Abstract:
A method of displaying temporary information by an electronic price label (EPL) which saves bandwidth and time. The method includes the steps of receiving a message containing second information by the EPL, ceasing display of first information by the EPL, displaying the second information by the EPL, reading the first information from a memory within the EPL by the EPL, and redisplaying the first information by the EPL.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present invention is related to the following commonly assigned and co-pending U.S. application: 
     “Method of Displaying Information By An Electronic Price Label”, filed Dec. 4, 1998, invented by Goodwin, and having a U.S. Pat. No. 6,047,263. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to electronic price label (EPT,) systems, and more specifically to a method of displaying temporary information by an EPL. 
     EPL systems typically include a plurality of EPLs for merchandise items in a transaction establishment. 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 transaction establishment may contain thousands of EPLs to display the prices of the merchandise items. The EPLs are coupled to a central server from where information about the EPLs is typically maintained in an EPL data file. Price information displayed by the EPLs is obtained from a price look-up (PLU) data file and stored within an EPL price change record. 
     EPLs typically include a memory for storing operating information, display information, and instructions. This memory typically includes a plurality of data registers. A typical EPL with an eight-character liquid crystal display requires one data register for storing display information. This information may include price information and promotional information. 
     In order to temporarily change information displayed by an EPL, a message containing the temporary information must be sent to the EPL. Following expiration of the temporary period, a message containing the originally displayed information must be sent to the EPL. In total, two messages containing the originally displayed information must be sent to the EPL, one before the temporary change and one after the temporary change. 
     Therefore, in order to conserve EPL system&#39;s communication bandwidth and change display states faster, it would be desirable to provide a method of displaying temporary information by an EPL which avoids having to send originally displayed information back to an EPL after displaying the temporary information. 
     SUMMARY OF THE INVENTION 
     In accordance with the teachings of the present invention, a method of displaying temporary information by an EPL is provided. 
     The method includes the steps of receiving a message containing second information by the EPL, ceasing display of first information by the EPL, displaying the second information by the EPL, reading the first information from a memory within the EPL by the EPL, and redisplaying the first information by the EPL. 
     It is a feature of the present invention that the first display information is only sent a single time to the EPL. The EPL stores the first information in its memory and obtains the first information from the memory in order to redisplay it. 
     It is accordingly an object of the present invention to provide a method of displaying temporary information by an EPL. 
     It is another object of the present invention to provide a method of displaying temporary information by an EPL which avoids having to send originally displayed information back to an EPL, after displaying the temporary information. 
     It is another object of the present invention to provide a method of displaying temporary information by an EPL which stores both primary and temporary information in the EPL. 
     It is another object of the present invention to conserve EPL system communication bandwidth. 
     It is another object of the present invention to return to a previous display state as quickly as possible. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from the subsequent description of the preferred embodiments and the appended claims, taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 is a block diagram of a transaction processing system; 
     FIG. 2A is a block diagram of first embodiment of an EPL; 
     FIG. 2B is a block diagram of second embodiment of an EPL; 
     FIG. 3A is a flow diagram illustrating a first embodiment of the method of the present invention; and 
     FIG. 3B is a flow diagram illustrating a second embodiment of the method of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, transaction system  10  primarily includes host computer system  12 , point-of-sale (POS) system  14 , and EPL system  16 . Here, components  12  and  14  are shown as separate components that are networked together, but they may also form a single component. Thus, host computer system  12  may be a POS terminal which doubles as a host computer for network of other POS terminals. 
     POS system  14  includes bar code reader  18  and POS terminal  20 . 
     EPL system  16  primarily includes EPLs  22 , host EPL computer  24 , and EPL storage medium  26 . 
     Host EPL computer  24  executes EPL software  30 . To assist with execution of certain tasks performed by EPL software  30 , EPL computer  24  includes a built-in time keeping device, commonly referred to as a system clock, which is synchronized with current time, in order to automatically execute the tasks at their scheduled times. 
     EPL software  30  is responsible for scheduling and transmitting price data from EPL data file  32  to EPLs  22 . EPL software  30  obtains prices in PLU data file  46  as they are entered in input device  40  (immediate processing) or after they have been stored within price look-up (PLU) data file  46 . 
     EPL computer  24  also executes EPL message generating application  34 . EPL message generating application  34  records operator-entered display information and instructions and allows the operator to create messages to EPLs  22 . EPL message generating application  34  passes messages to EPL software  30  for scheduling and transmission. 
     EPL message generating application  34  may be any application which is designed to send and receive messages from EPLs  22 . 
     EPL storage medium  26  stores EPL data file  32 . EPL storage medium  26  and is preferably a fixed disk drive. 
     EPL data file  32  contains EPL identification and price checksum information. Price checksum information is calculated from price information in PLU data file  46 . EPL data file  32  contains current information displayed by EPLs  22 . 
     Input device  40  is preferably a keyboard. 
     Host computer system  12  includes PLU storage medium  44  and transaction server  42 . 
     Transaction server  42  handles price requests from POS terminal  20 . POS terminal  20  sends item identification information to transaction server  42  and transaction server  42  returns the corresponding price from PLU data file  46 . 
     PLU storage medium  44  stores PLU data file  46 . PLU data file  46  is available for distribution to POS terminal  20 . Provision may be made for direct access to PLU data file  46  by bar code reader  18 . 
     Turning now to FIGS.  2 A- 2 B, EPLs  22  each include battery  50 , transmit and receive antenna  52 , display  54 , memory  56 , and control circuitry  58 . 
     Battery  50  provides power to each EPL  22 . 
     Transmit and receive antenna  52  receives and transmits messages to EPL computer  24 . 
     Display  54  displays price and possibly additional information, such as promotional information. Display  54  is preferably a liquid crystal display (LCD). 
     Memory  56  includes a plurality of data registers  60 . Under the present invention, a first portion  62  of memory  56  stores primary display information  64 , and a second portion  66  of memory  56  stores temporary display information  68 . Thus, at least one group of data registers  60  stores temporary display information  68  and the one group includes at least one data register  60 . 
     For example, in an EPL  22  having four data registers, one data register may be added to store temporary display information  68 . 
     As another example, in an EPL  22  having eight data registers, four data registers may be allocated to store temporary display information  68 . The four data registers may be further divided to store first, second, third, and fourth temporary display information  68 . 
     EPL circuitry  58  controls the internal operation of EPLs  22  and includes transceiver circuitry for communicating with EPL computer  24 . 
     In particular, EPL circuitry  58  executes instructions from EPL computer  24  which designate information to be displayed. For example, one such instruction is an instruction to display the temporary display information. 
     FIG. 2B differs from FIG. 2A in that EPL  22  additionally includes timer circuits  76  which signal control circuitry  58  to stop displaying temporary information  68  and return to displaying primary information  64 . Thus, for example, if one data register contains temporary display information  68 , a timer circuit associated with that data register signals control circuitry  58  to stop displaying temporary information  68  and return to displaying the primary information  64 . 
     The embodiment of FIG. 2A requires a message from EPL computer  24  to signal control circuitry  58  to stop displaying temporary display information  68  and to redisplay the primary information  64 . 
     During normal operation, control circuitry  58  receives messages from EPL computer  24 , determines whether the display information in the messages is new primary display information or new temporary display information. Control circuitry  58  examines the message for a flag, command code, or other indication of primary or temporary status. If the display information is new temporary display information, control circuitry  58  determines whether a vacant temporary display group exists. If one does exist, control circuitry  58  stores the new temporary display information in the vacant temporary display group and executes the associated display instructions. If one does not exist, control circuitry  58  determines a temporary display group containing executed display information, replaces the executed display information with the new temporary display information, and executes the associated display instructions for the new temporary display information. 
     In the first embodiment, control circuitry  58  causes display  54  to display the new temporary display information until it receives a cancel message from EPL computer  24 . In response to the cancel message, control circuitry  58  causes display  54  to display the primary display information that display  54  was displaying before displaying the new temporary display information. 
     In the second embodiment, control circuitry  58  causes display  54  to display the new temporary display information and initializes the associated time circuit based upon instructions in the message. Control circuitry  58  causes display  54  to stop displaying the new temporary display information when it receives a timer signal from the associated timer circuit. In response to the timer signal, control circuitry  58  causes display  54  to display the primary display information display  54  was displaying before displaying the new temporary display information. 
     For example, suppose a retailer enters a new item into system  10  and the retailer wishes to display “new item” as primary display information  64  on the EPL  22  assigned to the new item. Later that week, the retailer puts the new item on a one-day special promotion to boost customer awareness. In this case, temporary display information  68  could be “on sale/save 0.40”. After the one-day special promotion has expired, the EPL  22  easily reverts back to displaying primary display information  64 , “new item”. 
     Another example relates to Plan-o-gram compliance. Suppose that after store hours a stocker needs to know how to stock shelves. Primary display information  64  is price information. Temporary display information  68 , such as “01.04|3. 4” for a product, may be sent to an EPL  22  assigned to the product. This means that the product is in section 1, shelf 4, position 3 and has a facing value of 4 (4 wide). After the stocker has read temporary display information  68  and stocked the shelf, a cancel message or timer signal causes primary display information  64  to be displayed. 
     Turning now to FIG. 3A, a temporary display method corresponding to the first embodiment (FIG. 2A) is illustrated in more detail beginning with START  80 . 
     In step  82 , control circuitry  58  waits for a message from FPL computer  24 . If control circuitry  58  receives a message, operation proceeds to step  84 . 
     In step  84 , control circuitry  58  determines if the message contains a cancel instruction. If it does, operation proceeds to step  86 . Otherwise, operation continues to step  88 . 
     In step  86 , control circuitry  58  causes display  54  to display primary display information  64  from primary portion  62  instead of temporary display information  68 . Operation returns to step  82  to wait for another message. 
     In step  88 , control circuitry  58  determines whether the message contains temporary display information  68  or primary display information  64 . If it contains primary display information  64 , operation proceeds to step  90 . Otherwise, operation continues to step  92 . 
     In step  90 , control circuitry  58  stores primary display information  64  from the message in primary portion  62  and causes display  54  to execute the instructions in the message, which include causing display  54  to display primary display information  64  in the message. Operation returns to step  82  to wait for another message. 
     In step  92 , control circuitry  58  determines whether temporary portion  66  has room to store temporary display information  68 . For example, if temporary portion  66  includes more than one group, control circuitry  58  looks for a vacant group. As another example, if temporary portion  66  includes a single data register  60 , control circuitry  58  determines whether it is vacant. If so, operation proceeds to step  96 . Otherwise, operation continues at step  94 . 
     In step  94 , control circuitry  58  clears temporary portion  66 . If temporary portion  66  includes more than one group, control circuitry  58  clears one of the groups. If temporary portion  66  includes a single data register  60 , control circuitry  58  determines clears that data register. 
     In step  96 , control circuitry  58  stores temporary display information  68  from the message in temporary portion  66  and causes display  54  to execute the instructions in the message, which include causing display  54  to display temporary display information  68  in the message. Operation returns to step  82  to wait for another message. 
     Since only a single message is needed to convey display information to EPL  22  instead of two messages, this method saves bandwidth and quickens display changes. 
     Turning now to FIG. 3B, a temporary display method corresponding to the second embodiment (FIG. 2B) is illustrated in more detail beginning with START  100 . 
     In step  102 , control circuitry  58  waits for a message from EPL computer  24  or a timer signal from a timer circuit (FIG.  3 B). If control circuitry  58  receives a message, operation proceeds to step  106 . If control circuitry  58  receives a timer signal, operation proceeds to step  104 . 
     In step  104 , control circuitry  58  causes display  54  to display primary display information  64  from primary portion  62  instead of temporary display information  68 . Operation returns to step  102  to wait for another message or timer signal. 
     In step  106 , control circuitry  58  determines whether the message contains temporary display information  68  or primary display information  64 . If it contains primary display information  64 , operation proceeds to step  108 . Otherwise, operation continues to step  110 . 
     In step  108 , control circuitry  58  stores primary display information  64  from the message in primary portion  62  and causes display  54  to execute the instructions in the message, which includes causing display  54  to display primary display information  64  in the message. Operation returns to step  102  to wait for another message. 
     In step  110 , control circuitry  58  determines whether temporary portion  66  has room to store temporary display information  68 . if so, operation proceeds to step  114 . Otherwise, operation continues at step  112 . 
     In step  112 , control circuitry  58  clears temporary portion  66 . 
     In step  114 , control circuitry  58  stores temporary display information  68  from the message in temporary portion  66  and causes display  54  to execute the instructions in the message, which includes causing display  54  to display temporary display information  68  in the message and initializing timer circuit  76  with time information contained in the instructions. Timing information is preferably included in the message containing temporary display information  68 , but may also be send in a separate message when time and/or bandwidth are not critical. Operation returns to step  102  to wait for another message. 
     Since only a single message is needed to convey display information to EPL  22  instead of two messages, this method saves bandwidth and quickens display changes. This method saves additional bandwidth and time because a cancel signal is not required. 
     Although the present invention has been described with particular reference to certain preferred embodiments thereof, variations and modifications of the present invention can be effected within the spirit and scope of the following claims. For example, EPL group management software  34  and EPL action software  38  may be a single application.