A dynamic pricing and information updating method for ink screen electronic price tags

Abstract

This application discloses a dynamic pricing and information updating method for e-ink electronic price tags, relating to the field of display control technology. The method includes: a server acquiring the content to be updated and the effective time of each electronic price tag; dividing the distribution clusters according to the access base station and link quality, and independently dividing them into presentation groups according to the field of view of each electronic price tag; allocating non-overlapping distribution time periods to each distribution cluster within a lead window before the effective time, and allocating different presentation times to each presentation group within a consistency tolerance window calculated from the effective time; distributing a preset message containing the content to be updated and the presentation time within the distribution time period; the electronic price tag writing the content to be updated to its local cache and maintaining the previous version of the displayed content; and each electronic price tag in the same presentation group simultaneously driving the e-ink display when its local timer reaches the presentation time. This application has the advantages of both peak-shifting transmission and price consistency within the same field of view.

Description

Technical Field

[0001] This application relates to the field of display control technology, and in particular to a dynamic pricing and information updating method for e-ink electronic price tags. Background Technology

[0002] Electronic shelf tags are used to display product prices and promotional information on shelves. The display units mostly use e-ink screens, which retain the existing image even when power is off, consuming power only when changing the image. Therefore, the tags can be powered by a single button battery and operate for several years. The content displayed on the tags is delivered by a server via a wireless network, with a single access base station managing hundreds to thousands of tags. Stores need to update the prices of batches of goods to the new values ​​at specified times, such as at the start of promotions or during time-slot pricing.

[0003] Maintaining consistency between shelf-labeled prices and checkout prices is a requirement for transparent pricing in stores. Discrepancies between the two can lead to customer complaints and penalties. Price tags are battery-powered and cannot be replenished individually; driving the e-ink screen to change the image is the most energy-consuming operation for price tags. The store's wireless channel is shared by all price tags, and time slots do not increase with the number of price tags. Therefore, price changes must be completed simultaneously at a specified time, provided that the channel capacity cannot be expanded and the power cannot be replenished.

[0004] Electronic price tags are typically updated using a drop-on-dropout approach. The server sends new display content to the price tag, and once received, the price tag immediately drives the e-ink screen to update the image. Therefore, the delivery of content and the display are synchronized. To avoid channel congestion during batch updates, the server splits the price tags to be updated into several batches and sends them out sequentially. The batch boundaries are determined by the last digit of the media access address, the location of the access base station, or the update capability of the price tag.

[0005] The delivery rhythm and presentation rhythm are tied together, making the requirements of simultaneously changing prices at a specified time and spreading out the distribution mutually exclusive: when distribution is concentrated around the specified time, the messages of each price tag compete for limited time slots in the same period, and the delivery delay increases with the queue length, with the price tag at the end of the queue receiving its content only after that time; when distribution is split into batches and carried out sequentially, the images of each price tag are spread out together with the order of distribution, and the price tags on the same shelf have both old and new prices existing simultaneously within a few minutes, and customers can see both prices at a single stop; however, the quantity based on the batch boundary is taken from the communication side and has no corresponding relationship with which price tags customers can see at the same time. Adjusting the batch division cannot remove the coexistence of old and new prices from the customer's field of vision. Adding base stations or increasing the transmission rate only shortens the queue length, without changing the binding between delivery and presentation. Summary of the Invention

[0006] In order to ensure that price changes for batch electronic shelf labels are spread out over time and remain consistent within the same customer's field of vision under the condition that the channel capacity cannot be expanded, this application provides a dynamic pricing and information updating method for e-ink electronic shelf labels.

[0007] This application provides a dynamic pricing and information updating method for e-ink electronic price tags, which adopts the following technical solution: A method for dynamic pricing and information updating of e-ink electronic price tags, comprising the following steps: S1. The server obtains the content to be updated for each electronic price tag and the effective time of the content to be updated; S2. The server divides each electronic shelf label into a distribution cluster according to the link quality between the access base station to which each electronic shelf label belongs and each electronic shelf label, and divides them into presentation groups independently according to the field of view unit where each electronic shelf label is located. The field of view unit is a shelf area that can be observed simultaneously at a single observation station. S3. The server allocates non-overlapping distribution time periods for each distribution cluster within the lead time window before the effective time, and allocates different presentation times for each presentation group within a preset consistency tolerance window calculated from the effective time. The presentation time of each presentation group is later than the distribution time period of the distribution cluster to which all electronic price tags in the presentation group belong. S4. The server sends a preset message to the electronic price tag in the distribution cluster during the distribution period. The preset message includes the content to be updated and the presentation time of the presentation group to which it belongs. S5. The electronic shelf label receives the preset message and writes the content to be updated to the local cache. The e-ink screen of the electronic shelf label continues to display the previous version of the content while the content to be updated resides in the local cache. S6. When their respective presentation conditions are met, each electronic price tag in the same presentation group simultaneously drives its own e-ink screen to display the content to be updated. The presentation conditions include the local time reaching the presentation time of the presentation group to which the tag belongs.

[0008] By adopting the above technical solution, the delivery stage carries message delivery with non-overlapping delivery time periods within the advance window, and the presentation stage carries screen switching with the presentation time of each presentation group within the consistency tolerance window. Both are arranged separately with the effective time as a common time axis anchor point, so that message unfolding and screen group switching no longer share the same time arrangement. The delivery cluster is taken from the access base station and link quality, and the presentation group is taken from the shelf area that can be observed simultaneously by a single observation station. The two sets of divisions are independent of each other, and the presentation time is later than the delivery time period of the delivery cluster to which the electronic price tag belongs in the group, so that the electronic price tags in the same customer's field of vision switch to the same version of display content at the same time.

[0009] Optionally, in step S5, after the content to be updated is written to the local cache, the electronic shelf label sends a receipt back to the server. The receipt includes the version number of the content to be updated received by the electronic shelf label, wherein each version of the content has a version number. Before step S6, the server determines the ready state of the presentation group based on the receipts of each electronic shelf label in the presentation group. The condition for the ready state to be ready is that all electronic shelf labels in the presentation group have sent back the receipt and the version number in each receipt is consistent. For presentation groups whose ready state is not ready, the server reallocates a presentation time later than the original presentation time and sends it to each electronic shelf label in the presentation group. The reallocated presentation time is within the preset consistency tolerance window and is different from the presentation time of each presentation group.

[0010] By adopting the above technical solution, the server determines the readiness status of the presentation group based on the received receipt before driving the e-ink screen. For the presentation group that is not ready, the presentation time is postponed to another time within the consistency tolerance window, so that the group switching is not broken up due to individual electronic price tags not receiving content.

[0011] Optionally, before step S6, if the server does not have an allocable presentation time later than the original presentation time within the preset consistency tolerance window, it compares the price value in the content to be updated with the price value in the previous version of the content, and determines the presentation mode of the presentation group at the end of the preset consistency tolerance window based on the comparison result. Specifically, if the content to be updated contains a price value and the price value in the content to be updated is lower than the price value in the previous version of the content, the presentation mode is that the electronic shelf labels within the presentation group that have already sent back the receipt drive their respective e-ink screens to present the content to be updated. If the content to be updated does not contain a price value or the price value in the content to be updated is not lower than the price value in the previous version of the content, the presentation mode is that each electronic shelf label within the presentation group maintains the presentation of the previous version of the content, and the server outputs the identifier of the viewing unit corresponding to the presentation group to the store terminal.

[0012] By adopting the above technical solution, when there is no available time to present within the consistency tolerance window, the flow is diverted according to the direction of price change: when the price is reduced, the ready electronic price tag is presented; otherwise, the previous version of the displayed content is maintained and the visual unit identifier is output, so that the failure falls on the side where the marked price is not higher than the settlement price.

[0013] Optionally, in step S6, after driving the e-ink screen, the electronic shelf label sends a presentation receipt back to the server. The presentation receipt contains the version number of the content currently displayed on the e-ink screen. The server uses the comparison result between the version number in each presentation receipt and the version number of the content to be updated as the criterion for determining whether the display status of each electronic shelf label is consistent with the content to be updated, and determines the display status of electronic shelf labels that have not sent back the presentation receipt as inconsistent with the content to be updated.

[0014] By adopting the above technical solution, the actual presentation version number carried by the presentation receipt is used as the basis for judging the display status, and electronic price tags that have not returned the presentation receipt are judged as inconsistent, so that the display status recorded by the server is taken from the actual screen of the e-ink screen rather than the delivery result of the message.

[0015] Optionally, in response to the electronic price tag recovering from a power outage that occurred after S5 before the effective time, the electronic price tag proactively reports a preset state declaration message to the server. The preset state declaration message includes whether the content to be updated to be displayed is stored in the local cache and the version number of the content to be updated to be displayed. When the preset state declaration message indicates that the content to be updated to be displayed is not stored in the local cache, or that the version number of the content to be updated to be displayed is inconsistent with the current version number of the content to be updated to be displayed, the server updates the ready state of the presentation group to which the electronic price tag belongs to to not ready, allocates a reissue time point for the electronic price tag that does not overlap with each of the issuance time points during the remaining time period of the lead window, and reissues the preset message to the electronic price tag at the reissue time point.

[0016] By adopting the above technical solution, the electronic price tag will proactively report the local cache status after power failure and recovery before the effective time. This allows the server to be aware of the cache being cleared before the lead time window ends, and to complete the re-issuance at a re-issuance time that does not overlap with the issuance period.

[0017] Optionally, in S4, the preset message further includes a validity credential, which includes the effective time and the version number of the content to be updated; in S6, the presentation condition further includes passing the pre-presentation verification. After the local timer reaches the presentation time, the electronic price tag performs the pre-presentation verification on the validity credential attached to the content to be updated residing in the local cache, and sends a non-presentation flag back to the server if the pre-presentation verification fails. The passing condition for the pre-presentation verification is that the version number in the validity credential is consistent with the version number in the most recent preset message received by the electronic price tag, and the local time of the electronic price tag is within the preset consistency tolerance window.

[0018] By adopting the above technical solution, the electronic price tag first verifies the validity of the certificate after the local time reaches the presentation time. If the version has been replaced or the local time exceeds the consistency tolerance window, the e-ink screen is not driven and the non-presentation mark is sent back, so that the invalid display content is not presented.

[0019] Optionally, in step S6, the electronic shelf label obtains the ambient temperature of the e-ink screen before driving it, and when the ambient temperature is lower than the preset waveform adaptation lower limit temperature, it splits the driving of the e-ink screen into multiple segmented driving sub-processes and executes them sequentially; when the multiple segmented driving sub-processes are not all completed, the electronic shelf label causes the e-ink screen to fall back to the previous version of the display content and sends a failure indicator back to the server.

[0020] By adopting the above technical solution, when the ambient temperature is lower than the lower limit temperature of waveform adaptation, the drive is divided into multiple segmented drive sub-processes. If not all of them are completed, the e-ink screen will fall back to the previous version of the displayed content, so that the drive at low temperature will not stay in the intermediate state of the incomplete image.

[0021] Optionally, in S3, the interval between the presentation times of the presentation groups corresponding to two adjacent visual fields is not greater than the travel time determined by a preset movement rate from the observation station of one visual field to the observation station of the adjacent visual field; after S3 and before S4, the server will adjust the electronic price tags that are located at the boundary of two adjacent visual fields and can be observed at the observation stations of the two adjacent visual fields to be assigned to the presentation group with the earlier presentation time in the presentation groups corresponding to the two adjacent visual fields.

[0022] By adopting the above technical solution, the time interval between the presentation of adjacent visual units is no greater than the travel time between two observation stations, and the electronic price tags observed on both sides at the boundary can be classified into the presentation group with the earlier presentation time, so that customers can see the same version of the price when moving along the shelf.

[0023] Optionally, in S1, the server further determines the estimated refresh time of the content to be updated based on the area of ​​the difference region between the content to be updated and the previous version of the electronic price tag recorded by the server, and the position of the difference region in the content to be updated; in S3, the server determines the lower limit of the interval between the presentation times of two adjacent presentation groups based on the maximum value of the estimated refresh times of each electronic price tag in the presentation group, and determines the duration of the distribution period allocated to the distribution cluster based on the sum of the data volume of the content to be updated of each electronic price tag in the distribution cluster.

[0024] By adopting the above technical solution, the lower limit of the presentation time interval between adjacent presentation groups is determined by the estimated refresh time converted from the area and position of the differential region, and the duration of the distribution period is determined by the sum of the data volume in the distribution cluster, so that the allocation of the two types of time resources is taken from the actual cost of their respective links.

[0025] Optionally, in S2, the basis for the server to divide the distribution clusters further includes the wake-up phase of each electronic shelf label, and the wake-up phases of each electronic shelf label within the same distribution cluster fall into the same wake-up window; in S4, the preset message further includes a wake-up phase offset, and the wake-up phase offset, the content to be updated, and the presentation time are carried in the same preset message, and are determined according to the distribution time period pre-scheduled by the server for the next update task; in S5, the electronic shelf label adjusts its wake-up phase according to the wake-up phase offset.

[0026] By adopting the above technical solution, the cluster division is based on the superimposed wake-up phase, so that each electronic price tag in the cluster falls in the same wake-up window. The wake-up phase offset is sent along with the preset message and determined according to the subsequent sending time period, so that the phase adjustment does not occupy additional messages and wake-up times.

[0027] Optionally, when the identifier of the shelf unit where the electronic price tag is located changes, the server rebuilds the presentation group, and the rebuilt presentation group takes effect from the next execution of S4.

[0028] By adopting the above technical solution, the division of display groups is updated after the shelf display is adjusted, and the update only takes effect when it is issued again, so that the ongoing update is not interrupted.

[0029] Optionally, when the number of viewing units is one, all electronic price tags are assigned to the same presentation group and their respective e-ink screens are driven simultaneously at the effective time.

[0030] By adopting the above technical solution, when the entire shelf area can be observed from a single observation station, the presentation time is no longer scattered, and all electronic price tags switch screens simultaneously at the time of activation.

[0031] Optionally, the server sets a preset cutoff point within the lead time window, and no new delivery time is allocated in the remaining time period after the preset cutoff point. The remaining time period is used to resend the preset message to electronic price tags that have not returned the receipt. The position of the preset cutoff point within the lead time window is determined based on the historical preset success rate of the delivery cluster.

[0032] By adopting the above technical solution, the tail period of the advance window is dedicated to re-sending, and the cutoff point is determined by the historical preset success rate of the sent cluster, so that the resend margin is commensurate with the failure situation of the cluster.

[0033] Optionally, the local cache of the electronic price tag retains only one copy of the content to be updated to be presented. The content to be updated in the preset message that arrives later completely overwrites the content to be updated that has been stored in the local cache, and the version number is updated synchronously.

[0034] By adopting the above technical solution, the local cache retains only one copy of the content to be presented, and multiple price changes before the effective time are based on the last one, so that the cache usage does not increase with the number of price changes.

[0035] Optionally, between S4 and S6, in response to a change in the content to be updated, the server sends a cancellation message to each electronic shelf label in the distribution cluster via a downstream broadcast frame. The cancellation message contains the changed version number, and each electronic shelf label cancels the content to be updated in its local cache according to the changed version number.

[0036] By adopting the above technical solution, when the displayed content changes after it has been issued, the already resident content is canceled by a downlink broadcast in one frame, and the time slot occupied by the cancellation does not increase with the number of electronic price tags.

[0037] Optionally, the local time of the electronic price tag is given by the local timer of the electronic price tag. The electronic price tag extracts the time base from the downlink broadcast frames periodically sent by the server and calibrates the local timer with the time base. The server does not send dedicated time authorization messages to the electronic price tag.

[0038] By adopting the above technical solution, the time base of the local timer is taken from the existing downlink broadcast frame, so that the timing reference of the presentation time can be aligned without adding a dedicated time message.

[0039] In summary, this application includes at least one of the following beneficial technical effects: 1. Using the effective time as a common time axis anchor point, the content delivery and screen presentation are arranged in time periods that do not occupy each other, so that while the message delivery is spread out within the advance window, the screen switching is still completed in groups within the consistency tolerance window.

[0040] 2. Determine the display status based on the actual version of the receipt. For cases where the receipt is not returned, verification fails, low-temperature drive is not completed, or the cache is cleared due to power failure, provide appropriate handling options such as maintaining the previous version of the display content or resending the receipt, so that the background records correspond to the shelf screen.

[0041] 3. The distribution clusters are divided according to the access base station and link quality, and the presentation groups are divided according to the shelf areas that can be observed simultaneously by a single observation station. The two divisions are independent of each other, so that the time difference caused by peak hours is constrained to the range that customers cannot see in one stop. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the overall process of dynamic pricing and information updating method for e-ink screen electronic price tags in one embodiment of this application.

[0043] Figure 2 This is a schematic diagram illustrating the independent division of the downlink cluster and the presentation group in one embodiment of this application.

[0044] Figure 3 This is a schematic diagram illustrating the arrangement of time periods and times within the lead window and consistency tolerance window in one embodiment of this application.

[0045] Figure 4 This is a schematic diagram illustrating the process of determining the group's ready state and handling the end point of the consistency tolerance window in one embodiment of this application. Detailed Implementation

[0046] The present application will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the application and are not intended to limit the scope of the application.

[0047] This application discloses a dynamic pricing and information updating method for e-ink electronic shelf labels. This application uses the price's effective time as a common time axis anchor point, separating the delivery of display content to the electronic shelf label and the change of the electronic shelf label's screen into two independent time periods. Furthermore, it employs two sets of divisions based on different physical quantities for the delivery and presentation stages. First, the server obtains the content to be updated and the effective time for each electronic shelf label. Based on the access base station and link quality, the electronic shelf labels are divided into distribution clusters, and based on the shelf area that a customer can simultaneously see from a single location, they are divided into presentation groups. Then, within a lead time window before the effective time, non-overlapping distribution time periods are arranged for each distribution cluster. Within a consistency tolerance window calculated from the effective time, different presentation times are arranged for each presentation group. Finally, the electronic shelf label stores the received display content locally and maintains the original screen until the local timer reaches the presentation time of its group, at which point the e-ink screen is activated. Therefore, message delivery can be spread out within the advance window without coinciding with the effective time. Electronic price tags that meet all presentation conditions can switch to the same version of display content at the same time, so that the same price is displayed in the same customer's field of vision. Electronic price tags that do not meet the presentation conditions can either maintain the previous version of display content or fall back, which will be discussed in the corresponding steps below.

[0048] The following provides a detailed explanation of the terminology, application environment and overall process, specific implementation of each step, readiness determination of the presentation group and handling of the consistency tolerance window endpoint, and module mapping. First, we will explain several technical terms involved in the embodiments of this application.

[0049] E-ink displays are bistable display devices that operate on the principle of electrophoretic display. The display medium of an e-ink display consists of charged microparticles and a suspension. Under the influence of a driving electric field, the microparticles migrate to or away from the viewing surface, creating contrast. After the electric field is removed, the microparticles remain in place due to the viscosity of the suspension, allowing the image to be maintained for a long time even when power is off. Therefore, e-ink displays only consume power when changing the image; power consumption during static display is close to zero. The process of changing the image is accomplished by a pre-tuned driving waveform. The duration and voltage sequence of this waveform are tuned according to the migration characteristics of the display medium at room temperature. As the viscosity of the display medium increases with decreasing temperature, the amount of microparticle migration driven by the same waveform decreases accordingly.

[0050] The displayed content refers to the data corresponding to a complete image displayed on the e-ink screen of the electronic shelf label. It includes elements such as product name, price, unit of measurement, and promotional logos. The price is an optional element; versions that only change the promotional logos do not include the price. The currently displayed content on the electronic shelf label is called the previous version, and the version that the server requires it to be updated to at a specified time is called the content to be updated. Each version of the displayed content has a version number, which the server assigns to each version in a monotonically increasing sequence based on the order of generation. In this method, the version number can have four possible values: the target version required by the server, the version in the most recent preset message registered by the electronic shelf label, the cached version residing in the local cache of the electronic shelf label, and the version currently displayed on the e-ink screen. These are distinguished by source qualifiers during comparison.

[0051] The effective time is the moment the server requires the content to be updated to begin appearing on the shelf. This is determined by the pricing plan, such as the hourly start of a promotion or the point where pricing tiers switch during a time period. The consistency tolerance window is a duration starting from the effective time. If the server completes the screen switching of all electronic price tags within this duration, it is considered to meet the consistency requirement between the shelf price and the checkout price. The checkout will settle the transaction based on the price value in the content to be updated, starting from the effective time. The length of the consistency tolerance window is preset by the server according to the store's compliance standards, for example, set to 60 seconds. This window is a closed interval including the endpoint; the moment falling on the endpoint is still within the window.

[0052] An access base station is a wireless relay device between the server and the electronic shelf labels. One access base station covers an area within a store, supporting hundreds to thousands of electronic shelf labels. Link quality is a rating given by the server based on the signal-to-noise ratio and retransmission count carried in each uplink frame of the electronic shelf label. It characterizes the reliability of the wireless link between the electronic shelf label and its access base station.

[0053] A delivery cluster is a division of electronic shelf labels by the server to arrange the order of message delivery. Electronic shelf labels within the same delivery cluster receive messages at the same time.

[0054] The lead time window is a period of time before the effective time to complete message delivery, such as 30 minutes before the effective time.

[0055] The delivery time period is a period of time allocated to a certain delivery cluster within the advance window. The delivery time periods of each delivery cluster do not overlap, so that the messages of different delivery clusters are staggered on the timeline.

[0056] Unlike the classification criteria derived from wireless link conditions mentioned above, this method introduces another set of terms derived from the customer's observation position. An observation position is the location where a customer stands and selects items within a store aisle. A viewing unit is a shelf area that can be simultaneously observed from a single observation position; its boundary is defined by the orientation of the shelf rows and the direction of the aisle. Standing in an aisle between two rows of shelves, a customer can simultaneously see the shelf sections directly opposite each other on both sides of the aisle. Adjacent sections obscured by shelf back panels and sections after turning a corner do not fall into the same viewing unit. A shelf unit is the installation location of an electronic price tag on a shelf and is labeled. A shelf section is a spatial area on the shelf facade, containing several shelf units.

[0057] A presentation group is a division of electronic shelf labels by the server based on field of view. Electronic shelf labels within the same field of view are grouped into the same presentation group. A presentation time is the screen switching time specified by the server for a particular presentation group. Electronic shelf labels within the same presentation group that meet all presentation conditions simultaneously activate their respective e-ink displays at that time. The division of presentation groups is based on the customer's observation position, while the division of distribution clusters is based on the physical conditions of the wireless link. These two sets of divisions are independent of each other based on different physical quantities. The same electronic shelf label simultaneously belongs to one distribution cluster and one presentation group.

[0058] A preset message is a message sent by the server to the electronic shelf label during the specified time period. Its payload includes the content to be updated and the presentation time of the presentation group to which the electronic shelf label belongs.

[0059] The local cache is a storage area within the electronic shelf label used to store the content to be displayed. The act of writing the display content to the local cache does not drive the e-ink screen, and the e-ink screen continues to display the previous version of the content during this period.

[0060] Presentation conditions are the set of conditions that the electronic price tag must meet to drive the e-ink screen, and the local timer reaching the presentation time of this group is one of them.

[0061] A receipt is an uplink frame sent back to the server after the electronic shelf label has written the content to be updated to its local cache, indicating that the message has been received and added to the cache. A presentation receipt is an uplink frame sent back by the electronic shelf label after it has activated the e-ink display, carrying the version number of the content currently displayed on the e-ink display. These two types of receipts correspond to the message delivery and screen switching stages, respectively, allowing the server to track the completion status of each stage.

[0062] When an electronic shelf label fails to complete a screen transition, there are two additional types of uplink frames: a "Not Presented" flag, sent back when pre-presentation verification fails and the e-ink screen is not driven; and a "Presentation Failed" flag, sent back after the e-ink screen has been driven but the screen transition has not been completed and the screen has reverted to the previous display content. The server treats these two types of uplink frames the same as if no uplink frames were received, and does not use them to determine that the electronic shelf label has presented the content to be updated.

[0063] The terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects, not to describe a specific order or sequence. Terms such as "comprising" and "having" are intended to cover non-exclusive inclusion; when a series of steps or elements includes the listed steps or elements, other steps or elements not listed are not excluded.

[0064] The application environment of this method is described below. This method is applied to a star network consisting of a server, an access base station, and electronic shelf labels. The server interfaces with the store's pricing system, obtains the price adjustment plan, and schedules update tasks. The scheduling results are sent downlink via the access base station's wireless link to the electronic shelf labels within its coverage area. The uplink frames of the electronic shelf labels are sent back to the server along the same link. Electronic shelf labels do not communicate directly with each other; all messages are forwarded through the server and the access base station.

[0065] The electronic shelf labels are powered by button batteries and periodically wake up according to a pre-configured wake-up phase. During the wake-up period, they receive downlink frames and calibrate the timing. At other times, they are in a low-power state. The wireless transceiver and display driver of the electronic shelf labels do not operate in the low-power state. In addition to the periodic wake-up, the local timer of the electronic shelf labels generates an interrupt to wake up the main controller at a pre-written time. Taking the fresh food section of the store as an example, this section is covered by an access base station. Shelves are arranged in rows R1, R2, and R3. The rows of shelves are connected by aisles for customers. The positions where customers stop to select items in the aisles are marked as observation positions P1, P2, and P3. A total of 600 electronic shelf labels are installed on each shelf row.

[0066] This method is for updating the content of electronic shelf labels that are already displaying the previous version on the shelf. For electronic shelf labels that have been newly deployed, replaced, or restored to factory settings and have not yet displayed any content, the server sends the first version of the display content through an instant delivery channel and directly drives the display. This process does not involve maintaining the previous version of the display content, nor does it require switching screens with other electronic shelf labels at the same time, and is not within the scope of this method.

[0067] The overall process of this method is described in detail below. (Refer to...) Figure 1This method includes steps S1 to S6, which are, in order, obtaining the content to be updated and the effective time, dividing the distribution cluster and the presentation group, arranging the distribution time period and the presentation time, distributing the preset message, residing the display content in the local cache, and driving the e-ink screen after the presentation conditions are met. The following steps are carried out in this order.

[0068] The following explains step S1.

[0069] S1. The server obtains the content to be updated and the effective time of the content to be updated for each electronic price tag.

[0070] The content to be updated is provided by the store's pricing system. After the pricing system completes the scheduling of promotional activities, adjustments to time-based pricing tiers, or temporary price changes, it submits the relevant product codes, new price values, and layout templates to the server. The server then renders the content to be updated for each electronic shelf tag and assigns it a version number according to the order of generation. The effective time is provided with each submission, and all electronic shelf tags involved in the same submission share the same effective time. The server categorizes the electronic shelf tags involved in this submission into the same update task. For example, if a promotional submission in the fresh produce section involves 600 electronic shelf tags, with an effective time of 9:00 AM on the same day, the server assigns version number v2 to the display content in this update task, and the version number of the currently displayed content on each electronic shelf tag is v1.

[0071] In some embodiments, S1 further includes determining the estimated refresh time. The server determines the estimated refresh time of the content to be updated based on the area of ​​the difference region between the content to be updated and the previous version of the electronic price tag recorded by the server, and the position of the difference region within the content to be updated. The server stores the currently displayed content of each electronic price tag. By comparing the content to be updated with it pixel by pixel, the difference region can be obtained. The area of ​​the difference region reflects the number of display media that need to be migrated, and the position of the difference region reflects the functional area to which that area belongs on the display. Both together determine the time required for the e-ink screen to change the image. The estimated refresh time is determined by the following formula: in, To estimate refresh time, This is the baseline full-screen refresh time for this model of e-ink display. This represents a percentage of fixed costs that are independent of the differential area. This represents the percentage of the differential region's area in the total page area. This refers to the weighting coefficient corresponding to the location of the difference region; a larger value is taken for the main display area in the center of the page, and a smaller value is taken for the corners of the page. For example, a certain model of e-ink screen... Second, The difference area of ​​a certain electronic price tag falls in the price value area in the middle of the page. , ,but Seconds; the difference in area of ​​another electronic price tag falls in the promotional label area at the corner of the page. Both are 0.12. ,but Seconds. The estimated refresh time is then used as input for the S3 layout presentation time.

[0072] The estimated refresh time can also be obtained by the server looking up a table according to the refresh mode. The server pre-stores a time table for each model of e-ink screen. The table records the measured time values ​​for both global refresh and partial refresh modes. The server selects the refresh mode based on whether the difference area spans multiple functional areas, and then reads the corresponding time from the table. This method does not require pixel-by-pixel comparison of the layout and can still obtain the estimated refresh time usable by S3.

[0073] Step S2 will be explained below.

[0074] S2. The server divides each electronic shelf label into a distribution cluster based on the link quality between the access base station to which each electronic shelf label belongs and each electronic shelf label. The server then independently divides each electronic shelf label into a presentation group based on the field of view unit where each electronic shelf label is located. The field of view unit is the shelf area that can be observed simultaneously from a single observation station.

[0075] S2 includes sub-steps S21 to S22.

[0076] S21. The server divides the distribution clusters according to the access base station and link quality of each electronic price tag. The server reads the access base station affiliation of each electronic price tag from the electronic price tag ledger, and then reads the average signal-to-noise ratio and retransmission count from the statistics of each uplink frame. It assigns the link quality level according to the preset grading rules, and electronic price tags of the same level under the same access base station are assigned to the same distribution cluster. The division result is a distribution cluster list, which records the number of electronic price tags and the link quality level contained in each distribution cluster, for use in S3 when allocating distribution time periods. Electronic price tags of weak link levels are grouped into separate clusters so that they can obtain a time period length commensurate with the retransmission requirements in S3. For example, 600 electronic price tags in the fresh produce area are covered by one access base station and are divided into distribution cluster C1 (near-end strong link) and distribution cluster C2 (far-end weak link) according to link quality, containing 420 and 180 electronic price tags respectively.

[0077] In some embodiments, in S2, the server's division of distribution clusters also includes the wake-up phase of each electronic price tag. The wake-up phases of each electronic price tag within the same distribution cluster fall into the same wake-up window. The wake-up phase is the starting point for the electronic price tag to wake up, and the wake-up window is the time range within which a set of wake-up starting points fall. Electronic price tags can only receive downlink frames during their respective wake-up phases. If the distribution period falls within the dormant period of some electronic price tags within the cluster, those electronic price tags will not receive messages. After the wake-up phase is incorporated into the clustering criteria, electronic price tags within the same distribution cluster wake up together within the same wake-up window. Aligning the distribution period allocated to that cluster with the wake-up window will cover all electronic price tags within the cluster.

[0078] The division of distribution clusters can also be based on physical location. Electronic shelf tags within the same shelf row, shelf layer, or product category area are close to the access base station in terms of distance and obstruction conditions, and their link conditions are naturally similar. Clustering them according to physical boundaries also yields a list of distribution clusters available for S3. The distribution order of each electronic shelf tag within a cluster is constructed by the signal-to-noise ratio carried by each received acknowledgment and the remaining power, with those having lower signal-to-noise ratios placed first to occupy idle time slots.

[0079] S22. The server divides presentation groups based on the viewing area of ​​each electronic shelf tag. The server reads the direction, aisle location, and orientation of each shelf row from the store floor plan and shelf layout ledger, defining viewing areas accordingly. Then, it determines the viewing area to which each electronic shelf tag belongs based on the shelf section where it is installed. Electronic shelf tags within the same viewing area are grouped into the same presentation group. The result is a list of presentation groups, recording the viewing area identifier and the number of electronic shelf tags in each group, used by S3 to allocate presentation times. Each electronic shelf tag belongs to only one presentation group, ensuring its screen transition time is uniquely determined.

[0080] The definition of a viewing unit is based on the customer's observation range within the aisle. When a customer stands in the aisle between two rows of shelves, they can simultaneously see the shelf sections directly opposite each other on both sides of the aisle; this group of sections constitutes a viewing unit. The back sections obscured by the shelf back panels belong to the observation range of the adjacent aisle. Sections beyond the corner of the aisle are beyond the current viewing direction and do not fall within the viewing unit. Taking the fresh produce section as an example, observation position P1 is taken in the aisle between shelf rows R1 and R2. The shelf sections facing the aisle from R1 and R2 constitute viewing unit V1, and the electronic price tags on them are assigned to presentation group G1, totaling 240 tags. Observation position P2 in the aisle between R2 and R3 corresponds to viewing unit V2 and presentation group G2, totaling 230 tags. Observation position P3 on the side of R3 closest to the outer wall corresponds to viewing unit V3 and presentation group G3, totaling 130 tags.

[0081] In addition to defining the visual field according to the direction of the shelving and the direction of the aisles, the visual field unit can also be taken from the visual cone coverage on the floor plan. The server sets up observation positions on the floor plan according to the direction of the aisles. With each position as the vertex and the visible angle of the human eye in front of the shelving as the visual cone, the segment intercepted by the intersection of the visual cone and the shelving facade is the visual field unit corresponding to that position. Based on this, non-overlapping visual field units and presentation groups are obtained.

[0082] Reference Figure 2 The distribution clusters and presentation groups are divided based on different physical quantities. They are independent of each other and not nested. Electronic price tags within the same distribution cluster can belong to different presentation groups, and electronic price tags within the same presentation group can also belong to different distribution clusters. Taking the fresh produce section as an example, electronic price tag T1 on shelf row R1, which is closer to the access base station, belongs to distribution cluster C1 and presentation group G1. Electronic price tag T2 on R1, which is farther from the access base station, belongs to distribution cluster C2 and presentation group G1. Electronic price tag T3 on shelf row R2, which is closer to the access base station, belongs to distribution cluster C1 and presentation group G2. The messages of T1 and T2 are delivered at different distribution times, but their images switch at the same presentation time; the messages of T1 and T3 are delivered at the same distribution time, but their images switch at different presentation times.

[0083] The shelves, aisles, and observation stations in the diagram constitute the store's floor plan. The field of view units are drawn along the opposite sections on both sides of the aisle, while the downlink clusters are drawn according to the link conditions between each electronic price tag and the access base station. The two sets of boundaries intersect each other on the same plane. In the case of multiple field of view units, the range of any downlink cluster does not fall within the range of a certain presentation group.

[0084] To accommodate display adjustments, in some embodiments, when the labeling of the shelf unit where the electronic shelf tag is located changes, the server rebuilds the presentation group. The rebuilt presentation group takes effect from the next execution of S4. When the electronic shelf tag moves to another shelf section with the merchandise, its viewing area changes accordingly, and the original grouping no longer corresponds to the customer's observation range. The server re-executes S22 when the shelf unit labeling changes. The reconstruction result does not apply to the currently executing update task, but is enabled from the next time a preset message is sent, ensuring that the grouping remains unchanged during the execution of an update task.

[0085] In other embodiments, when the number of viewing units is one, all electronic price tags are grouped into the same presentation group and their respective e-ink screens are activated simultaneously at the time of activation. Small stores or merchandise areas displayed on a single wall can be seen entirely from one observation position. In this case, there are no adjacent viewing units that need to be staggered, and the presentation time is no longer dispersed. This situation also belongs to the implementation method of dividing presentation groups according to viewing units.

[0086] Based on the above-mentioned cluster list and presentation group list, step S3 is explained below.

[0087] S3. The server allocates non-overlapping distribution time periods to each distribution cluster within the lead window before the effective time, and allocates different presentation times to each presentation group within the preset consistency tolerance window calculated from the effective time. The presentation time of each presentation group is later than the distribution time period of all distribution clusters to which all electronic price tags in the presentation group belong.

[0088] S3 includes sub-steps S31 to S33.

[0089] S31. The server allocates non-overlapping delivery time slots to each delivery cluster within the lead time window. (Refer to...) Figure 3 The server retrieves a lead time window starting from the effective time and divides the timeline within the window into segments based on the cluster number in the batching list. Each cluster is allocated a time period, ensuring that the segments are contiguous and do not overlap, resulting in a batching timetable. This table then serves as the basis for S4 to send pre-set messages. The batching time periods do not overlap, preventing messages from different batches from competing for time slots in the same period. Continuing with the previous scenario, if the effective time is 9:00 AM, the lead time window is 30 minutes prior to the effective time, i.e., from 8:30 AM to 9:00 AM.

[0090] The upper and lower time axes in the figure correspond to the distribution side and the presentation side, respectively. The two axes are aligned with the effective time. The lead time window is located on the side before the effective time, and the consistency tolerance window is located on the side after it. Each distribution period and each presentation time fall on the two sides and do not share the same time period.

[0091] In some embodiments, in S3, the server determines the duration of the distribution period allocated to the distribution cluster based on the sum of the data volume of the electronic price tags to be updated within each distribution cluster. The server first calculates the base duration of the cluster based on the sum of the data volume of each piece of content to be updated within the cluster, and then adds a retransmission margin to the base duration according to the link quality level of the cluster. For example, if the data volume of each piece of content to be updated is 12 kilobytes, the total data volume of distribution cluster C1 is 5040 kilobytes, the base duration is 14 minutes, its link quality is strong, and no margin is added, the distribution period is from 8:30 to 8:44; the total data volume of distribution cluster C2 is 2160 kilobytes, the base duration is 6 minutes, its link quality is weak, and half of the base duration is added as a retransmission margin, the duration is 9 minutes, the distribution period is from 8:44 to 8:53. The remaining 7 minutes within the lead window are not allocated to any subsequent clusters and are reserved for resending.

[0092] The distribution time slots can also be arranged according to the length of the lead time. The server classifies update tasks with a lead time of tens of minutes or more into the planned slot and temporary price changes with a lead time of a few minutes or less into the short slot. The distribution time slots in the planned slot are arranged sequentially from the start of the lead time window, and the short slots are inserted into unused idle time slots. When there are electronic price tags in a cluster with remaining power below a preset threshold, the server moves the distribution time slot of that cluster forward, so that it can be received before the power further decreases. The above arrangement also results in a non-overlapping distribution time slot table.

[0093] S32. The server assigns distinct presentation times to each presentation group within a consistency tolerance window. Starting from the effective time, the server retrieves the consistency tolerance window, assigns a time to each presentation group within the window, and ensures that the times of each group are pairwise distinct, resulting in a presentation time table. The times in the table are then written into a preset message by S4 and compared locally by the electronic price tag. The distinct presentation times of each presentation group ensure that the screen switching of adjacent view units is staggered in time, preventing the superposition of current and channel spikes at the same moment.

[0094] In some embodiments, in S3, the server determines the lower limit of the interval between the presentation times of two adjacent presentation groups based on the maximum estimated refresh time of each electronic shelf label within the presentation group. The next group begins driving before the e-ink screen of the previous group has completed its screen switching, and the driving currents of the two groups are superimposed over time. Therefore, the presentation times of two adjacent groups are at least separated by the time required for the longest-lasting electronic shelf label in the previous group to complete one refresh. Continuing with the aforementioned scenario, the electronic shelf label with the largest differential area in presentation group G1 has a differential area ratio of 0.2, a position weight coefficient of 1.0, and an estimated refresh time of 0.6 seconds. Based on this, the lower limit of the presentation time interval between G1 and G2 is determined to be 0.6 seconds, and the presentation times of each presentation group within the consistency tolerance window are not less than this lower limit.

[0095] In other embodiments, in S3, the interval between the presentation times of the presentation groups corresponding to two adjacent view units is no greater than the travel time from the observation station of one view unit to the observation station of the adjacent view unit, determined by a preset movement rate. If the presentation time interval between two adjacent presentation groups exceeds the time taken for a customer to walk from one observation station to the adjacent station, and the group has not yet switched screens when the customer walks to the next station, the customer will see the price that has not yet been updated in the adjacent view unit. Continuing with the aforementioned scenario, the observation stations P1 and P2 are 6 meters apart, the preset movement rate is 1.0 meter per second, and the travel time is 6 seconds; the interval between presentation times therefore falls between 0.6 seconds and 6 seconds, with the server taking 2 seconds. The presentation time of presentation group G1 is 9:00 AM, G2 is 2 seconds after 9:00 AM, and G3 is 4 seconds after 9:00 AM, all three falling within the consistency tolerance window.

[0096] When the passage duration is less than the lower limit of the interval, both constraints cannot be satisfied simultaneously. At this time, the server prioritizes the passage duration, merging the two presentation groups corresponding to the pair of adjacent view units into one presentation group and sharing the same presentation time, so that there is no longer any difference in the picture between the two view units; when the number of electronic price tags driven simultaneously after merging exceeds the power supply and channel capacity of the access base station, the presentation time of the latter group is postponed to the nearest available time point that meets the lower limit of the interval.

[0097] In some embodiments, between S3 and S4, the server adjusts electronic price tags located at the boundary of two adjacent viewing units, and which can be observed from the observation positions of both adjacent viewing units, to the presentation group with the earlier presentation time in the respective presentation groups of the two adjacent viewing units. Electronic price tags at the end of a shelf are visible in both aisles, and their display will have a time difference with the other group regardless of which group is switched. Assigning them to the group with the earlier presentation time allows the electronic price tag to display the new price first. Continuing with the aforementioned scenario, the electronic price tag at the end of shelf R2, originally belonging to presentation group G2 and presented 2 seconds after 9:00, is adjusted to presentation group G1, with a presentation time of 9:00, because it can be observed from both observation positions P1 and P2. This grouping adjustment is only used to illustrate the rules for assigning electronic price tags at the boundary; subsequent scenarios will follow the grouping before the adjustment.

[0098] S33. The server verifies that the presentation time of each presentation group is later than the distribution time of all distribution clusters to which the electronic price tags within the presentation group belong. Distribution clusters and presentation groups are divided according to different physical quantities. Members of a presentation group may be scattered across multiple distribution clusters. Therefore, during verification, the latest distribution time among the distribution clusters to which the group members belong is used as the comparison benchmark. Continuing with the previous scenario, the members of presentation group G1 belong to distribution clusters C1 and C2, and their distribution times end at 8:44 and 8:53 respectively. Taking 8:53 as the benchmark, G1's presentation time of 9:00 is later than this benchmark, and the verification passes. If the verification fails, the server moves the distribution time of the corresponding distribution cluster forward, or postpones the presentation time of the presentation group to the next available time point within the consistency tolerance window, until all presentation groups pass the verification.

[0099] Step S4 will be explained below.

[0100] S4. During the distribution period, the server sends a preset message to the electronic price tags in the distribution cluster. The preset message contains the content to be updated and the presentation time of the display group to which it belongs.

[0101] The server initiates distribution cluster by cluster according to the distribution time schedule. Within the distribution time of a certain distribution cluster, preset messages are sent to each electronic price tag in that cluster in order. The payload of the preset message contains two essential pieces of information: the content to be updated for the electronic price tag and the presentation time of the presentation group to which the electronic price tag belongs. The former is used by the electronic price tag to write to its local cache, and the latter is used by the electronic price tag for local timing comparison. The header of the preset message also carries the version number of the content to be updated. This header is used for integrity verification independently of the payload. Even if the integrity verification of the payload fails, the electronic price tag still registers the version number carried in the header as the version number of the most recent preset message. Continuing with the above scenario, the 420 electronic price tags in distribution cluster C1 received their respective preset messages between 8:30 and 8:44. The electronic price tags belonging to presentation group G1 received their presentation time at 9:00, and the electronic price tags belonging to presentation group G2 received their presentation time 2 seconds after 9:00.

[0102] In some embodiments, in S4, the preset message also includes a validity credential, which includes the effective time and the version number of the content to be updated. The credential resides in the local cache along with the displayed content. Before driving the e-ink screen, the electronic shelf label uses this credential to verify whether the content in the local cache is still the version required by the server. The verification method is described in S6. The credential and the displayed content are delivered with the same message; the electronic shelf label does not need to query the server separately before displaying.

[0103] In other embodiments, in S4, the preset message also includes a wake-up phase offset. The wake-up phase offset, the content to be updated, and the presentation time are carried in the same preset message and are determined based on the subsequent distribution time slot to be allocated by the server. While scheduling the current distribution time slot, the server pre-schedules the distribution time slot for the next update task, writing the difference between the wake-up phase of each electronic shelf label and its corresponding distribution cluster in the next distribution time slot as an offset into the current preset message. The offset is delivered with the existing message; the server does not send a separate configuration message for phase adjustment, and the electronic shelf label does not wake up additionally to receive this configuration.

[0104] To handle situations where prices change again after initial distribution, in some embodiments, between S4 and S6, in response to a change in the content to be updated, the server sends a cancellation message to each electronic shelf label within the distribution cluster via a downstream broadcast frame. The cancellation message contains the changed version number, and each electronic shelf label invalidates the content to be updated in its local cache based on the changed version number. The cancellation message is broadcast in one frame, covering the entire cluster, and its time slot does not increase with the number of electronic shelf labels in the cluster. The electronic shelf label compares the version number in the cancellation message with the version number of the content residing in its local cache. If they do not match, the cached content is invalidated, and the previous version of the display content continues to be displayed, waiting for the server to re-distribute within the remaining lead window.

[0105] Step S5 will be explained below.

[0106] S5. The electronic shelf label receives a preset message and writes the content to be updated to the local cache. While the content to be updated resides in the local cache, the e-ink screen of the electronic shelf label continues to display the previous version of the content.

[0107] The electronic shelf label listens for downlink frames within its wake-up window according to its own wake-up phase. After receiving a preset message sent to the local unit, it first verifies the integrity of the frame, then writes the content to be updated in the payload to the local cache, and writes the presentation time in the payload to the comparison register of the local timer. The writing operation only involves the memory and timer, and does not touch the driving circuit of the e-ink screen. Therefore, the charged particles in the display medium maintain their original distribution, and the e-ink screen continues to display the previous version of the display content. After the writing is completed, the electronic shelf label returns to a low-power state. The content to be updated in the local cache is in a waiting-to-present state during this period until the presentation condition of S6 is met. Continuing with the above scenario, the electronic shelf label T1 receives a preset message at 8:35, writes the display content with version number v2 to the local cache and records the presentation time given in the message. Its e-ink screen continues to display the previous version of the display content with version number v1 from 8:35 until the presentation time arrives.

[0108] In some embodiments, the local cache of the electronic shelf label retains only one copy of the content to be updated. Subsequent pre-set messages completely overwrite the existing content in the local cache, and the version number is updated synchronously. If the product price is adjusted again before the effective time, the server will send a second pre-set message for the same electronic shelf label. The local cache does not establish a queue for this; instead, the later message completely replaces the earlier one. Therefore, cache usage does not increase with the number of price changes, and the result of the last price change is retained in the cache when the display time arrives.

[0109] Local caching can also adopt a dual-buffer structure with the current frame and preset frame separated. The current frame stores the previous version of the display content that the e-ink screen is currently displaying, while the preset frame stores the content to be updated and displayed. Each occupies a separate storage area without overwriting the other. When driving the e-ink screen, data is retrieved from the preset frame. If the screen transition fails to complete, the previous version of the display content is retrieved from the current frame and the screen is driven again. This structure also ensures that the display content to be updated does not affect the e-ink screen's display during its dwell time and provides an additional baseline image for fallback.

[0110] In other embodiments, in step S5, the electronic shelf label adjusts its wake-up phase based on a wake-up phase offset. The electronic shelf label retrieves the offset from a preset message and shifts the starting point of the next wake-up by that offset before the current wake-up ends. Thereafter, it periodically wakes up according to the adjusted wake-up phase. The phase adjustment and the writing of the display content are completed within the same wake-up cycle; the electronic shelf label does not require an additional wake-up for this purpose.

[0111] To handle power outages within the lead time window, in some embodiments, in response to the electronic price tag recovering from a power outage that occurred after S5 before the effective time, the electronic price tag proactively reports a pre-set state declaration message to the server. The pre-set state declaration message includes whether the content to be updated to be displayed is stored in the local cache and the version number of the content to be updated to be displayed.

[0112] When the server indicates in the pre-set declaration message that the content to be updated to be displayed is not resident in the local cache, or that the version number of the resident content to be updated to be displayed is inconsistent with the current version number of the content to be updated to be displayed, the server updates the ready status of the presentation group to which the electronic price tag belongs to to not ready. During the remaining time period of the lead window, the server allocates a reissue time point for the electronic price tag that does not overlap with each issuance time period, and reissues the pre-set message to the electronic price tag at the reissue time point.

[0113] When a store experiences a battery replacement or a momentary power outage due to a drop of an electronic shelf label during business hours, the content in the local cache is cleared. Since the electronic shelf label does not generate uplink frames during the power outage, the server is unaware of this. Upon power restoration, the electronic shelf label proactively reports the missing information, ensuring that the missing information is detected before the lead time window expires, allowing the server to resend the missing information. Continuing with the aforementioned scenario, electronic shelf label T2 completes its preset state at 8:48 AM, experiences a power outage due to battery replacement at 8:50 AM, and is restored to power at 8:52 AM, reporting a preset state declaration message indicating that no content awaiting presentation resides in the local cache. Based on this, the server updates the ready state of presentation group G1, to which T2 belongs, to not ready. Within the remaining lead time window between 8:53 AM and 9:00 AM, 8:56 AM is chosen as the resend time. This time does not overlap with the delivery time of delivery clusters C1 and C2. The server resends the preset message to T2 at this time.

[0114] The following section explains the determination of the readiness status of the presentation group and the redistribution of presentation time.

[0115] In some embodiments, in S5, after the electronic price tag writes the content to be updated to the local cache, it sends a receipt back to the server. The receipt contains the version number of the content to be updated received by the electronic price tag, wherein each version of the content has a version number.

[0116] Prior to S6, the server determined the readiness status of the presentation group based on the receipts from each electronic shelf label within the group. The condition for the readiness status to be "ready" was that all electronic shelf labels within the presentation group had sent back receipts and that the version number in each receipt was consistent.

[0117] For presentation groups that are in a ready state but not ready, the server reallocates a presentation time later than the original presentation time and sends it to each electronic price tag in the presentation group. The reallocated presentation time is within the consistency tolerance window and is different from the presentation times of each presentation group.

[0118] Reference Figure 4 The receiving receipt sends the completion status of message delivery back to the server. The server maintains a receipt ledger for each presentation group, recording whether each electronic price tag in the group has received a receipt and the version number carried in the receipt. Based on this, the server determines whether the entire group can switch screens before the presentation time arrives. If all receipts for the group are complete and the version numbers are consistent, it indicates that the same version of display content resides in the local cache of each electronic price tag in the group, and the content displayed on each screen will be the same after the drive is initiated. If a receipt is missing or the version numbers are incomplete, once the group is driven at the original presentation time, both the old and new versions of the price will appear simultaneously in the same field of view. For electronic price tags that have received a receiving receipt but are subsequently indicated by a preset declaration message that the local cache does not contain the content to be presented, the receiving receipt will no longer be considered as evidence that the presentation group is ready.

[0119] The redistribution of the presentation time postpones the switchover of the entire group until the gap is filled. The redistributed time is later than the original presentation time, allowing the server time to resend the data between the two; this time still falls within the consistency tolerance window, ensuring that the delay does not exceed the compliance limit; this time is different from the presentation times of the other presentation groups, ensuring that the delayed group does not collide with the groups of adjacent view units at the same time. Following the aforementioned scenario, group G1 contains 240 electronic price tags. By the preset deadline of 8:53, all receipts for this group were complete and the version serial numbers were consistent. At 8:52, the server received a preset state declaration message from electronic price tag T2, indicating that T2's local cache did not contain any content to be presented, thus G1's ready state was not ready. At 8:56, the server resent the preset message to T2 and simultaneously reassigned G1's presentation time from 9:00 to 6 seconds after 9:00. This time is later than the original presentation time, falls within the 60-second consistency tolerance window, and is different from the presentation time of 2 seconds after 9:00 for group G2 and 4 seconds after 9:00 for group G3.

[0120] In some embodiments, the server sets a preset cutoff point within the lead window. No new delivery time slots are allocated within the remaining time slot after the preset cutoff point. The remaining time slots are used to resend preset messages to electronic price tags that have not received a receipt. The position of the preset cutoff point within the lead window is determined based on the historical preset success rate of the delivery cluster. The time slot after the cutoff point no longer accepts the initial delivery, and therefore resends do not compete with the initial delivery for time slots. The position of the cutoff point is adjusted according to the receipt completion rate in each delivery cluster's previous update tasks. Delivery clusters with high success rates require less resend space and have later cutoff points, while those with low success rates have earlier cutoff points. For electronic price tags whose local cache indicates they have not retained content to be presented based on the preset declaration message, their receipt is no longer considered evidence that the presentation group is ready. The server also resends preset messages to these tags within the remaining time slot. Following the aforementioned scenario, cluster C2 is a weak link and has a historical preset success rate lower than cluster C1. The server sets the preset deadline at 8:53, with the subsequent 7 minutes dedicated to resending.

[0121] Step S6 will be explained below.

[0122] S6. When the presentation conditions of each electronic price tag in the same presentation group are met, the electronic price tag in the group will simultaneously drive its own e-ink screen to display the content to be updated. The presentation conditions include the local timer reaching the presentation time of the presentation group.

[0123] S6 includes sub-steps S61 to S63.

[0124] S61. The local timer of the electronic shelf label generates a comparison match interrupt when the presentation time recorded in the local buffer wakes up the master controller and sets the presentation trigger. The electronic shelf label writes the presentation time given in the preset message into the comparison register bit of the local timer. The timer continues to count in a low-power state. When the count value is equal to the comparison register bit, an interrupt is generated immediately, and the master controller is woken up by this interrupt without waiting for the next cycle wake-up. The cycle wake-up is only used to receive downlink frames and calibrate timing. Its phase is different for each label depending on the arrangement of the downlink cluster. The trigger is given by the comparison match interrupt and is not affected by the phase difference of each label's wake-up. Each electronic shelf label in the same presentation group holds the same presentation time. When the presentation conditions are all met, their drives fall at the same time point, thus aligning the screen switching of the entire group.

[0125] In some embodiments, the local time of the electronic shelf label is provided by its local timer. The electronic shelf label extracts the time base from the downlink broadcast frames periodically sent by the server and uses this time base to calibrate the local timer. The server does not send dedicated time authorization messages to the electronic shelf label. The local timer uses a crystal oscillator for frequency division, and its frequency drifts with temperature and voltage. After accumulating for tens of minutes, a considerable deviation will appear between the local time and the server time, thus causing the triggering times of electronic shelf labels within the same presentation group to be scattered. The server periodically sends downlink broadcast frames carrying timestamps to help the electronic shelf labels maintain network synchronization. When the electronic shelf label receives this frame upon waking, it also extracts the timestamp as a time base and uses it to correct the accumulated deviation of the local timer. The calibration does not occupy additional time slots.

[0126] S62. After the electronic price tag is displayed, check whether the content stored in the local cache is still the version required by the server.

[0127] In some embodiments, S6, the presentation conditions also include passing the pre-presentation verification. After the local time reaches the presentation time, the electronic price tag performs a pre-presentation verification on the validity credentials attached to the content to be updated and displayed in the local cache. If the pre-presentation verification fails, it sends a non-presentation flag back to the server. The passing condition for the pre-presentation verification is that the version number in the validity credentials is consistent with the version number in the most recent preset message received by the electronic price tag, and the local time of the electronic price tag is within the consistency tolerance window.

[0128] The two verification conditions are content and time, respectively. Matching version numbers indicate that the cached version is the one most recently requested by the server; local time is within the consistency tolerance window, meaning the current display still falls within compliance guidelines. If the local timer drifts too much and the trigger falls outside the window, the system will not drive the e-ink display. If either condition is not met, the e-ink display will not drive, and it will continue to display the previous version. The electronic price tag will send a non-display indicator back to the server. Following the aforementioned scenario, the presentation time of presentation group G1, after reallocation, is 6 seconds after 9:00 AM. Electronic price tag T1 is triggered at this time. The version number v2 in its validity certificate is consistent with the version number v2 in the most recently received preset message. The local time falls within the consistency tolerance window of 9:00 AM to 9:01 AM, and the verification passes. Another electronic price tag, after receiving the preset message with version number v2, receives a preset message with version number v3 due to a price change. This message fails to be written to the local cache due to frame corruption. The version number v3 in its header has been registered as the version number of the most recently received preset message. The version number of the display content residing in the cache is still v2. The version number in the certificate is inconsistent with the version number in the most recently received preset message, and the verification fails. This electronic price tag sends back the no-presentation indicator and continues to present the previous version of the display content with version number v1.

[0129] S63. After the presentation conditions are met, the electronic shelf label drives the e-ink screen to display the content to be updated on the screen. The electronic shelf label retrieves the content to be updated from its local cache, applies a voltage sequence to the display medium according to the driving waveform of the e-ink screen model, and the charged particles migrate to the new distribution and remain there after the voltage is removed, thus displaying a new image on the screen. After the driving is completed, the electronic shelf label clears the pending display mark from its local cache, registers the display content as the currently displayed version, and returns to a low-power state. After multiple screen switching, the e-ink screen may retain traces of the previous image, which can be eliminated by the electronic shelf label in an appropriate manner according to existing methods; this method does not limit this.

[0130] In some embodiments, in S6, the electronic shelf label obtains the ambient temperature of the e-ink screen before driving it, and when the ambient temperature is lower than the preset waveform adaptation lower limit temperature, it splits the driving of the e-ink screen into multiple segmented driving sub-processes and executes them sequentially; when the multiple segmented driving sub-processes are not all completed, the electronic shelf label causes the e-ink screen to fall back to the previous version of the display content and sends a failure indicator back to the server.

[0131] The driving waveform is tuned according to the migration characteristics of the display medium at room temperature. As the temperature decreases, the viscosity of the medium increases, resulting in insufficient particle migration driven by the same waveform segment, thus failing to achieve a complete image in a single application. By breaking down the driving process into multiple segmented driving sub-processes, each sub-process applies a short voltage sequence with intervals between sub-processes, allowing particles to migrate to their positions in stages. During segmented execution, the screen is in an intermediate state. If a sub-process is terminated before completion, the screen will remain on an incomplete image. The electronic price tag then retrieves the previous display content from the current frame, re-drives it using the same segmented method to restore the screen to a complete image, and sends back a display failure flag for server registration. The incomplete image is migrated from the previous display content, and the difference between it and the previous display content is smaller than the difference between it and the content to be updated. Based on the aforementioned conversion relationship of estimated refresh time, the number of segmented driving sub-processes required for the fallback is therefore less than that of the forward drive. Following the aforementioned scenario, shelf row R3 is a refrigerated shelf row, and the ambient temperature of the electronic shelf labels on it is -2 degrees Celsius, which is 5 degrees Celsius lower than the preset waveform adaptation lower limit temperature. Four seconds after 9:00, the electronic shelf labels in group G3 split the drive into 3 segmented drive sub-processes and execute them sequentially. After a certain electronic shelf label completes the second sub-process, the ambient temperature of its shelf section further drops to -6 degrees Celsius. The subsequent sub-processes are no longer sufficient to complete the migration according to the currently tuned waveform. The electronic shelf label stops the segmented drive, and its e-ink screen returns to the previous version with version number v1 and sends back a failure indicator.

[0132] The following explains how to determine the display status after presentation.

[0133] As an optional implementation, in S6, after driving the e-ink screen, the electronic price tag sends a presentation receipt back to the server. The presentation receipt contains the version number of the content currently displayed on the e-ink screen.

[0134] The server uses the comparison between the version number in each presentation receipt and the version number of the content to be updated as the criterion for determining whether the display status of each electronic price tag is consistent with the content to be updated, and determines the display status of electronic price tags that have not returned presentation receipts as inconsistent with the content to be updated.

[0135] The presentation receipt is taken from the actual version displayed on the e-ink screen, not from the message delivery result. After the electronic shelf label completes its driver installation, it reads the version number from the current presentation registration item and writes it to the presentation receipt. The server compares this value with the version number of the content to be updated in this update task. If they match, the electronic shelf label's display status is considered consistent with the content to be updated; otherwise, it is considered inconsistent. Electronic shelf labels that have reverted to the previous version of display content due to incomplete segmented driver installation send back a presentation failure flag instead of a presentation receipt, and their display status is determined according to the rules of the next segment.

[0136] Electronic shelf labels that fail to return presentation receipts are considered inconsistent. Missing receipts may stem from driver failure, power outages after driver execution, or lost uplink frames, making it impossible for the server to distinguish. If registered as presented in such cases, the backend record becomes disconnected from the actual shelf display. Electronic shelf labels with a "not presented" or "presentation failed" flag also fall under this rule because they lack a version number matching the content to be updated. By classifying silent labels and the aforementioned two flags as inconsistent, the server ensures that the set of consistent electronic shelf labels held by the server is no larger than the actual set of consistent labels. Continuing with the aforementioned scenario, presentation group G1, after reissue, started the entire group's driver 6 seconds after 9:00 AM. Of its 240 electronic shelf labels, 238 returned presentation receipts with version number v2, matching the version number of the content to be updated, thus their display status was determined to be consistent. Two other labels failed to return presentation receipts, and their display status was determined to be inconsistent with the content to be updated. The server added these two electronic shelf labels to the pending review list.

[0137] The following explains how the endpoint of the consistency tolerance window is presented.

[0138] In some embodiments, before S6, when there is no available presentation time later than the original presentation time within the consistency tolerance window, the server compares the price value in the content to be updated with the price value in the previous version of the content, and determines the presentation method of the presentation group at the end of the consistency tolerance window based on the comparison result.

[0139] When the content to be updated contains a price value and the price value in the content to be updated is lower than the price value in the previous version of the content, the content to be updated is displayed by the electronic price tags in the presentation group that have already sent back receipts, driving their respective e-ink screens to display the content to be updated.

[0140] When the content to be updated does not contain price values ​​or the price values ​​in the content to be updated are not lower than the price values ​​in the previous version of the content, the presentation method is that each electronic price tag in the presentation group maintains the previous version of the content, and the server outputs the identifier of the viewing unit corresponding to the presentation group to the store terminal.

[0141] Combination Figure 4 Presentation times are discretely arranged according to the lower limit of the interval within the consistency tolerance window. Therefore, the number of available time slots is limited. Each reallocation occupies a later time slot, and if the remaining time within the window is less than one lower limit of the interval, there are no more available presentation times. Continuing with the previous scenario, if resending fails, presentation group G1 still has electronic price tags that haven't returned receipts after resending. The server relocates the time slots sequentially, and G1's presentation time is scheduled up to 59.6 seconds after 9:00 AM. Only 0.4 seconds remain between this and the consistency tolerance window's end point of 60 seconds after 9:00 AM, which is less than the 0.6-second lower limit of the interval. Therefore, there are no more presentation times available for reallocation within the window. The end point of the consistency tolerance window is the final processing time for that presentation group. It is not obtained through the presentation time allocation procedure and is not constrained by the lower limit of the interval between adjacent presentation groups. The screen switching for that presentation group is completed no later than this time, and will not be delayed thereafter. The constraint that the presentation time interval between the corresponding presentation groups of adjacent visual units should not exceed the passage time is a constraint of the S3 arrangement stage; the successive redistribution at the end of the consistency tolerance window prioritizes completing the screen switching within the window, at which time the interval can exceed the passage time.

[0142] The two branches diverge according to the direction of the price change. In the case of a price reduction, the cashier has settled at the lower new price from the effective time. The electronic shelf labels that have received receipts will display the new price first, while the remaining electronic shelf labels will retain the old price. Neither of the two prices appearing in the same field of view will be lower than the settlement price. Regardless of which electronic shelf label the customer expects, the actual payment will not be higher than the price seen. Continuing from the previous scenario, the price value in the content to be updated in version v2 is 8.90 yuan, and the price value in the previous version of the content to be updated in version v1 is 12.80 yuan. Since 8.90 yuan is lower than 12.80 yuan, the cashier will settle at 8.90 yuan from 9:00 AM. The electronic shelf labels in display group G1 that have received receipts will drive their respective e-ink screens to display the content to be updated in version v2 at the end of the consistency tolerance window. Electronic shelf labels that do not have the content to be updated resident in the local cache will continue to display the previous version of the content to be updated in version v1.

[0143] In cases of price increases or the absence of price values, the entire display remains the old version. Since the change took effect, the checkout has been settling transactions at the higher new price. Electronic shelf labels that haven't yet been updated show an old price lower than the settlement price, leading customers to expect the higher price upon seeing it. If, in this situation, the already-received electronic shelf labels are shown with the new price, the discrepancy remains, and two prices will still appear simultaneously within the same field of view. Maintaining the previous display content for the entire group ensures price consistency within that view unit. The server outputs the identifier of the view unit corresponding to the display group to the store terminal, allowing staff to manually verify the information by locating the specific shelf section. This reduces the discrepancy to a single view unit. When the updated display content doesn't contain price values, the change is unrelated to the settlement price, and phased updates do not involve discrepancies between the displayed price and the settlement price. In another update task in the same scenario, when the price value in the content to be updated is 15.80 yuan and not lower than 12.80 yuan in the previous version of the content, each electronic price tag in the presentation group G1 still displays the previous version of the content at the end of the consistency tolerance window, and the server outputs the identifier of the view unit V1 to the store terminal.

[0144] The following section explains the module mapping between the server and the electronic price tag using this method.

[0145] The server-side includes an update task orchestration module, a cluster grouping module, a time-based scheduling module, a message sending module, and a status aggregation module. The update task orchestration module is configured to execute S1, obtaining the content to be updated and the effective time for each electronic price tag and assigning a version number. The cluster grouping module is configured to execute S2, dividing the distribution clusters according to the access base station and link quality, and dividing the presentation groups according to the field of view unit. The time-based scheduling module is configured to execute S3, arranging the distribution time slots within the lead window and the presentation time slots within the consistency tolerance window, and verifying the order of the two. The message sending module is configured to execute S4, sending preset messages within the distribution time slots. The status aggregation module is configured to receive reception receipts and presentation receipts, determine the readiness status of the presentation groups and the display status of each electronic price tag, and reallocate presentation time slots or arrange re-issuance when necessary.

[0146] The electronic price tag includes a message receiving module, a cache resident module, and a display driver module. The message receiving module is configured to receive preset messages, canceled messages, and resent messages within the wake-up window; the cache resident module is configured to execute S5, write the content to be updated to the local cache, and maintain the original image of the e-ink screen during the resident period; the display driver module is configured to execute S6, set the presentation trigger according to the comparison matching interrupt generated by the local timer at the presentation time, perform pre-presentation verification and drive the e-ink screen, execute segmented driving sub-processes at low temperatures, and fall back to the previous version of the display content in the same segmented manner if not fully completed.

[0147] The same or similar parts in the various embodiments of this application can be referred to each other, and the technical features of each embodiment can be combined with each other to form new embodiments without conflict.

[0148] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device / system can be divided into different functional units or modules to complete all or part of the functions described above.

[0149] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for dynamic pricing and information updating of e-ink electronic price tags, characterized in that, The steps are as follows: S1. The server obtains the content to be updated for each electronic price tag and the effective time of the content to be updated; S2. The server divides each electronic shelf label into a distribution cluster according to the link quality between the access base station to which each electronic shelf label belongs and each electronic shelf label, and divides them into presentation groups independently according to the field of view unit where each electronic shelf label is located. The field of view unit is a shelf area that can be observed simultaneously at a single observation station. S3. The server allocates non-overlapping distribution time periods for each distribution cluster within the lead time window before the effective time, and allocates different presentation times for each presentation group within a preset consistency tolerance window calculated from the effective time. The presentation time of each presentation group is later than the distribution time period of the distribution cluster to which all electronic price tags in the presentation group belong. S4. The server sends a preset message to the electronic price tag in the distribution cluster during the distribution period. The preset message includes the content to be updated and the presentation time of the presentation group to which it belongs. S5. The electronic shelf label receives the preset message and writes the content to be updated to the local cache. The e-ink screen of the electronic shelf label continues to display the previous version of the content while the content to be updated resides in the local cache. S6. When their respective presentation conditions are met, each electronic price tag in the same presentation group simultaneously drives its own e-ink screen to display the content to be updated. The presentation conditions include the local time reaching the presentation time of the presentation group to which the tag belongs.

2. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 1, characterized in that, In step S5, after the content to be updated is written to the local cache, the electronic shelf label sends a receipt back to the server. The receipt includes the version number of the content to be updated received by the electronic shelf label, wherein each version of the content has a version number. Before step S6, the server determines the ready state of the presentation group based on the receipts of each electronic shelf label in the presentation group. The condition for the ready state to be ready is that all electronic shelf labels in the presentation group have sent back the receipt and the version number in each receipt is consistent. For presentation groups whose ready state is not ready, the server reallocates a presentation time later than the original presentation time and sends it to each electronic shelf label in the presentation group. The reallocated presentation time is within the preset consistency tolerance window and is different from the presentation time of each presentation group.

3. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 2, characterized in that, Before step S6, if there is no available presentation time later than the original presentation time within the preset consistency tolerance window, the server compares the price value in the content to be updated with the price value in the previous version of the content, and determines the presentation mode of the presentation group at the end of the preset consistency tolerance window based on the comparison result. Specifically, if the content to be updated contains a price value and the price value in the content to be updated is lower than the price value in the previous version of the content, the presentation mode is that the electronic shelf labels within the presentation group that have already sent back the receipt drive their respective e-ink screens to present the content to be updated. If the content to be updated does not contain a price value or the price value in the content to be updated is not lower than the price value in the previous version of the content, the presentation mode is that each electronic shelf label within the presentation group maintains the presentation of the previous version of the content, and the server outputs the identifier of the viewing unit corresponding to the presentation group to the store terminal.

4. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 2, characterized in that, In step S6, after driving the e-ink screen, the electronic price tag sends a presentation receipt back to the server. The presentation receipt contains the version number of the content currently displayed on the e-ink screen. The server uses the comparison result between the version number in each presentation receipt and the version number of the content to be updated as the criterion for determining whether the display status of each electronic price tag is consistent with the content to be updated. The server also determines that the display status of electronic price tags that have not sent back the presentation receipt is inconsistent with the content to be updated.

5. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 2, characterized in that, In response to the electronic price tag recovering from a power outage that occurred after S5 before the effective time, the electronic price tag proactively reports a preset state declaration message to the server. The preset state declaration message includes whether the content to be updated to be displayed is stored in the local cache and the version number of the content to be updated to be displayed. When the preset state declaration message indicates that the content to be updated to be displayed is not stored in the local cache, or that the version number of the content to be updated to be displayed is inconsistent with the current version number of the content to be updated to be displayed, the server updates the ready state of the presentation group to which the electronic price tag belongs to to not ready. During the remaining time period of the lead time window, the server allocates a reissue time point for the electronic price tag that does not overlap with each of the issuance time periods, and reissues the preset message to the electronic price tag at the reissue time point.

6. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 2, characterized in that, In step S4, the preset message further includes a validity credential, which includes the effective time and the version number of the content to be updated; in step S6, the presentation condition further includes passing the pre-presentation verification. After the local timer reaches the presentation time, the electronic price tag performs the pre-presentation verification on the validity credential attached to the content to be updated stored in the local cache, and sends a non-presentation flag back to the server if the pre-presentation verification fails. The passing condition for the pre-presentation verification is that the version number in the validity credential is consistent with the version number in the most recent preset message received by the electronic price tag, and the local time of the electronic price tag is within the preset consistency tolerance window.

7. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 6, characterized in that, In step S6, the electronic price tag obtains the ambient temperature of the e-ink screen before driving it, and when the ambient temperature is lower than the preset waveform adaptation lower limit temperature, it splits the driving of the e-ink screen into multiple segmented driving sub-processes and executes them sequentially; when the multiple segmented driving sub-processes are not all completed, the electronic price tag causes the e-ink screen to fall back to the previous version of the display content and sends a failure indicator back to the server.

8. The method for dynamic pricing and information updating of e-ink electronic price tags according to claim 1, characterized in that, In step S3, the interval between the presentation times of the presentation groups corresponding to two adjacent visual fields is no greater than the travel time determined by a preset movement rate from the observation station of one visual field to the observation station of the adjacent visual field. After step S3 and before step S4, the server will adjust the electronic price tags that are located at the boundary of two adjacent visual fields and can be observed at the observation stations of the two adjacent visual fields to be assigned to the presentation group with the earlier presentation time in the presentation groups corresponding to the two adjacent visual fields.

9. The method for dynamic pricing and information updating of e-ink electronic price tags according to claim 1, characterized in that, In step S1, the server further determines the estimated refresh time of the content to be updated based on the area of ​​the difference region between the content to be updated and the previous version of the electronic price tag recorded by the server, and the position of the difference region in the content to be updated. In step S3, the server determines the lower limit of the interval between the presentation times of two adjacent presentation groups based on the maximum value of the estimated refresh times of each electronic price tag in the presentation group, and determines the duration of the distribution period allocated to the distribution group based on the sum of the data volume of the content to be updated of each electronic price tag in the distribution cluster.

10. The dynamic pricing and information updating method for e-ink electronic price tags according to claim 1, characterized in that, In step S2, the server divides the distribution clusters based on the wake-up phase of each electronic price tag, and the wake-up phases of each electronic price tag within the same distribution cluster fall into the same wake-up window; in step S4, the preset message also includes a wake-up phase offset, and the wake-up phase offset, the content to be updated, and the presentation time are carried in the same preset message, and are determined based on the distribution time period pre-scheduled by the server for the next update task; in step S5, the electronic price tag adjusts its wake-up phase based on the wake-up phase offset.

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