component and the most probable nature of the fault from the computer (12) to a remote support system (32). A method according to claim 1, characterized by the step of: comparing a received status reply with fault data stored within a storage medium (14) to determine whether a fault has occurred. A method according to claim 1, characterized by the step of: comparing a received status reply with system configuration data within a system configuration file (27) stored within a storage medium (14) to determine whether a fault has occurred. A method according to claim 1, characterized by the step of: transmitting a status message from the computer (12) to an EPL through at least one CBS; transmitting a status reply to the computer from the EPL through the CBS; in the absence of a status reply, determining that a fault has occurred in a component within said at least one CBS. A method according to claim 1, in which the EPL system (10) comprises a plurality of CBSs, a first CBS (15a) being coupled to a first serial port (31a) of the computer by a first cable (33a), characterized in that : in the absence of a status reply from any of the CBSs, a loop test is performed on the first serial port; if the first serial port is operating normally, status requests are transmitted to all the CBSs through an alternative serial port (31b) and an alternative cable (33b); and if status replies are received, determining that the first cable (33a) is faulty. A method according to claim 5, in which the EPL system (10) is provided with a plurality of power supplies, characterized in that : if the one cable (33a) to a first CBS is not faulty, status requests are transmitted to the first CBS, and to a second CBS powered by a different power supply (16b); and if status replies are absent from the first CBS, but status replies are received from the second CBS, determining that the power supply (16a) connected to the first CBS is faulty. A method according to claim 1, characterized by the steps of: monitoring transmit and receive errors by said at least one CBS; saving error rate information in said at least one CBS; transmitting a message to said at least one CBS requesting the error rate information; defining a maximum error rate for a CBS; comparing the current error rate information for said at least one CBS with the defined maximum error rate; and determining whether a fault has occurred in any of the cables (33a-b and 35a-c) coupled to said at least one CBS. A method according to claim 2, in which a fault to be determined comprises at least one of: a faulty battery (40) in an EPL, a crack in the glass (49) of an EPL, a faulty transmit antenna (37) in a CBS, and a faulty low noise amplifier (45) in a CBS. A method according to claim 1, characterized by the steps of: transmitting a status message from the computer to an EPL; and in the absence of a status reply, determining that a fault has occurred in the circuitry (48) within an EPL. A method according to any one of the above claims, characterized by the steps of: transmitting a recommendation for fixing the fault to a support system; and at least one of: displaying a description of the fault on a display (22) coupled to the computer, printing a description of the fault on a printer (23) coupled to the computer, and generating an aural alert.

Inventors: GOODWIN III JOHN COKER, GOODWIN III, JOHN COKER
Applicants: NCR INT INC, NCR INTERNATIONAL INC.
Application year: 1996
Main classification: G06F11
IPC codes: G06F11, G06Q30