JP2011108139A - Data synchronization system, memory module, and data synchronization method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new data synchronization system for directly synchronizing data between memory cards. <P>SOLUTION: The data synchronization system includes a first memory module having a first memory and a second memory module having a second memory. The first memory module includes: a data storage means for storing the data received from external equipment in the first memory; a first establishment means for establishing a wireless communication path to the second memory module; a determination means for determining whether to update the data stored in the second memory by the data stored in the first memory; and a data transmission means for transmitting the data stored in the first memory to the second memory module when data update is determined. The second memory module includes: a second establishment means for establishing a wireless communication path with the first memory; and a data update means for updating, on the basis of the received data, the data stored in the second memory. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a data synchronization system, a memory module, and a data synchronization method.

  Conventionally, when trying to synchronize (share) data stored in a memory module (for example, a small memory card such as an SD card) with data stored in another memory card, A method of synchronizing data is generally used. Specifically, the copy source memory card or the copy destination memory card is inserted into the interface slot of the information processing apparatus, and the data stored in the copy source memory card is temporarily stored in the information processing apparatus. In this method, data stored in a processing device is copied to a copy destination memory card to synchronize the data.

  In addition to inserting the memory card into the interface slot of the information processing apparatus, as in the technique described in Patent Document 1, the IC card (memory card) is equipped with a wireless function, and the IC card and the information processing apparatus are There is also a method of performing data communication by wireless communication.

Japanese Unexamined Patent Publication No. 2000-91984

  However, the conventional data synchronization method is based on the premise that data communication is performed via an information processing device when data is synchronized between memory cards. There was a problem that it was not possible to synchronize.

  Moreover, even if there is an information processing device, the user has to be aware of various settings for the information processing device for each memory card, which often lacks convenience.

  In particular, in a method in which a memory card is equipped with a wireless function and data communication is performed between the memory card and the information processing device by wireless communication, when all the memory cards are within a range where wireless communication can be performed with the information processing device. However, data synchronization cannot be performed, and the problem of lack of convenience becomes significant.

  Accordingly, an object of the present invention is to solve the above problems and provide a new data synchronization system, data synchronization method, and memory module that can directly synchronize data between memory cards.

  A data synchronization system according to an aspect of the present invention includes a first memory module having a first memory and a second memory module having a second memory, and synchronizes data stored in the first memory and the second memory. Data synchronization system. The first memory module is connected by wireless communication between the first data storage means for storing data received from the first external device connected to the first memory module in the first memory and the second memory module. The first establishment means for establishing the wireless communication path and the memory information of the data stored in the second memory via the wireless communication path are received and stored in the first memory based on the received memory information First determination means for determining whether or not to update data stored in the second memory with data, and updating data stored in the second memory with data stored in the first memory by the first determination means A first data transmission unit configured to transmit the data stored in the first memory to the second memory module via the wireless communication path when determined. The second memory module connects to the first memory module by wireless communication, establishes a wireless communication path, and stores data stored in the second memory via the wireless communication path. Memory information transmitting means for transmitting memory information to the first memory module, and data is received from the first data transmitting means of the first memory module via the wireless communication path, and stored in the second memory based on the received data Data updating means for updating the read data and data reading means for reading the data stored in the second memory.

  The first memory module also includes a memory information transmitting means for transmitting memory information of data stored in the first memory to the second memory module via the wireless communication path, and a second memory module from the second memory module via the wireless communication path. Data updating means for receiving data and updating data stored in the first memory based on the received data; reading means for reading data stored in the first memory; and first data by the first data storage means First protection means for protecting storage of data in the memory can be further provided. On the other hand, the second memory module has second data storage means for storing data received from a second external device connected to the second memory module, and data stored in the first memory via a wireless communication path. Second determination means for receiving the memory information and determining whether to update the data stored in the first memory with the data stored in the second memory based on the received memory information; 2nd data transmission which transmits the data memorize | stored in 2nd memory via the wireless communication path to the 1st memory module, when it determines with updating the data memorize | stored in 1st memory with the data memorize | stored in 2 memory And a second protect means for protecting the storage of data in the second memory by the second data storage means. When the first data storage means receives data from the first external device, the first data storage means transmits a protection setting notification for causing the second protection means to execute protection to the second memory module, and the second memory module notifies the protection setting notification. After receiving the response notification to, the data received from the first external device is stored in the first memory. In addition, when the second data storage unit receives data from the second external device, the second data storage unit transmits a protection setting notification for causing the first protection unit to execute protection to the first memory module, and the protection setting notification from the first memory module. After receiving the response notification to, the data received from the second external device is stored in the second memory.

  Further, the second memory module stores second data storage means for storing data received from the second external device connected to the second memory module, and stores data in the second memory by the second data storage means. Second protection means for protecting may further be provided. When the first data storage means receives data from the first external device, the first data storage means transmits a protection setting notification for causing the second protection means to execute protection to the second memory module, and a response notification to the protection setting notification from the second memory module. Is received, the data received from the first external device is stored in the first memory.

  The first memory further includes a data storage buffer and a data synchronization buffer. The first data storage means stores the data received from the first external device in the data storage buffer, and the data stored in the data storage buffer is a predetermined data. It is also possible to provide means for replicating the data synchronization buffer at the timing. The first determination means determines whether or not to update the data stored in the second memory with the data stored in the data synchronization buffer, and the first data transmission means stores the data in the data synchronization buffer by the first determination means. If it is determined to update the data stored in the second memory with the processed data, the data stored in the data synchronization buffer is transmitted to the second memory module.

  Further, the second memory includes a first buffer and a second buffer, and the data updating means designates one of the first buffer and the second buffer as an update buffer and the other as a read buffer; Means for updating the data stored in the update buffer based on the data received from the first data transmission means, and means for switching the buffer designated as the update buffer and the read buffer for each data update. it can. The first determination means determines whether or not the data stored in the buffer designated as the update buffer is updated with the data stored in the first memory, and the first data transmission means is the first determination means. When it is determined that the data stored in the buffer designated as the update buffer is updated with the data stored in the first memory, the data stored in the first memory is transmitted to the second memory module.

  Further, a plurality of second memory modules may be provided.

  Further, each of the plurality of second memory modules receives memory information of data stored in another second memory of another second memory module via a wireless communication path, and based on the received memory information Second determination means for determining whether or not to update data stored in another second memory with data stored in its own second memory, and stored in its own second memory by the second determination means When it is determined to update the data stored in the other second memory with the data, the second data transmission that transmits the data stored in its own second memory to the other second memory module via the wireless communication path Means. The second establishing means establishes a wireless communication path by establishing a wireless communication path with another second memory module, and the memory information transmitting means stores the memory information in its own second memory via the wireless communication path. The memory information of the received data is transmitted to the other second memory module, and the data updating means receives the data from the second data transmitting means of the second memory module via the wireless communication path, and based on the received data The data stored in its second memory is updated.

  A memory module according to an aspect of the present invention is based on wireless communication between a first memory that stores data, a data storage unit that stores data received from an external device in the first memory, and a memory module that is a data synchronization target. Establishing means for establishing a connection and establishing a wireless communication path, and receiving memory information of data stored in the second memory of the memory module subject to data synchronization via the wireless communication path, and based on the received memory information Determining means for determining whether or not to update the data stored in the second memory with the data stored in the first memory; and when the determining means determines that the data is to be updated, Data transmitting means for transmitting stored data to a memory module subject to data synchronization, and data from the memory module subject to data synchronization via a wireless communication path Receiving the data, and a data updating means for updating the data stored in the first memory based on the data thus received.

  A data synchronization method according to an aspect of the present invention includes a first memory module having a first memory and a second memory module having a second memory, and synchronizes data stored in the first memory and the second memory. A data synchronization method, wherein a first memory module stores data received from a first external device connected to the memory module in a first memory, and the first memory module and the second memory module include: Establishing a wireless communication path by establishing a wireless communication connection, and transmitting a memory information of data stored in the second memory to the first memory module via the wireless communication path. The first memory module receives the memory information and stores it in the second memory with the data stored in the first memory based on the received memory information. Determining whether or not to update the data, and if the first memory module determines to update the data stored in the second memory with the data stored in the first memory, via the wireless communication path Transmitting the data stored in the first memory to the second memory module, and the data stored in the second memory based on the data received from the first memory by the second memory module via the wireless communication path. Updating.

It is a figure which shows an example of schematic structure of the data synchronization system 1 of 1st Embodiment. It is a flowchart which shows the processing content of the data synchronization method of 1st Embodiment. It is a figure which shows the application example of 1st Embodiment. It is a figure which shows an example of schematic structure of the data synchronization system 2 of 2nd Embodiment. It is a flowchart which shows the processing content of the data synchronization method of 2nd Embodiment. It is a figure for demonstrating the 1st memory 21A of 3rd Embodiment. It is a flowchart which shows the processing content of the data synchronization method 3 of 3rd Embodiment. It is a figure for demonstrating the 2nd memory 21B of 4th Embodiment. It is a flowchart which shows the processing content of the data synchronization method 4 of 4th Embodiment. It is a figure which shows the example of application of this embodiment. It is a figure which shows the example of application of this embodiment.

Hereinafter, each preferred embodiment for carrying out the present invention will be described with reference to the drawings. In each embodiment, a case where data synchronization is performed between two pairs of memory modules will be described as an example. As an example of a memory module, a memory card (for example, an SD memory card (registered trademark) or the like) Card).
<First Embodiment>

  FIG. 1 is a diagram showing an example of a schematic configuration of a data synchronization system 1 according to the first embodiment of the present invention.

  As shown in FIG. 1, the data synchronization system 1 includes a first external device 10A, a second external device 10B, and a pair of first memory card 20A and second memory card 20B.

  The first external device 10A has a card slot for connecting the first memory card 20A, and reads data from a first memory (first storage means) included in the first memory card 20A connected to the card slot. Means and writing means for writing data into the first memory. Similar to the first external device 10A, the second external device 10B has a card slot for connecting the second memory card 20B, and a second memory (second memory) included in the second memory card 20B connected to the card slot. (2 storage means) and reading means for reading data from the storage means, and writing means for writing data to the second memory. The first external device 10A and the second external device 10B supply power necessary for data writing and wireless communication to the connected first memory card 20A and second memory card 20B, respectively. Note that the first external device 10A and the second external device 10B can be general devices (for example, a digital camera, a mobile phone, a printer device, or a computer) that can read and write data in a memory card. Detailed description of the configuration and function is omitted.

  Since the first memory card 20A and the second memory card 20B in the present embodiment can mutually have the same configuration and function, the configuration and function of the first memory card 20A will be described below. Description of the card 20B is omitted.

  As shown in FIG. 1, the first memory card 20A (first storage medium) includes a first memory 21A, a first data storage unit 22A, a first establishment unit 23A, a first determination unit 24A, a first data transmission / reception unit 25A, First data updating means 26A and first data reading means 27A are provided. The first data storage unit 22A, the first establishment unit 23A, the first determination unit 24A, and the first data transmission / reception unit 25A are functions used when the first memory card 20A is a copy source memory card, The first establishing means 23A, the first data transmitting / receiving means 25A, the first data updating means 26A, and the first data reading means 27A are functions that are used when the first memory card 20A is a copy destination memory card. is there. Each of the above means is realized by a controller (processing circuit) mounted on the memory card. In addition, the standard / shape of the first memory card 20A can be based on the standard / shape of a memory card existing in the past.

  The first memory 21A is a memory for storing data, for example, a non-volatile flash memory. In the first memory 21A, data is stored by the first data storage means 22A. The first memory 21A stores in advance various data for performing wireless communication with the second memory card 20B paired with the first memory card 20A.

  The first data storage unit 22A stores the data received from the first external device 10A connected to the first memory card 20A in the first memory 21A. That is, the first data storage unit 22A receives a data write command (WRITE command) from the first external device 10A, and stores the data received from the first external device 10A in the first memory 21A. Note that the first data storage unit 22A can store, for example, information on the time (data update time) at which data is stored in the first memory 21A as memory information.

  The first establishing means 23A establishes a wireless communication path by performing peer-to-peer connection by wireless communication with the second memory card 20B, and is connected to the second establishing means 23B of the second memory card 20B. Data communication necessary for peer-to-peer connection is performed mutually. Specifically, the first establishment unit 23A establishes a peer-to-peer connection with the second establishment unit 23B, for example, triggered by the data stored in the first memory 21A by the first data storage unit 22A. Is transmitted toward the periphery of the first memory card 20A. When the second memory card 20B exists in a range where wireless communication is possible, the second establishing means 23B of the second memory card 20B receives the connection signal and transmits a response signal to the first memory card 20A. To do. Then, the first establishment unit 23A receives the response signal, and authenticates whether the response signal belongs to the second memory card 20B. Further, the first establishing means 23 can exchange an encryption key with the second establishing means 23B at the time of connection. The establishment of a wireless communication path between the first establishment means 23 and the second establishment means 23B is realized using a conventional wireless communication technology (for example, standardized technology such as IEEE 802.11). Therefore, detailed description is omitted.

  The first determination unit 24A determines whether or not to update the data stored in the second memory 21B with the data stored in the first memory 21A based on the memory information received from the second memory card 20B. Specifically, the first determination unit 24A compares the update time of the data in the second memory included in the received memory information with the update time of the data in the first memory 21A, and the data in the first memory 21A. Is updated more recently than the data update time of the second memory 21B, it is determined that the data of the second memory 21B is updated. The first determination unit 24A is not limited to the case where the data update time is used as the memory information. For example, a checksum value may be used.

  The first data transmitting / receiving unit 25A transmits / receives data to / from the second data transmitting / receiving unit 25B of the second memory card 20B via a wireless communication path. When it is determined that the data stored in the second memory 21B is updated with the data stored in the first memory 21A by the first determination unit 24A, the first data transmitting / receiving unit 25A stores the data stored in the first memory 21A. Is received as a data transmission means for transmitting data to the second memory card 20B, and receives data transmitted from the first external device 10A and data transmitted from the data transmission / reception means 25B of the second memory card 20B. Functions as a means.

  The first data updating unit 26A receives data from the second data transmitting / receiving unit 25B of the second memory card 20B, and updates the data stored in the first memory 21A based on the received data. For example, the first data updating unit 26A may update the data by rewriting all the data, or may update the data only at a place where the data has been changed.

  The first data reading means 27A receives a data reading command from the first external device 10A connected to the first memory card 20A, acquires the corresponding data from the first memory 21A, and sends it to the first external device 10A. send.

  Hereinafter, the data synchronization method of this embodiment implemented using the data synchronization system 1 is demonstrated with reference to the flowchart shown in FIG. Hereinafter, the case where data is received from the connected first external device 10A in the first memory card 20A will be described as an example. Note that the processes shown in the flowchart of FIG. 2 can be executed in any order or in parallel as long as the process contents do not contradict each other.

  First, in the first memory card 20A, the data received from the connected first external device 10A is stored in the first memory 21A (step S100). At the same time, the first memory card 20A stores time information (data update time) at which data is stored in the first memory 21A as one of the memory information. The time information can be acquired from the first external device 10A.

  Next, the first memory card 20A establishes a peer-to-peer connection by wireless communication with the second memory card 20B to establish a wireless communication path (step S101). Specifically, the first memory card 20A sends a connection signal for peer-to-peer connection with the second memory card 20B around the first memory card 20A, triggered by the storage of data in the first memory 21A. The communication channel can be established by receiving the response signal from the second memory card 20B. If the wireless communication path is not established (step S102: No), the process returns to step S101.

  When the wireless communication path is established (step S102: Yes), the second memory card 20B transmits the memory information of the data stored in the second memory 21B to the first memory card 20A via the wireless communication path, and The one memory card 20A receives the memory information of the data in the second memory 21B (step S103).

  In the first memory card 20A, it is determined whether or not to update the data stored in the second memory 21B with the data stored in the first memory 21A (step S104). For example, the determination can be made using information such as the update time of data included in the memory information held by each of the first memory 21A and the second memory 21B.

  When it is determined to update (step S105: Yes), in the first memory card 20A, the data stored in the first memory 21A is transmitted to the second memory card 20B (step S106). For example, when the data update time included in the memory information of the data in the first memory 21A is more recent than the data update time included in the memory information of the data in the second memory 21B, in the first memory card 20A, The data stored in the first memory 21A is transmitted to the second memory card 20B.

  Next, the second memory card 20B receives data from the first memory 21A, updates the data stored in the second memory 21B based on the received data (step S107), and proceeds to the process of step S103. At the same time, the second memory card 20B also stores the time information at which the data is stored in the second memory 21B. The time information can be acquired from the second external device 10B.

  Further, in the process of step S105, when it is determined not to update (step S105: No), this process flow ends.

  As described above, according to the data synchronization system and the data synchronization method of the first embodiment, each memory card (memory module) that performs data synchronization includes peer-to-peer connection by wireless communication and establishes a wireless communication path. The data stored in the memory of the card can be used as a trigger to automatically update data in another memory card that is a pair, and data synchronization can be performed without using an information processing apparatus. As a result, compared to the conventional data synchronization system and data synchronization method, there are fewer requests for understanding, setting, and operation for the user, and convenience is improved.

As an example of the data synchronization system according to the first embodiment, for example, as shown in FIG. 3, one of the paired memory cards is connected to a digital camera and the other is connected to a printer device. In this case, when shooting is performed with a digital camera and data is stored in the memory card, the data stored in the memory card connected to the printer device is automatically updated using the data storage as a trigger. The printer device can detect the data change in the memory card and execute printing of the captured images one by one. This is particularly effective in cases where it is desired to hand over the photographed image immediately to the attendee, such as at a wedding.
Second Embodiment

  The data synchronization system 2 according to the second embodiment of the present invention will be described below. FIG. 4 is a diagram illustrating an example of a schematic configuration of the data synchronization system 2 of the second embodiment.

  In the first embodiment, before data is synchronized between two pairs of the first memory card 20A and the second memory card 20B, for example, in the first memory card 20A and the second memory card 20B, the data When writing is performed, when data is synchronized, data written to the memory in any memory card may be lost. Therefore, in the data synchronization system 2 of the second embodiment, when data is written to one memory card, the data writing is not performed at the same time by protecting the data writing on the other memory card. The purpose is to be.

  In addition, in each means which comprises the data synchronous system 2, the description which a means which can be made common with the structure of the data synchronous system 1 of 1st Embodiment is abbreviate | omitted. Further, since the first memory card 20A ′ and the second memory card 20B ′ can have the same configuration and function, the configuration and function of the first memory card 20A ′ will be described below.

  When receiving data from the first external device 10A, the first data storage unit 22A ′ transmits a protection setting notification (lock command) to the second memory card 20B ′, and sets the protection from the second memory card 20B ′. After receiving the response notification to the notification, the data received from the first external device 10A is stored in the first memory 21A ′.

  The first protect means 28A protects the storage of data in the first memory 21A. Specifically, when the protect setting notification is received from the second memory card 20B, the storage of data in the first memory 21A is protected. Further, after the protection, a response notification is transmitted to the first memory card 20A, and after the data is updated by the first data updating means 26A, the protection is released. That is, the protect means 28A does not cancel the protect setting until the data stored in the first memory 21A matches the data stored in the second memory 21B, and is connected to the first memory card 20A during that time. Act as “write protection” for the first external device 10A.

  Hereinafter, the data synchronization method of this embodiment implemented using the data synchronization system 2 is demonstrated with reference to the flowchart shown in FIG. Hereinafter, a data synchronization method when data is received from the connected first external device 10A in the first memory card 20A will be described as an example. Note that the processes shown in the flowchart of FIG. 5 can be executed in any order or in parallel as long as the process contents do not contradict each other.

  First, the first memory card 20A receives data from the first external device 10A (step S200).

  Next, in the first memory card 20A, a peer-to-peer connection is established by wireless communication with the second memory card 20B to establish a wireless communication path (step S201). Specifically, the first memory card 20A sends a connection signal for peer-to-peer connection with the second memory card 20B around the first memory card 20A, triggered by the reception of data to the first memory 21A. The communication channel can be established by receiving the response signal from the second memory card 20B. If the wireless communication path has not been established (step S202: No), the process returns to step S201.

  When the wireless communication path is established (step S202: Yes), the first memory card 20A transmits a protection setting notification to the memory card 20B (step S203).

  Next, the memory card 20B receives the protection setting notification and executes the protection setting, and transmits a response notification to the protection setting notification to the memory card 20A (step S204). While the memory card 20B is protected, data writing from the second external device 10B connected to the memory card 20B is prohibited (“write protection”).

  When the memory card 20A receives the response notification (step S205: Yes), the data received from the first external device 10A is stored in the first memory 21A (step S206).

  Next, the processing proceeds to step S207 and subsequent steps, but the processing in steps S207 to S211 can be the same as the processing in steps S103 to S107 in the flow of the data synchronization method of the first embodiment shown in FIG. Detailed description here is omitted.

  After the processing in step S211, the protection setting is canceled in the memory card 20B (step S211).

  As described above, according to the data synchronization system of the second embodiment, a memory card that has been instructed to write data after receiving data from an external device transmits a protect setting notification to the other memory card in the pair. Prohibits writing data by external devices with memory card. Accordingly, data is not simultaneously written in the paired memory cards, and data written to any memory card by an external device can be prevented from being lost when data is synchronized. .

In the data synchronization system of the second embodiment, the case where the protection setting notification is transmitted when data is received from the first external device 10A has been described as an example. However, the present invention is not limited to this. When writing is desired, the user may protect the memory card not to be written from an external device connected to the memory card. Alternatively, a physical switch for prohibiting writing may be provided in the memory card.
<Third Embodiment>

  The data synchronization system 3 according to the third embodiment of the present invention will be described below.

  The writing of data to the memory card by the external device can be configured by, for example, a plurality of write commands instead of a single write command (WRITE command). In this case, every time a data write command is received, if data is transmitted to another pair of memory cards, the throughput is greatly affected. Therefore, the data synchronization system according to the third embodiment aims to suppress the influence on the throughput by configuring the memory in the memory card as a double buffer configuration including a data update buffer and a data synchronization buffer.

  In addition, in each means which comprises the data synchronization system 3, the description of the means which can be made common with the structure of the data synchronization system 1 of 1st Embodiment is abbreviate | omitted. Since the memory card 20A and the memory card 20B can have the same configuration and function, the configuration and function of the memory card 20A will be described below.

  The first memory 21A includes a data update buffer and a data synchronization buffer. The data update buffer is a buffer for storing the received data in the memory by the first data storage means 22A. The data synchronization buffer is used by the first determination unit 24A to determine whether or not the data stored in the data synchronization buffer updates the data stored in the second memory 21B included in the second memory card 20B. Buffer.

  The first data storage unit 22A stores the data received from the first external device 10A in the data storage buffer, and copies the data in the data storage buffer to the data synchronization buffer at a predetermined timing. FIG. 6 shows a schematic diagram of the double buffer configuration of the first memory 21A ′ of the present embodiment. For example, FIG. 6A shows a state where a write command is received and data is stored in the data update buffer, and FIG. 6B shows a state where data in the data update buffer is copied to the data synchronization buffer. Here, the predetermined timing is, for example, a timing at which a data write command is not received from an external device for a certain period of time. Note that the predetermined timing is not limited to the above timing, and may be a timing according to a user instruction, for example.

  The first determination unit 24A determines whether or not to update the data stored in the second memory 21B with the data stored in the data synchronization buffer.

  When the data transmitting / receiving unit 25A determines to update the data stored in the second memory 21B with the data stored in the data synchronization buffer by the first determination unit 24A, the data transmitting / receiving unit 25A stores the data stored in the data synchronization buffer in the second memory Send to card 20B.

  Hereinafter, the data synchronization method of this embodiment implemented using the data synchronization system 3 is demonstrated with reference to the flowchart shown in FIG. Hereinafter, a description will be given of a data synchronization method when data is received from the connected external device 10A in the first memory card 20A as an example. In addition, each process shown by the flowchart of FIG. 7 can be arbitrarily changed in order within the range which does not produce contradiction in the processing content, or can be performed in parallel.

  First, in the memory card 20A, the data received from the external device 10A is stored in the data update buffer of the first memory 21A (step S300).

  Next, in the first memory card 20A, peer-to-peer connection is established by wireless communication with the memory card 20B, and a wireless communication path is established (step S301). When the wireless communication path is not established (step S302: No), the process returns to step S301.

  When the wireless communication path is established (step S302: Yes), the second memory card 20B transmits the memory information of the data stored in the second memory 21B to the first memory card 20A via the wireless communication path. The first memory card 20A receives the memory information of the data in the second memory 21B (step S303).

  In the first memory card 20A, it is determined whether or not to update the data stored in the second memory 21B with the data stored in the data synchronization buffer (step S304).

  When it is determined to update (step S305: Yes), in the first memory card 20A, the data stored in the data synchronization buffer of the first memory 21A is transmitted to the second memory card 20B (step S306).

  In the second memory card 20B, the data stored in the second memory 21B is updated based on the received data (step S307). Next, the process proceeds to step S304.

  Further, in the process of step S305, if it is not updated (step S305: No), and there is no write command from an external device for a certain period of time in the first memory card 20A (step S308: Yes), the data storage buffer Are copied to the data synchronization buffer (step S309), and the data stored in the data storage buffer and the data synchronization buffer are matched. After the process of step S309, or when there is a write command from an external device (step S308: No), the process proceeds to step S304.

As described above, according to the data synchronization system 3 and the method of the third embodiment, the memory of the memory card includes the data storage buffer and the data synchronization buffer, stores the data received from the external device in the data storage buffer, By performing data synchronization with the memory card with the data synchronization buffer, it is not affected by data storage during data synchronization, so it suppresses frequent data updates and has an impact on throughput. Can be suppressed.
<Fourth embodiment>

  The data synchronization system 4 according to the fourth embodiment of the present invention will be described below.

  The wireless communication used in the above embodiment may cause the wireless communication between the memory cards to be cut off due to factors such as movement of an external device, and if this occurs during data transmission / reception between the memory cards, There is a risk of data loss in the memory card. In order to prevent this, the data synchronization system 4 of the fourth embodiment has a double buffer configuration for “reading” and “for updating” in the memory means in the memory card, and aims to suppress data loss in the memory card. It is said.

  In addition, in each means which comprises the data synchronization system 4, the description of the means which can be made common with the structure of the data synchronization system 1 of 1st Embodiment is abbreviate | omitted. Moreover, since the first memory card 20A and the second memory card 20B can have the same configuration and function, the configuration and function of the first memory card 20A will be described below.

  The first memory 21A includes a first buffer and a second buffer. One of the first buffer and the second buffer is designated as an update buffer by the first data updating means 26A, and the other is designated as a read buffer. The buffer designated as the update buffer is a buffer for updating the data in the first memory based on the received data by the data updating means 26A. The buffer designated as the read buffer is not updated by the data updating unit 26A, and is, for example, a buffer for providing data stored in the buffer to the user via the external device 10A.

  The first data updating means 26A designates one of the first buffer and the second buffer as an update buffer and designates the other as a read buffer, and updates the data based on the data received from the first memory card 20A. The data stored in the buffer is updated, and the buffer designated as the update buffer and the read buffer is switched for each data update. FIG. 8 shows a schematic diagram of a double buffer configuration of the first memory 21A of the present embodiment. For example, as shown in FIG. 8A, the first buffer is designated as a read buffer, and the second buffer is designated as an update buffer. Then, after the data update based on the received data is completed in the update buffer, as shown in FIG. 8B, the first buffer is designated as the update buffer and the second buffer is designated as the read buffer. .

  The first determination unit 24A determines whether or not to update the data stored in the buffer designated as the update buffer with the data stored in the first memory 21A.

  When it is determined that the first data transmission unit 25A updates the data stored in the buffer designated as the update buffer with the data stored in the first memory 21A by the first determination unit 24A, the first memory 21A Is transmitted to the second memory card 20B.

  Hereinafter, the data synchronization method of this embodiment implemented using the data synchronization system 4 is demonstrated with reference to the flowchart shown in FIG. In the following, the first memory card 20A receives data from the connected first external device 10A. In the second memory card 20B, the first buffer is first designated as the read buffer, A data synchronization method when the buffer is designated as an update batter will be described as an example. Note that the processes shown in the flowchart of FIG. 9 can be executed in any order or in parallel as long as the process contents do not contradict each other.

  First, in the first memory card 20A, the data received from the connected external device 10A is stored in the first memory 21A (step S400).

  Next, the first memory card 20A establishes a peer-to-peer connection by wireless communication with the second memory card 20B to establish a wireless communication path (step S401). If the wireless communication path has not been established (step S402: No), the process returns to step S401.

  Next, the first memory card 20A is communicably connected to the second memory card 20B using wireless communication (step S401). If the connection has not been completed (step S402: No), the process returns to step S401.

  When the wireless communication path is established (step S402: Yes), the second memory card 20B transmits the memory information of the data stored in the second memory 21B to the first memory card 20A via the wireless communication path, and The one memory card 20A receives the memory information of the data in the second memory 21B (step S403).

  In the first memory card 20A, it is determined whether or not to update the data stored in the buffer designated as the update buffer with the data stored in the first memory 21A (step S404). For example, the determination can be made using information such as the update time of data included in the memory information held by each of the first memory 21A and the second memory 21B.

  When it is determined to update (step S405: No), in the first memory card 20A, the data stored in the first memory 21A is transmitted to the update buffer of the second memory card 20B (step S406).

  Next, the second memory card 20B receives data from the first memory 21A, and updates the data stored in the second memory 21B based on the received data (step S407).

  When the update is completed (step S408: Yes), the buffer designated as the update buffer and the read buffer is switched in the second memory card 20B (step S409). That is, the first buffer is designated as the update buffer from the public buffer, and the second buffer is designated as the update buffer from the public buffer.

  After the process of step S409 or when not updated in the process of step S405 (step S405: No), this process flow ends.

  As described above, according to the data synchronization system 4 and the method of the present embodiment, the storage unit of the memory card includes the first buffer and the second buffer, and the role of each buffer is updated buffer and public buffer each time update is completed. Since the data stored in one of the buffers can be retained even if the wireless communication between the memory cards is disconnected, the data loss in the memory card can be suppressed.

In the fourth embodiment, the case where the first buffer or the second buffer is designated as the update buffer at regular intervals has been described as an example. However, the present invention is not limited to this. For example, the user writes to the memory card, When it is desired to update the data of the other memory card, the first buffer or the second buffer may be designated as the update buffer based on the operation of the external device connected to the other memory card.
<Modification>

  The preferred embodiments of the present invention have been described above. However, the present invention should not be limited to the above embodiments, and does not depart from the spirit and scope expressed in the claims. Various modifications, additions, and omissions are possible by those skilled in the art.

  For example, although cases have been described with the above embodiments as examples where data synchronization is performed between two memory cards (memory modules), the present invention is not limited to this, and data synchronization can also be performed between a plurality of memory cards.

  Specifically, for example, as shown in FIG. 10, when data received from a PC is written in a memory card connected to the PC, a plurality of other data in a wireless communication possible range (wireless cell) are written. It is possible to realize a system that is communicably connected to a memory card and updates data in each of the other memory cards. At this time, by supplying electric power to the other plurality of memory cards using radio waves, data synchronization can be achieved even when the other plurality of memory cards are not connected to an external device. According to such a system, since the data of the memory card in the wireless cell can be automatically updated, it is easier to duplicate the memory card than in the past.

  As another example, if you want to distribute electronic data at an exhibition hall or seminar, prepare multiple copy-source memory cards that can be written from one external device and multiple copy-destination memory cards. By handing the memory card to participants such as exhibition halls, electronic data can be distributed in real time. In this case, it can be propagated by updating data between the replication destinations. Specifically, in the copy destination memory card, whether or not to update the data stored in the memory in the other memory synchronization target memory card with the data stored in the memory after the data update is performed. If it is determined to be updated, the data stored in its own memory is transmitted to the memory in another data synchronization target memory card, and the data update is propagated. As a result, even if there are not all copy destination memory cards in the wireless communication range of the copy source memory card in a wide exhibition hall, etc., the memory card held by the participant will be transmitted to the remote The memory card can also be updated. At this time, if a distributed copy destination memory card incorporates a mechanism such as “delete recorded data when no data is updated for a certain period of time”, misuse of electronic data can be prevented.

  Further, in each of the above embodiments, the memory card is described as an example of the memory module. However, the present invention is not limited to this, and can be applied to, for example, a small card as another memory card such as a multimedia card. it can.

  Further, in each of the above embodiments, the case where the paired memory cards (memory modules) have the same configuration and function has been described. However, the present invention is not limited to this, and the duplication source memory card and the duplication destination memory card. And may be provided with means as required. For example, when the copy destination memory card is a memory card (parent) to which data can be written from an external device, and the copy source memory card is a memory card (child) from which data cannot be written by an external device, the memory card of the first embodiment is used. For example, the first memory card 20A (replication source memory card) includes the first memory 21A, the first data storage means 22A, the first establishment means 23A, the first determination means 24A, and the first data transmission / reception means 25A. The second memory card 20B (replication destination memory card) may include the second memory 21B, the second establishing unit 23B, and the data updating unit 26B.

  Further, each of the first memory card 20A and the second memory card 20B is provided with each means according to the use, but each means provided in the first memory card 20A and the second memory card 20B is Some of them may be configured together, or one unit may be further divided into a plurality of units.

1 data synchronization system, 10A external device A, 10B external device B, 20A memory card, 20B memory card, 21A first storage means, 21B second storage means, 22A first data writing means, 22B second data writing means, 23A First connection means;
23B second connection means, 24A first determination means, 24B second determination means, 25A first data transmission / reception means, 25B second data transmission / reception means, 26A first data update means, 26B second data update means, 27A first data Reading means, 27B second data reading means.

Claims (9)

A data synchronization system comprising a first memory module having a first memory and a second memory module having a second memory, and synchronizing data stored in the first memory and the second memory,
The first memory module includes:
First data storage means for storing data received from a first external device connected to the first memory module in the first memory;
A first establishment means for establishing a wireless communication path by establishing a wireless communication connection with the second memory module;
Data stored in the second memory with data stored in the first memory based on the received memory information is received through the wireless communication path. First determination means for determining whether to update
If it is determined by the first determination means that the data stored in the second memory is updated with the data stored in the first memory, the data stored in the first memory via the wireless communication path is First data transmission means for transmitting to the second memory module;
The second memory module includes:
A second establishing means for establishing a wireless communication path by establishing a wireless communication connection with the first memory module;
Memory information transmitting means for transmitting memory information of data stored in the second memory to the first memory module via the wireless communication path;
Data updating means for receiving data from the first memory module via the wireless communication path and updating data stored in the second memory based on the received data;
Data reading means for reading data stored in the second memory;
A data synchronization system comprising: The first memory module includes:
Memory information transmitting means for transmitting memory information of data stored in the first memory to the second memory module via the wireless communication path;
Data updating means for receiving data from the second memory module via the wireless communication path, and updating data stored in the first memory based on the received data;
Reading means for reading data stored in the first memory;
First protection means for protecting storage of data in the first memory by the first data storage means;
The second memory module includes:
Second data storage means for storing data received from a second external device connected to the second memory module;
Data stored in the first memory is received as data stored in the second memory based on the received memory information by receiving memory information of the data stored in the first memory via the wireless communication path Second determination means for determining whether or not to update
When it is determined by the second determination means that the data stored in the first memory is updated with the data stored in the second memory, the data stored in the second memory via the wireless communication path is Second data transmitting means for transmitting to the first memory module;
Second protection means for protecting storage of data in the second memory by the second data storage means;
When the first data storage unit receives data from the first external device, the first data storage unit transmits a protection setting notification for causing the second protection unit to execute the protection to the second memory module. After receiving a response notification to the protection setting notification, store data received from the first external device in the first memory;
When the second data storage unit receives data from the second external device, the second data storage unit transmits a protection setting notification for causing the first protection unit to execute the protection to the first memory module. The data synchronization system according to claim 1, wherein after receiving a response notification to the protection setting notification, data received from the second external device is stored in the second memory. The second memory module includes:
Second data storage means for storing data received from a second external device connected to the second memory module;
Second protection means for protecting storage of data in the second memory by the second data storage means;
When the first data storage unit receives data from the first external device, the first data storage unit transmits a protection setting notification for causing the second protection unit to execute the protection to the second memory module. The data synchronization system according to claim 1, wherein after receiving a response notification to the protect setting notification, data received from the first external device is stored in the first memory. The first memory includes a data storage buffer and a data synchronization buffer,
The first data storage means includes means for storing data received from the first external device in the data storage buffer, and means for copying data in the data storage buffer to the data synchronization buffer at a predetermined timing. ,
The first determination means determines whether to update the data stored in the second memory with the data stored in the data synchronization buffer;
When it is determined that the data stored in the second memory is updated with the data stored in the data synchronization buffer by the first determination unit, the first data transmission unit stores the data stored in the data synchronization buffer. The data synchronization system according to claim 1, wherein the data synchronization system is transmitted to the second memory module. The second memory includes a first buffer and a second buffer,
The data update means includes: means for designating one of the first buffer and the second buffer as an update buffer and the other as a read buffer; and the update based on data received from the first memory module Means for updating the data stored in the buffer, and means for switching the buffer designated as the update buffer and the read buffer for each data update,
The first determination means determines whether or not to update the data stored in the buffer designated as the update buffer with the data stored in the first memory,
When it is determined that the first data transmission unit updates the data stored in the buffer designated as the update buffer with the data stored in the first memory by the first determination unit, the first data transmission unit The data synchronization system according to claim 1, wherein data stored in a memory is transmitted to the second memory module.   The data synchronization system according to claim 1, comprising a plurality of the second memory modules. Each of the plurality of second memory modules includes
The memory information of the data stored in the other second memory of the other second memory module is received via the wireless communication path, and the data stored in the second memory of its own based on the received memory information Second determination means for determining whether or not to update data stored in another second memory;
When it is determined by the second determination means that the data stored in the other second memory is updated with the data stored in the second memory of the first, the second memory of the own through the wireless communication path Second data transmission means for transmitting the data stored in the other second memory module,
The second establishing means establishes a wireless communication path by establishing a wireless communication connection with the other second memory module,
The memory information transmitting means transmits the memory information of the data stored in the second memory of its own to the other second memory module via the wireless communication path,
The data update means receives data from the second data transmission means of the other second memory module via the wireless communication path, and stores data in its second memory based on the received data The data synchronization system according to claim 6, wherein the data synchronization system is updated. A first memory for storing data;
Data storage means for storing data received from an external device in the first memory;
Establishing means for establishing a wireless communication path by establishing a wireless communication connection with a data synchronization target memory module;
Memory information of data stored in the second memory of the memory module subject to data synchronization is received via the wireless communication path, and the data stored in the first memory is received based on the received memory information. Determining means for determining whether or not to update data stored in two memories;
Data transmission means for transmitting data stored in the first memory to the data synchronization target memory module via the wireless communication path when the determination means determines that the update is performed;
Data update means for receiving data from the data synchronization target memory module via the wireless communication path and updating the data stored in the first memory based on the received data;
A memory module comprising: A data synchronization method including a first memory module having a first memory and a second memory module having a second memory, and synchronizing data stored in the first memory and the second memory,
The first memory module storing in the first memory data received from a first external device connected to the memory module;
Connecting the first memory module and the second memory module by wireless communication and establishing a wireless communication path;
The second memory module transmits memory information of data stored in the second memory to the first memory module via the wireless communication path;
The first memory module receives the memory information and determines whether to update the data stored in the second memory with the data stored in the first memory based on the received memory information Stages,
If it is determined that the first memory module updates the data stored in the second memory with the data stored in the first memory, the data stored in the first memory via the wireless communication path Transmitting to the second memory module;
Updating the data stored in the second memory based on the data received from the first memory by the second memory module via the wireless communication path;
A data synchronization method comprising:

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