JP2006099648A - Memory control unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently perform write operation to a storage medium after a logical format. <P>SOLUTION: A plurality of access requests generated at the time of logical format request to the storage medium is decided, object area information in the storage medium to be an object of the logical format request is acquired, a simultaneous deletion object area is decided on the basis of the acquired object area information, and when the access request is decided, a block corresponding to the decided area is simultaneously deleted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a logical format process of a memory medium equipped with a non-volatile memory that can be erased in units of blocks composed of a plurality of sectors.

  Conventionally, non-volatile memories that can be erased in units of blocks composed of a plurality of sectors, such as flash memories, are mounted on various information processing apparatuses.

  The flash memory is a non-volatile memory that can be erased in a block unit, for example, a large unit such as 64 Kbytes. This erase unit is an erase block.

  Writing in the flash memory is performed in units of erase blocks or in units smaller than that. When the write data has an erase block size and there is an erased unused erase block, the write data is written to the erase block. Next, an address is assigned to the erase block that has been written, and an erase block in which the original data is stored is assigned to an unused address, and the write operation is terminated.

  When the write data is smaller than the erase block size and there is an erased unused erase block, first, the erase block data including the write target portion is copied to the buffer. Next, the data in the buffer to be written is replaced with the data to be written to create new erase block size data, and the data is written into the erased unused erase block. Finally, an address is assigned to the erase block that has been written, and the erase block in which the original data is stored is assigned to an unused address, and the write operation is terminated.

If there is no erased unused erase block, the erase block is temporarily erased, and the data is erased before writing. When the erase block size is requested to be written, the data is written as it is and the process is terminated. When writing in units smaller than the erase block is requested, the erase block data including the write target portion is copied to the buffer, and the data write target portion is written, as in the case where there is an erased unused erase block. This data is replaced with the write data to create new erase block size data, and the created data is written into the erased erase block, and the process ends. The flash memory technology as described above is described in Patent Document 1 and the like.
JP 2003-099098 A

  However, when there is no erased unused erase block, writing to the flash memory is a time consuming process. Therefore, when writing to a memory medium equipped with flash memory that has been written until all erase blocks are consumed, the writing processing speed is slower than the data transfer speed to the memory medium, and as a result However, there was a problem that the data transfer performance of the data transfer system could not be fully utilized.

  An object of the present invention is to solve the above-described problems, and an object of the present invention is to provide a memory control device that can efficiently perform a write operation to a storage medium after logical formatting.

  In order to achieve the above object, a memory control device according to the present invention is a memory control device capable of collectively erasing a storage area of a storage medium in units of blocks, and a plurality of access requests generated when a logical format request is made to the storage medium. A request determination unit for determining, a region information acquisition unit for acquiring target region information in the storage medium that is a target of the logical format request, and a region information acquisition unit when an access request is determined by the request determination unit And a batch erasing unit that determines a batch erasure target region based on the target region information acquired by the step, and batch erases blocks corresponding to the determined region.

  According to the present invention, it is possible to efficiently perform a write operation to the storage medium after logical formatting.

  Embodiments according to the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the camera system in the first embodiment. The camera system includes an electronic camera, an external storage medium 17 that can be attached to and detached from the electronic camera, a PC communication interface 21, and a personal computer 22 that is communicably connected to the electronic camera via the PC communication interface 21.

  Reference numeral 1 denotes a lens, and reference numeral 2 denotes a CCD unit that outputs light passing through the lens 1 as an electrical signal. An A / D converter 3 converts an analog signal from the CCD unit 2 into a digital signal. An SSG unit 4 supplies a synchronization signal to the CCD unit 2 and the A / D converter 3. Reference numeral 5 denotes a CPU, which implements various controls in the camera system.

  A signal processing accelerator 6 realizes signal processing at high speed. 7 is a battery, and 8 is a DC / DC converter for supplying electric power from the battery 7 to the entire electronic camera. A power controller unit 9 controls the DC / DC converter 8. A microcomputer 10 controls the panel operation, the display device, and the power source. Reference numeral 11 denotes a display device that displays various types of information to the user, and uses a liquid crystal panel or the like. A control panel 12 includes a release switch and a menu button that are directly operated by the user.

  A ROM 13 stores a system program such as an OS. Reference numeral 14 denotes a DRAM which is a main memory of the electronic camera. A flash ROM 15 is used as a built-in storage medium. Reference numeral 16 denotes an SD (Secure Digital) card interface unit, and 17 denotes an external storage medium such as an SD memory card. Reference numeral 18 denotes a DMA controller, and 19 denotes a strobe.

  The operation at the time of photographing with this electronic camera will be described. When the user presses the release switch on the control panel 12, the CPU 5 detects this and starts the shooting sequence. It is assumed that the following operations are all controlled by the CPU 5.

  Now, when the release switch is pressed, the SSG 4 drives the CCD 2. The analog signal output from the CCD 2 is converted into a digital signal by the A / D converter 3. The output of the A / D converter 3 is DMA-transferred to the DRAM 14 by the DMA controller 18. When the DMA transfer for one frame is completed, the CPU 5 starts a signal processing sequence.

  In the signal processing sequence, a signal processing program is read from the flash ROM 15 onto the main memory (DRAM 14), and data on the main memory is transferred to the signal processing accelerator 6 to perform signal processing. However, the signal processing accelerator 6 does not perform all signal processing, but is an arithmetic circuit that helps particularly time-consuming processing performed by the CPU 5, and operates in cooperation with processing software of the CPU 5. When part or all of the signal processing is completed, the image file is recorded on the external storage medium 17 via the card interface 16. If the file format to be recorded at this time requires compression processing, compression is also performed.

  FIG. 2 is a conceptual diagram showing the hierarchical structure of the image file system recorded in the external storage medium 17 shown in FIG.

  In the figure, the highest hierarchy L1 is a user application, which is software that is activated inside the electronic camera. The file is opened with a file name, read / written, and then closed. The hierarchy L2 is a file system API layer and is called from a user application by a function call. The hierarchy L2 manages the drive name and the file system in association with each other. Since the configuration is such that the file system architecture layer (hierarchy L3) is mounted for each drive, a plurality of file system architectures (for example, FAT, HP-FS, NFS, NTFS, etc.) can be mixed. Yes. The file system architecture layer is a part that performs actual file management. The lowest layer L4 is a block device layer.

  The file system architecture layer implements file input / output using services provided by the block device layer. In the block device layer, data is managed in units of sectors such as 512 bytes. The block device layer absorbs differences in input / output control for each device and differences in parameters such as the head and cylinder. This makes it possible to construct a camera system in which a plurality of types of devices are mixed at the same time.

  In the system according to the present embodiment, the services provided by the block device of the external storage medium 17 to the file system are (1) to (3).

  (1) reads data from the sector specified by the logical sector number, (2) writes data to the sector specified by the logical sector number, and (3) specifies the logical sector number This is a sector erase (flash).

  Regarding the service (3), there are some which are not external storage media that provide the service. The present invention is premised on an external storage medium that can provide the service (3), and that the subsequent writing speed is improved by using the service (3). An MMC (Multi Media Card), an SD (Secure Digital) memory card, and the like are examples of an external storage medium having this feature. In the description of this embodiment, an SD memory card is targeted as an external storage medium. The present embodiment will be described using a FAT file system as the file system architecture.

  FIG. 3 shows the software structure of the block device layer of this embodiment. A block device API 301 provides the services (1), (2), and (3). Normally, when a file system architecture layer, which is an upper layer, uses a service, the block device API 301 is directly used. However, the service is used here through the block device service analysis unit 302.

  The services provided by the block device service analysis unit 302 are (1), (2), and (3), and provide the same service as that of the block device API 301 to the file system architecture layer. Therefore, the file system architecture layer can use the service provided by the lower layer in the same manner without any special operation, regardless of whether the lower layer is the block device API or the block device service analysis unit. it can.

  When a file read / write request for the SD memory card is requested to the file system architecture layer, it is divided into a plurality of service requests for the block device layer. Similarly, when a logical format for the SD memory card is required in the file system architecture layer, it is divided into a plurality of service requests for the block device layer. These service requests are requested to the block device service analysis unit 302. The block device service analysis unit 302 includes a logical format determination unit that determines whether the requested service is a service that is requested at the time of logical formatting, and an area information acquisition unit that acquires information on an area that is a target of the logical format in the block device. If the logical format determination means determines that the service is required at the time of logical formatting, the erase target area is determined based on the information acquired by the area information acquisition means, and the erase target area Software that performs the same operation as that of the block device API 301 is performed by erasing the service (3) of the block device API 301.

  Before describing the logical format determination unit and the area information acquisition unit, the FAT file system will be described. FIG. 5 shows the data structure of the storage medium. In the figure, reference numeral 501 denotes an MBR (Master Boot Record), which occupies a data size of 512 bytes from the beginning of the storage medium and has the structure shown in FIG. When the storage medium is a bootable storage medium, the storage medium has a bootstrap loader 601 and a boot program for the storage medium. If it is not bootable, it may not have a bootstrap loader. The bootstrap loader 601 occupies 446 bytes from the top of the MBR 501. Reference numeral 602 denotes a partition table, which stores information on partitions 502 to 50N of the storage medium, and occupies from the 447th byte to the 64th byte and the 510th byte of the MBR501.

  A partition means the division of the storage medium, and one partition is managed by one file system. One storage medium includes at least one partition. The partition table 602 stores the physical start position, end position, logical start position, and total number of sectors of each partition. If there is an exceptionally single partition, it may not have an MBR. In that case, the entire storage medium is regarded as one partition.

  FIG. 7 shows a data structure when one partition is formatted by FAT16, which is an example of the FAT file system. Reference numeral 701 denotes a PBR (Partition Boot Record), which has the structure shown in FIG. In FIG. 8, reference numeral 801 denotes a jump instruction in which a jump instruction to the IPL 803 is stored. Reference numeral 802 denotes a BPB (BIOS Parameter Block) in which information on the file system, in particular, information specific to this partition is recorded. FIG. 11 shows parameters included in the BPB. Reference numeral 803 denotes an IPL (Initial Program Loader) in which a startup program for this partition is stored.

  Reference numerals 702 and 703 in FIG. 7 denote FAT (File Allocation Table), which stores file position information stored in the user data area 705. The FAT file system acquires the position information of the file stored in the partition by using the FATs 702 and 703. Therefore, even if a file is stored in the user data area, it cannot be recognized as a file unless the location information of the file is stored in the FATs 702 and 703. A directory entry 704 stores management information of files stored in the root directory. Reference numeral 705 denotes a user data area in which the file body is stored.

  The area information acquisition unit included in the block device service analysis unit 301 will be described. The area information acquisition unit operates according to the procedure shown in the flowchart of FIG. 13, and recognizes the user area of the partition accessed by the requested service. First, in 1301, it is determined whether the storage medium partition information is held. If it is determined that the storage medium is not held, the partition table in the MBR (512 bytes from the top) of the storage medium is analyzed in 1302 to obtain partition information included in the storage medium. From this information, the partition accessed by the requested service is identified at 1303. Next, it is determined whether the BPB parameter information of the partition specified in 1304 is retained. If not, the BPB of the partition is analyzed at 1305 to obtain parameter information included in the BPB. From this information, the FAT, directory entry, and user data area are specified in 1306. The start address and end address of the user data area can be obtained by the calculation formula shown in FIG. In this way, the area information acquisition unit specifies the user data area of the partition accessed by the requested service.

  The logical format determination unit included in the block device service analysis unit 302 will be described. The logical format determination means requires user data area used capacity information indicating the used capacity of the user data area. The user data area used capacity information is used to determine whether the FAT is in the all-deleted state. FIG. 14 is a flowchart showing an operation when the logical format determination unit determines whether the requested service is a service requested at the time of logical formatting.

  First, in step S1401, target area information of the service requested by the area information acquisition unit is acquired. In S1402, it is determined whether the user data area usage capacity information is held. If not, the FAT is analyzed in S1406, and the user data area usage capacity information is acquired and held. The user data area usage capacity information is acquired at the time of logical formatting, physical formatting, power-on, or storage medium change. Next, based on the target area information, it is determined whether the service requested in S1402 is an access to the BPB. If the service is an access to the BPB, whether the BPB contents are written by executing the service in S1407. Investigate. Based on this result, it is determined in S1408 whether the written content is a volume name. If it is other than the volume name, it is determined in S1409 whether the FAT position, size, and number are changed. If there is a change, the user data area usage capacity information is discarded in S1415, and this determination operation determines that the requested service is a service requested at the time of formatting and ends. If it is determined that the service for discarding the user data area used capacity information is a service required at the time of formatting, if the FAT position, size, or number is changed, the validity of the FAT information is lost. This is because the user data area use capacity is also invalid.

  If the determination operation is not completed in the steps described above, it is determined whether the service requested in S1404 is an access to the FAT. If it is determined that the access is to the FAT, it is determined whether or not the FAT has been changed by executing the service requested in S1410. If it is determined that there is a change, the change is retained from the FAT change in S1411. The user data area used capacity information is changed. In step 1412, it is determined from the user data area used capacity information whether the file is completely deleted (used capacity is 0). If it is determined in S1412 that the data is completely deleted, the user data area usage capacity information is discarded in S1415, and this determination operation determines that the requested service is a service requested at the time of formatting and ends.

  In the steps after S1404, if this determination operation is not terminated, it is determined whether the service requested in S1405 is an access to the MBR. If it is determined that the access is to the MBR, it is determined in S1413 whether there is a change in the partition table in the MBR by executing the service. If it is determined that there is a change to the partition table, the user data area usage capacity information is discarded in S1414. Regardless of which determination is made in S1413, this determination operation determines that the requested service is a normal service request and ends. With the method described above, the logical format determination means determines the requested service.

  The service providing operation for the upper layer of the block device service analysis unit 302 will be described below. FIG. 4 is a flowchart showing an operation when the block device service analysis unit 302 provides a service to an upper file system architecture layer. In this operation, a logical format flag indicating whether the logical format is being executed is used. The logical format flag is set when a service requested at the time of logical formatting is detected by the logical format determination means when a series of service requests in the logical format is performed, and it is determined that the series of service requests has ended. In other words, it is reset when an access request to the user data area is made. In the logical format determination means, a series of services required at the time of logical formatting, for example, a service determined to be a service required at the time of logical formatting, such as a parameter change excluding a BPB volume name or a total deletion of FAT. There are multiple types of. Therefore, there is a possibility that the erase operation is executed a plurality of times with a single logical format request. Therefore, once the logical format determination means recognizes a service required at the time of logical formatting and performs an erase operation, the logical format flag is used to prevent the erase operation from being performed until the logical format is completed. .

  When the block device service analysis unit 302 is requested for service, first, the logical format flag is referred to in S401. In step S402, the state of the logical format flag is determined. If the logical format flag is not set, the logical format determination unit determines the type of service requested. The circle A in S410 is connected to the circle A in FIG. If it is determined by the logical format determination means that the service is required at the time of logical formatting, the process proceeds to circle B in S411, the user information area is determined by the area information acquisition means in S405, and the user data is determined in 406. An erase operation is performed on the area using the service (3) of the lower block device API. Subsequently, in S407, the logical format flag is set.

  If it is determined in S402 that the logical format flag is set, an area to be accessed by the requested service is determined in S403, and it is determined in S404 whether the access is to the user data area. If it is determined that the access is to the user data area, it is determined that a series of service requests in the logical format has been completed, and the logical format flag is reset in S408.

  Regardless of which determination is made in S404, regardless of which determination is made by the logical format determination means, the service of the block device API 301 corresponding to the service requested in S408 is finally executed, and the request is made. Complete.

  By performing the erase operation automatically on the user data area in the partition subject to the logical format at the time of logical formatting by the above method, the writing operation performance to the user data area after the logical formatting is improved. . Further, by automatically recognizing the logical format and executing the erase operation in the block device layer, the existing file system software can be used as it is, and the change can be facilitated.

  In the description of the present embodiment, the FAT file system is taken as an example of the file system architecture. However, for any file system architecture, the block device service analysis unit 302 performs the logical format determination unit and the area information. Needless to say, the present invention can be applied to the case where acquisition means is provided.

  Furthermore, in the description of the present embodiment, an SD memory card is taken as an example of an external storage medium. However, the feature that an erase service can be provided by any storage medium, and the erase service is used. Thus, it goes without saying that the present invention can be applied to the case where the subsequent write operation performance is improved.

(Second Embodiment)
FIG. 9 is a block diagram showing an example of a memory medium equipped with an erasing mechanism at the time of formatting according to the second embodiment of the present invention, and a system in which the memory medium can be attached and detached, such as a digital camera. In FIG. 1, reference numeral 920 denotes a memory medium, and reference numeral 910 denotes a system to which the memory medium 920 can be attached and detached.

  In the figure, reference numeral 911 denotes a CPU that controls the operation of the system 910. Reference numeral 912 denotes a ROM that stores a program executed by the CPU 911 and data that is necessary when the program is executed and does not change dynamically. A RAM 913 is used as a temporary storage area when the CPU 911 executes a program stored in the ROM 912. Reference numeral 914 denotes a memory media controller, which is controlled by the CPU 911 and which issues a control command for controlling the memory media 920, a means for transferring data stored in the memory media 920 to the RAM 913, and a RAM 913 And a means for transferring the received data to the memory medium 920. A user interface 915 receives a request from a user who uses the system 910 and notifies the CPU 911 of the user request.

  921 is a controller, means for receiving a control instruction transmitted from the system 910, control instruction decoding means for decoding the control instruction, means for executing the decoded control instruction, and a partition accessed by the control instruction It is characterized by having area information acquisition means for acquiring the area information, and the memory medium 920 is controlled based on these means. Here, the control command decoding means has the same ability as the logical format determination means included in the block device service analysis unit in the first embodiment, and the area information acquisition means has the same ability as the area information acquisition means.

  Reference numeral 922 denotes a ROM which stores a program required when the CPU 921 executes the decoded control instruction and data required when the program is executed. A RAM 923 is used as a temporary storage area for programs and data executed by the CPU 921. A flash memory 924 stores data transferred from the system 910.

  Hereinafter, operations of the system 910 and the memory medium 920 when an operation request is made to the system 910 by the user of the system 910 operating the user interface 915 will be described.

  When the user of the system 910 operates the user interface 915, the operation request is notified to the CPU 911. Upon receiving the operation request, the CPU 911 expands a program that realizes the operation request and data necessary for executing the program from the ROM 912 to the RAM 913 and executes the program. If there is any change in the system 910 after the execution of the program and it is necessary to notify the user of this change, the CPU 911 controls the user interface 915 to notify the change.

  The operation of data transfer processing for transferring data from the system 910 to the memory medium 920 or from the memory medium 920 to the system 910 will be described below.

  When a request for data transfer processing is given from the user of the system 910 to the user interface 915, the user interface 915 notifies the CPU 911 of the request for data transfer processing. When the CPU 911 receives the request for the data transfer process, the CPU 911 requests the memory media controller 914 to issue a control command for the memory medium 920 for the data transfer process. Upon receiving the request, the memory media controller 914 creates a control command and transmits the control command to the memory media 920.

  The control command transmitted to the memory medium 920 is received by the CPU 921, expanded in the RAM 923, and decoded. If the result of decoding is a data transfer from the memory medium 920 to the system 910 according to the procedure of decoding the control command by the CPU 921 described later, the data at the address specified in the control command is transmitted from the flash memory 924. Conversely, if the result of decryption is data transfer from the system 910 to the memory media 920, the data received after the control instruction is written to the address specified in the control instruction of the flash memory 924. In any case, when the process is completed, the CPU 921 notifies the memory media controller 914 of the completion of the control command.

  Upon receiving the control command completion notification, the memory media controller 914 sends a request completion notification to the CPU 911. Upon receiving the request completion notification, the CPU 911 sends a request completion notification to the user interface 915. The user interface 915 indicates completion of request processing to the user.

  Hereinafter, an operation when the system 910 logically formats the memory medium 920 will be described. Performing a logical format means performing at least one data transfer process. When the user interface 915 receives a logical format request from a user of the system 910, the user interface 915 notifies the CPU 911 of the logical format request. The CPU 911 receives the notification of the logical format request and divides it into at least one data transfer request. The CPU 911 notifies the data transfer request to the memory media controller 914 in order. The data transfer request is processed by the memory media controller 914 in the same procedure until the above-described data transfer request from the system 910 to the memory medium 920 and the CPU 921 expands the control command to the RAM 923. The subsequent operation is determined based on the result of decoding by the CPU 921.

  FIG. 10 is a flowchart showing an example of a procedure for decoding a control command by the CPU 921. Hereinafter, a procedure for decoding a control command by the CPU 921 will be described.

  When the CPU 921 starts decoding the control command, first, in S1001, an erase flag indicating whether the flash memory 924 is being erased is referred to. If the erase flag is set, the control instruction type is determined by the control instruction decoding means in S1002. If the erase flag is not set, the control command is stored in the RAM 923 in S1008 and the control command processing is completed.

  If it is determined in S1002 that it is a control command issued during logical formatting in S1003, the erase flag is set in S1004, and the erase command for the flash memory 924 stored in the ROM 923 is stored in the RAM 922 in S1005. The data is expanded and the flash memory 924 is erased for the user data area determined based on the partition information acquired by the area information acquisition means. On the other hand, if it is not determined in S1003 that the control command is issued at the time of logical formatting, the control command is executed in S1009 and the control command processing is completed.

  When the erasure to the flash memory 914 is completed in S1005, the erasure flag is reset in S1006, and it is determined in S1007 whether there is a control command stored in the RAM 923 during the erasure. If the control command exists, the control command is executed in S1010. If S1007 and S1010 are repeated and it is determined in S1007 that the control command does not exist, the control command processing is completed. In either case of executing S1008 and S1009, or determining that there is no control command in the RAM 923 in S1007, the CPU 921 sends a control command completion notification to the system 910 when the control command processing is completed. Upon receiving this completion notification, the memory media controller 914 sends a request completion notification to the CPU 911.

  The CPU 911 does not send a request completion notification to the user interface 915 until receiving a request processing completion notification for each of at least one data transfer request obtained by dividing the logical format request. When the request completion notification for all the divided data transfer requests is received, the request completion notification is sent to the user interface 915 for the first time, and the user interface 915 that has received this request completion notification notifies the user of the request completion.

  When logical formatting is performed using the method described above, a control command issued during logical formatting is detected in the memory medium, and the erase operation is performed on the user data area in the partition subject to logical formatting. The write operation performance for the later user data area is improved. In addition, the present invention can be realized without making any special changes to the system by implementing a function for automatically detecting and erasing the control command during formatting in the memory medium. .

  Here, it is needless to say that the logical format request given to the CPU 911 includes not only the user interface 915 but also the case where the CPU 911 automatically performs it or the case where it occurs during execution of a certain request. Furthermore, when the system 910 issues a control command to the memory medium 920, if the specification is such that the next control command is not issued until a completion notification is received, the memory medium need not have the erasure flag. Needless to say.

It is a block diagram which shows an example of the image processing system which can adapt the memory control apparatus which shows 1st Embodiment of this invention. It is a conceptual diagram which shows the hierarchical structure of the image file system recorded on flash ROM shown in FIG. 1, and an external storage medium. FIG. 3 is a block diagram showing a software structure in the block device layer shown in FIG. 2, which is a feature of the first embodiment of the present invention. It is a flowchart figure which shows an example of the service processing procedure of the block device service analysis part shown in FIG. It is a block diagram which shows the internal data structure in a storage medium. It is a block diagram which shows the internal data structure of MBR in FIG. FIG. 6 is a block diagram showing an internal data structure when the partition in FIG. 5 is formatted with the FAT file system. It is a block diagram which shows the internal data structure of PBR in FIG. It is a block diagram which shows an example of the memory medium and system with the memory control mechanism which show 2nd Embodiment of this invention. FIG. 10 is a flowchart showing an example of a control instruction processing procedure of the memory medium in FIG. 9. It is a table | surface which shows the parameter of the partition contained in BPB in FIG. 12 is a calculation formula for calculating the start address and the end address of the user data area in FIG. 7 from the parameters in FIG. It is a flowchart figure which shows the determination method of the area | region information acquisition means in 1st Embodiment of this invention. It is a flowchart figure which shows the determination method of the logical format determination means in 1st Embodiment of this invention.

Explanation of symbols

5 CPU
16 Card interface 17 External storage medium

Claims (6)

A memory control device capable of collectively erasing a storage area of a storage medium in units of blocks,
Request determination means for determining a plurality of access requests generated at the time of a logical format request to the storage medium;
Area information acquisition means for acquiring target area information in the storage medium that is the target of the logical format request;
A batch erase unit that determines a batch erase target area based on the target area information acquired by the area information acquisition unit and batch erases blocks corresponding to the determined area when the request determination unit determines an access request; A memory control device comprising: A setting means for setting a logical format flag when the logical format is executed;
2. The memory control device according to claim 1, wherein when the logical format flag is not set, the request determination unit determines the plurality of access requests. Setting means for setting a logical format flag when a logical format is executed;
An area determination means for determining whether an access request to the user data area is made when the logical format flag is set;
The memory control device according to claim 1, further comprising:   4. The memory control device according to claim 3, wherein when the area determination unit determines that an access request to the user data area is made, the setting unit resets the logical format flag.   The memory control device according to claim 1, wherein the block includes at least one sector.   The memory control device according to claim 1, wherein the storage medium is an SD memory card.

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