JP2006065505A - Memory card and reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To speedily extract data from a memory card and reproduce it, even in an inexpensive reproducing apparatus having low throughput and small memory capacity. <P>SOLUTION: The inside of a semiconductor memory 42 is provided with a dedicated data region 31 for storing data of a dedicated file system different from an FAT file system, and a dedicated file system managing region 32 indicating an access method to the dedicated data region 31. Data of each file is stored in sectors continuing according to a reproduction order of the data using the head of each sector as the starting position in the dedicated data region 31. File information required for an access to each file in the dedicated data region 31 is stored in continuous sectors using the head of each sector as the starting position in the dedicated file system managing region 32. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a memory card that can reduce the processing of the playback device and the memory capacity, and a dedicated playback device that plays back data from the memory card.

  As a memory card, which is a card-type external storage device using a semiconductor memory, a Memory Stick (trademark) or the like is widely used. In such a memory card, a FAT (File Allocation Tables) file system is generally adopted as a file system for managing data (see, for example, Patent Document 1). The purpose of this is to make it possible to easily handle data stored in a memory card in a general system equipped with an OS such as Windows (registered trademark).

  FIG. 10 shows a physical format of a flash memory of a conventional memory card adopting a FAT file system. The flash memory area is divided into a system area and a data area. In the system area, a unique information area (Boot Block) 81 storing information unique to each flash memory is provided.

  The data area includes a boot area 82, a FAT 83, a root directory 84, and a folder area 85 below the area, and an area 86 for storing data (directory and file data) in each folder.

  The folder area 85 stores start cluster and size information for each file. The FAT 83 stores information on the cluster number of each cluster following the start cluster for each file.

  FIG. 11 is a flowchart showing a process of reproducing data by the FAT file system from such a conventional format memory card. First, by reading the boot area 82, the FAT 83, and the root directory 84 in the data area, the memory stick is recognized as a memory stick formatted by the FAT file system (step S31).

  Subsequently, the determination of whether or not the information about the folder to be read (here, the folder “A”) has been read is repeated while reading the information about the folder from the root directory 84 one by one (steps S32 and S33). ).

  When the answer is yes, the storage location of the information about the folder “A” in the folder area 85 is accessed, and a determination is made as to whether or not the information about the file to be read (here, the file “A”) is read. It repeats while reading the information about each file in the folder “A” one by one (steps S34 to S36).

  If the answer is yes, information on the start cluster and size for the file “A” is acquired (step S37), and data for one cluster is read based on the acquired cluster information (step S38). Subsequently, based on the acquired size information, it is determined whether or not reading of the file “A” is completed (step S39).

  If no, the information of the next cluster number for the file “A” is obtained from the FAT 83 one by one (step S40), and the process of step S38 and the determination of step S39 are repeated. And if it becomes YES, a process will be complete | finished.

In addition, the flash memory in the memory card can be accessed by directly specifying the address of the physical block in the flash memory, or by specifying the logical block address and converting the address to the physical block address. And how to access it. Conventionally, when the latter method is adopted, as shown in FIG. 12, a logical-physical conversion correspondence table showing a correspondence relationship between each logical block and each physical block of the flash memory is provided, and the correspondence table is referred to. Thus, the address of the logical block is converted into the address of the physical block (see, for example, Patent Document 2).
JP 2002-373314 A (paragraph number 0020, FIG. 4) JP 2001-325128 A (paragraph numbers 0064 to 0070, FIGS. 11 to 13)

  However, in the conventional memory card that employs the FAT file system, as shown in FIG. 11, when data is reproduced, the file entry is searched (corresponding to steps S32 and S33 in FIG. 11) → the file data is saved. A procedure for detecting the position (corresponding to steps S34 to S36 in FIG. 11) → determining the connection of data in the file while referring to the FAT and extracting the data (corresponding to steps S37 to S40 in FIG. 11) is required. Become.

  For this reason, each time a file in a different folder is reproduced, the file entry must be searched, and it takes time to detect the storage location of the file data. Furthermore, since it is necessary to determine the connection of data in the file with reference to the FAT even after detecting the storage position of the file data, it takes time to extract the data. As a result, it takes time to reproduce the data.

  When data is to be played back by an inexpensive playback device that does not have a high processing capability, such file entry search processing and data extraction processing increase the load.

  Here, if the entry information is stored in the cache memory on the reproducing apparatus side, the storage position of the file data can be quickly detected. However, in order to do so, it is necessary to increase the memory capacity of the playback device, which is an obstacle to creating the playback device at low cost.

  Further, since the logical-physical conversion correspondence table as shown in FIG. 12 has a data size that is approximately proportional to the number of physical blocks of the flash memory, in the case of a memory card having a large capacity (the number of physical blocks is large). The data size becomes considerably large. For this reason, if this logical-physical conversion correspondence table is provided on the playback device side, the memory capacity of the playback device must also be increased, which is an obstacle to creating the playback device at low cost.

  An object of the present invention is to solve the above-described problems, and to make it possible to quickly retrieve and reproduce data from a memory card even in an inexpensive reproducing apparatus having a low processing capacity and a small memory capacity. Is.

  In order to solve this problem, a memory card according to the present invention shows a dedicated data area for storing data of a dedicated file system different from the FAT file system in a semiconductor memory, and a method for accessing the dedicated data area. A dedicated file system management area. In this dedicated data area, the data of each file is stored in successive sectors according to the data reproduction order, starting from the start of the sector. In the area, file information necessary for accessing each file in the dedicated data area is stored in successive sectors starting from the start of the sector.

  This memory card has a dedicated data area in which data of a dedicated file system different from the FAT file system is stored in a semiconductor memory, and a dedicated file system management area indicating an access method to the dedicated data area. .

  Therefore, data can be reproduced from the dedicated data area by a dedicated file system having a procedure of “access to the dedicated file system management area” → “access to the dedicated data area by the access method indicated by the management area”.

  In the dedicated data area, the data of each file is stored in successive sectors according to the data reproduction order, starting from the start of each sector. In other words, the data of each file is linearly arranged in units of sectors.

  Similarly, in the dedicated file system management area, file information necessary for accessing each file in the dedicated data area is linearly arranged in units of sectors.

  Therefore, a playback device that plays back data from this memory card can detect the storage location of the file data to be played and determine the connection of the data in the file by simply accessing the dedicated file system management area. Can do. That is, the storage position of the file data is detected and the connection of the data in the file is determined without searching for the file entry or referring to the FAT as in the processing by the conventional FAT file system (FIG. 11). Can do.

  As a result, even in an inexpensive reproducing apparatus having a low processing capacity and a small memory capacity, the data stored in the memory card can be quickly extracted and reproduced.

  In this memory card, as an example, in the dedicated file system management area, in addition to file information, commands for each file in the dedicated data area are stored in successive sectors starting from the start of the sector, that is, The file information is preferably stored in a command interpreter format.

  By storing the file information in the command interpreter format in this way, it becomes possible to further reduce the processing load on the playback device.

  Next, the playback apparatus according to the present invention includes a dedicated data area for storing data of a dedicated file system different from the FAT file system in the semiconductor memory, and a dedicated file system management area indicating a method for accessing the dedicated data area. In this dedicated data area, the data of each file is stored in consecutive sectors according to the data reproduction order starting from the start of the sector, and this dedicated file system management area has this dedicated data area. File information necessary for accessing each file in the data area is stored in this dedicated file system management area in a playback device that reproduces data from a memory card stored in successive sectors starting from the beginning of each sector. The first process to access and this dedicated file system management area Based on the file information of the inner, characterized by comprising a processing means for performing a second process of reading sequential data from the private data area.

  This reproducing device reproduces data from the memory card according to the present invention by a dedicated file system, and even if the processing capacity is low and the memory capacity is small, the data is quickly taken out from the memory card and reproduced. can do.

  In this playback apparatus, as an example, a table storing the addresses of physical blocks in the semiconductor memory of the memory card that are set to be inaccessible, and data in the physical blocks in the semiconductor memory. The address numbers arranged in ascending order from the smallest physical block address number that can store the memory block are determined as the logical block address, and when accessing the semiconductor memory of the memory card, the specified logical address is selected from the addresses in this table. Processing means for converting to the address of the physical block by adding the number of addresses having an address number smaller than the address of the physical block corresponding to the address of the block to the address of the physical block corresponding to the designated logical block; It is suitable to further comprise A.

  In a semiconductor memory, it is generally permitted to set a predetermined number of physical blocks as defect areas that cannot be accessed. Since this inaccessible physical block is a small number in the entire physical block, the table storing the address of the inaccessible physical block indicates the correspondence between each logical block and each physical block. The data size is much smaller than in the table (FIG. 12).

  Then, the address numbers arranged in ascending order from the smallest physical block address number that can store data in the semiconductor memory are determined as the logical block address, and when accessing the semiconductor memory, the address in this table is specified. The address of the physical block corresponding to the address of the specified logical block is added to the address of the physical block corresponding to the specified logical block, and the address is converted to the address of the physical block. Can do.

  By performing conversion to physical block addresses using the inaccessible physical block table in this manner, even if the memory capacity is small, the logical block address can be specified and the memory card according to the present invention can be used. Data can be quickly retrieved and played back.

  According to the memory card of the present invention, it is possible to quickly retrieve and reproduce data even in an inexpensive reproducing apparatus having a low processing capacity and a small memory capacity.

  According to the reproducing apparatus of the present invention, it is possible to quickly retrieve and reproduce data from the memory card according to the present invention even when the processing capability is low and the memory capacity is small.

  In addition, even if the memory capacity is small, it is possible to obtain the effect that the address of the logical block can be designated and the data can be quickly taken out and reproduced from the memory card according to the present invention.

  Hereinafter, the present invention will be specifically described with reference to the drawings. In the following, an example will be described in which the present invention is applied to a memory stick storing a language hearing test problem (voice data that pronounces a word or the like) and a dedicated player for reproducing the test problem from the memory stick.

  FIG. 1 is a block diagram showing a circuit configuration example of a memory stick to which the present invention is applied. The memory stick 1 includes a control block 41 and a flash memory 42 configured as a one-chip IC. The bidirectional serial interface between the Memory Stick 1 and an external system consists of 10 lines. The four main lines are a clock line SCK for transmitting a clock during data transmission, a status line SBS for transmitting status, a data line DIO for transmitting data, and an interrupt line INT. In addition, two GND lines and two VCC lines are provided as power supply lines. Two lines Reserv are undefined lines.

  The clock line SCK is a line for transmitting a clock synchronized with data. The status line SBS is a line for transmitting a signal representing the status of the memory card 40. The data line DIO is a line for inputting and outputting commands and encrypted audio data. The interrupt line INT is a line for transmitting an interrupt signal for requesting an interrupt from the memory card 40 to the CPU 2 of the recorder 1.

  The control block 41 has a serial / parallel conversion / parallel / serial conversion / interface block (abbreviated as S / P, P / S, IF block) 43 and a control block connected to the external system connected via the above-described plurality of lines. 41 is an interface. The S / P, P / S, and IF block 43 converts serial data received from an external system into parallel data, fetches it into the control block 41, converts parallel data from the control block 41 into serial data, and converts the external data into external data. Send to system.

  In the format transmitted via the data line DIO, a command is transmitted first, and then data is transmitted. The S / P, P / S, and IF block 43 stores a command in the command register 44 and stores data in the page buffer 45 and the write register 46. An error correction encoding circuit 47 is provided in association with the write register 46. For the data temporarily stored in the page buffer 45, the error correction encoding circuit 47 generates a redundant code of the error correction code.

  Output data of the command register 44, page buffer 45, write register 46, and error correction encoding circuit 47 is supplied to a flash memory interface and a sequencer (memory I / F, abbreviated as sequencer) 51. The memory IF / sequencer 51 is an interface between the control block 41 and the flash memory 42 and controls data exchange between the two. Data is written to the flash memory 42 via the memory IF and the sequencer 51.

  Data read from the flash memory 42 is supplied to the page buffer 45, the read register 48, and the error correction circuit 49 via the memory IF and the sequencer 51. Data stored in the page buffer 45 is error-corrected by the error correction circuit 49. The error-corrected output of the page buffer 45 and the output of the read register 48 are supplied to the S / P, P / S, and IF block 43 and supplied to an external system via the above-described bidirectional serial interface.

  The configuration ROM 50 stores version information of the memory stick 1 and various attribute information. The switch 60 is a switch for preventing accidental erasure that can be operated by a user as required. When the switch 60 is in an erasure-prohibited connection state, a command for erasing the flash memory 42 is an external system. Erasing is prohibited even if sent from. The oscillator 61 generates a clock that is a timing reference for processing of the memory card 40.

  FIG. 2 is a block diagram showing a circuit configuration example of a player to which the present invention is applied. This player 11 is a dedicated device for playing back test questions by detachably attaching the memory stick 1 of FIG. The player 11 is provided with an interface block 12, an operation unit 14, a controller 15 including a microcomputer, a decoder 16, a D / A converter 17, and an earphone terminal 18. The interface block 12 is an interface with the memory stick 1 connected via a plurality of lines of the bidirectional serial interface described above. The interface 12, the operation unit 14, the controller 15, and the decoder 17 are connected to the bus 13.

  The operation unit 14 is provided on the housing surface of the player 11 and includes a playback button for playing back the test questions one by one from the memory stick 1. Based on the operation of the playback button, the controller 15 sends a command to the memory stick 1 to execute processing as shown in FIG.

  Data input from the memory stick 1 to the interface block 12 is sent from the interface block 12 to the decoder 16 via the bus 13. The decoder 16 performs a process of decoding audio data compressed by a compression method such as ATRAC3 (Adaptive TRansform Acoustic Coding 3). The audio data decoded by the decoder 16 is converted to an analog audio signal by the D / A converter 17 and output from the earphone terminal 18.

  FIG. 3 shows a physical format of the flash memory 42 of the memory stick 1. The area of the flash memory 42 is divided into a system area 20 and a data area 30. The system area 20 is provided with a unique information area (Boot Block) 21 storing information unique to each flash memory 42 and a dedicated file area 22. The dedicated file area 22 is an area different from the Boot Block 21 and cannot be accessed by the FAT file system.

  In the data area 30, a dedicated data area 31 and a dedicated file system management area 32 are provided. FIG. 4 is a diagram showing details of the dedicated data area 31 and the dedicated file system management area 32. In the dedicated data area 31, N questions (voice data) are stored as data of files 31 (1) to 31 (N) after being compressed by a compression method such as ATRAC3. The data of each of the files 31 (1) to 31 (N) is stored in physically continuous areas (sector numbers are continuous) according to the data reproduction order. The size of one sector is 512 bytes.

  The dedicated file system management area 32 includes a header information area 32a, a file information area 32b, and a file extension information area 32c. In the header information area 32a, an offset to the information in the file information area 32b and the file extension information 32c, version information, and the like are stored.

  The file information area 32b stores information necessary for file access, such as a data start sector number, file size, and file name, for each individual file 31 (1) to 31 (N) in the dedicated data area 31. Has been.

  In the file extension information area 32c, for each individual file 31 (1) to 31 (N) in the dedicated data area 31, a command for that file (information of operations performed by the player 11 in FIG. 2 on that file). Is stored.

  In the dedicated data area 31 and the dedicated file system management area 32, it is possible to create a file having a file size of zero and storing only commands for the file in the file extension information area 32c. Data is not reproduced, and only the command stored in the file extension information area 32c is executed.

  FIG. 5 is a diagram showing in more detail how data of files 31 (1) to 31 (N) are stored in the dedicated data area 31. The data of the file 31 (1) is a series of sectors S (m), S (m + 1), S (m + 2),... S (m + i) according to the data reproduction order, starting from the head of the sector S (m). Stored in i sectors.

  Since the data size of the file 31 (1) has a fraction with respect to a multiple of the sector size (512 bytes), the last sector S (m + i) has an unstored portion of data (in the figure, data The storage part is drawn with diagonal lines and the non-storage part is drawn with a white background). However, with this unstored portion remaining, the data of the next file 31 (2) starts from the head of the sector S (m + i + 1) following the sector S (m + i), and starts from the sector S ( m + i + 1), S (m + i + 2),... S (m + i + j).

  Then, although there is an unstored portion of data in the last S (m + i + j) of the sector, the data of the next file 31 (3) continues to the sector S (m + i + j) while leaving this unstored portion. Starting from the beginning of S (m + i + j + 1), the data is stored in k consecutive sectors S (m + i + j + 1), S (m + i + j + 2),... S (m + i + j + k) according to the data reproduction order.

  In this way, the data of each of the files 31 (1) to 31 (N) is stored in successive sectors according to the data reproduction order, with the start of the sector as the start position. In other words, the data of each of the files 31 (1) to 31 (N) is linearly arranged in units of sectors (in consideration of sector boundaries).

  Although illustration is omitted, the file information and commands for each file in the dedicated data area 31 are also transferred to the file information area 32b and the file extension information area 32c in the dedicated file system management area 32 of FIG. , Each sector is stored in consecutive sectors with the start position as the start position. That is, these file information and commands are also linearly arranged in units of sectors.

  The dedicated file area 22 in the system area 20 of FIG. 3 is an area in which information on the sector number of the dedicated file system management area 32 is stored as information indicating an access method to the dedicated file system management area 32. Note that the memory in the controller 15 of the player 11 in FIG. 2 stores in advance information on the logical address of the dedicated file area 22 (logical address as described later with reference to FIG. 6).

  In the data area 30, a boot area 33, a FAT 34, a root directory 35, and a folder 36 thereunder (only one folder "A" in this case) are provided as management areas for the FAT file system. The dedicated data area 31 and the dedicated file system management area 32 described above are allocated as areas of the respective files in the folder “A” (here, five files “A” to “E”).

  The folder area 36 stores information about the start clusters and sizes of the files “A” to “E”. These start clusters are dedicated data areas as shown by arrows in the figure. Regardless of the data arrangement of the files 31 (1) to 31 (N) in the file 31, the cluster is in an appropriate position in the dedicated data area 31 or the dedicated file system management area 32. The size of one cluster is 16K bytes.

  The FAT 34 stores information on the cluster number of each cluster following the start cluster for each of the files “A” to “E”. These clusters are also stored in the file 31 (1) in the dedicated data area 31. ) To 31 (N) regardless of the data arrangement, the cluster is at an appropriate position in the dedicated data area 31 or the dedicated file system management area 32.

  Therefore, the data read based on the information in the management area for the FAT file system is data in which the arrangement of the data in the dedicated data area 31 (original test question voice data) is changed.

  The controller 15 of the player 11 in FIG. 2 designates the address of the logical block, converts the designated logical block address into the physical block address of the flash memory 42 of the memory stick 1, and converts the physical block address information into the memory stick. 1 control block 41 is sent.

  FIG. 6 shows a table stored in the memory in the controller 15 for converting the logical block address into the physical block address of the flash memory 42.

  In a semiconductor memory, it is generally permitted to set a predetermined number of physical blocks as defect areas that cannot be accessed. The flash memory 42 of the memory stick 1 has a capacity of 16 Mbytes and the number of physical blocks is 1024. However, there are 990 physical blocks that can store data, and 32 physical blocks are physical blocks that cannot be accessed. (The remaining two physical blocks are management physical blocks).

  A non-access address table 70 storing addresses of 32 inaccessible physical blocks in the flash memory 42 is stored in the memory in the controller 15. One address is represented by 4 bytes. Therefore, the data size of the non-access address table 70 is 4 × 32 = 128 bytes.

  FIG. 7 shows the data size in the case where a logical-physical conversion correspondence table showing the correspondence between each logical block and each physical block capable of storing data is provided for the flash memory 42. Since there are 990 physical blocks in which data can be stored, if the logical-physical conversion correspondence table 71 in which 990 logical blocks corresponding to these physical blocks are each represented by 4 bytes is provided, the data size is 4 × 990≈ It becomes 4K bytes.

  Thus, since there are a small number of inaccessible physical blocks in the entire physical block, the non-access address table 70 in the memory in the controller 15 is a logical − that indicates the correspondence between each logical block and each physical block. The data size is much smaller than the physical conversion correspondence table.

The controller 15 determines the addresses of logical blocks corresponding to the addresses of 990 physical blocks that can store data in the flash memory 42 according to the following rules.
[Rule]: Of the 990 physical blocks capable of storing data, the address number of the logical block corresponding to the address with the smallest address number is (1 + A), and the logical block corresponding to the address with the second smallest address number The address number of the physical block is (2 + A),... And the address number of the logical block corresponding to the address with the smallest address number is (990 + A). 1 + A) to (990 + A) and the address number are determined as logical block addresses.

  A is a predetermined constant. For example, if A = 0, the address of the logical block has the same value as the address of 990 physical blocks capable of storing data. However, A may be an integer greater than or equal to 1 (that is, the logical block address need not be the same value as the physical block address).

  As the logical address of the dedicated file area 22 in FIG. 3 described above, the logical address determined in this way is stored in the memory in the controller 15.

  When the controller 15 accesses the flash memory 42 of the memory stick 1, the address of the physical block corresponding to the address of the designated logical block among the addresses in the non-access address table 70 of FIG. 6 (when A = 0) Is added to the address of the physical block corresponding to the address of the designated logical block by adding the number of addresses having a smaller address number than the address of the designated logical block).

  That is, for example, when the address (100 + A) of a logical block is designated, and three physical blocks of physical blocks with address numbers 1 to 99 are inaccessible, the non-access address table 70 Since there are three addresses having an address number smaller than the physical block address 100 corresponding to the logical block address (100 + A), the address is converted to the logical block address 103 by adding 3 to 100.

  FIG. 8 is a flowchart showing processing executed by the controller 15 of the player 11 of FIG. 2 by controlling the control block 41 of the memory stick 1 based on the operation of the playback button of the operation unit 14. In this process, first, the dedicated file area 22 (FIG. 3) in the system area 20 of the flash memory 42 is accessed, and information in the dedicated file area 22 is read (step S1).

  Then, the information of the sector number of the dedicated file system management area 32 (FIG. 3) in the data area 30 is acquired, and the dedicated file system management area 32 is accessed based on the information, and the dedicated data area 31 (FIG. 3). Information about the first file 31 (1) is read (step S2).

  Subsequently, it is determined whether or not the read information is about the file 31 (X) to be read this time (the X-th test question) (step S3). If no, information on the next files 31 (2), 31 (3),... Is read one by one (step S4), and the determination in step S3 is repeated.

  When the answer is yes, the information on the start sector and size of the data of the file 31 (X) to be read is acquired (step S5), and the continuous data corresponding to the size is read from the start sector in the dedicated data area 31. As a result, the data of the file 31 (X) is read (step S6). Then, the process ends.

  As described above, the data of the file 31 (X) read from the flash memory 42 is supplied from the memory stick 1 to the player 11 and output from the earphone terminal 18 of the player 11 as an audio signal. Accordingly, the examinee of the hearing test can reproduce the test questions from the memory stick 1 and take the test by using one player 11 each.

  Next, how data is reproduced from the memory stick 1 by the FAT file system without using the player 11 will be described. FIG. 9 is a flowchart showing a process of reproducing data from the memory stick 1 by the FAT file system. In this process, first, the memory stick 1 is recognized as a memory stick formatted by the FAT file system by reading the boot area 33, FAT 34, and root directory 35 in the data area 30 (step S11).

  Subsequently, the determination of whether or not the information about the folder to be read (here, the folder “A” in FIG. 3) has been read is repeated while reading the information about the folder from the root directory 35 one by one (step S12, S13).

  When the answer is yes, the folder area 36 is accessed, and it is determined whether or not the information about the file to be read (here, the file “A” in FIG. 3) has been read out from the folder area 36. Repeated while reading information about “E” one by one (steps S14 to S16).

  If the answer is yes, information on the start cluster and size for the file “A” is acquired (step S17), and data for one cluster is read based on the acquired cluster information (step S18). Subsequently, based on the acquired size information, it is determined whether or not reading of the file “A” is completed (step S19).

  If no, the information of the next cluster number for the file “A” is obtained one by one from the FAT 34 (step S20), and the process of step S18 and the determination of step S19 are repeated. And if it becomes YES, a process will be complete | finished.

  In this way, data can be reproduced from the memory stick 1 also by the FAT file system. However, as described above, the start cluster of the file in each folder and each subsequent cluster are independent of the data arrangement of the files 31 (1) to 31 (N) in the dedicated data area 31. Or, since it is a cluster at an appropriate position in the dedicated file system management area 32, the data reproduced by the FAT file system is an array of data in the dedicated data area 31 (voice data of the original test problem). The changed data.

  Therefore, even if a test question is reproduced from the memory card 1 in a general system equipped with an OS such as Windows (registered trademark), it is recognized as random voice data different from the voice data of the test question. The problem never leaks.

  Thus, according to the Memory Stick 1, the memory stick stores test questions in a data format that can be played back only by a dedicated file system that is not compatible with the FAT file system, and then formats the memory stick that has been formatted by the FAT file system. It realizes a recognizable state. Therefore, the test questions can be stored in an existing memory stick using the FAT file system in a data format incompatible with the FAT file system. Thereby, highly confidential data such as test questions can be safely stored in the memory stick while maintaining the FAT file system function of the existing memory stick.

  In addition, since the data reproduced by the FAT file system is data obtained by changing the data arrangement in the dedicated data area 31, the FAT file system does not add an area for storing data other than the dedicated data area 31. The reproduced data can be different from the data reproduced by the dedicated file system.

  Further, in the memory stick 1, as shown in FIG. 2, a dedicated file area 22 indicating a method of accessing the dedicated file system management area 32 is provided in the system area 20 of the flash memory.

  Therefore, if the data reproduced from the data area 30 of the flash memory 42 of the memory stick 1 is illegally copied to another memory stick by the FAT file system and the test question is reproduced on the player 11 from the other memory stick, Since the area 22 is not included, the dedicated file system management area 32 cannot be accessed, and as a result, the dedicated data area 31 cannot be accessed to reproduce the test question. In addition, when file data is replicated to another memory card in a system such as Windows (registered trademark), normally the cluster of each file is arranged neatly in ascending order, so the data arrangement of the original memory card cannot be restored. . Therefore, unauthorized duplication of the memory stick 1 can be prevented, and the test questions can be stored safely in this respect as well.

  As described with reference to FIGS. 4 and 5, the data of each file is linearly arranged in units of sectors in the dedicated data area 31, and each file is also stored in the dedicated file system management area 32. Since the file information necessary for access is linearly arranged in units of sectors, the playback device that plays back data from the memory stick 1 simply accesses the dedicated file system management area 32 and stores the file data to be played back. And the connection of data in the file can be determined. That is, the storage position of the file data is detected and the connection of the data in the file is determined without searching for the file entry or referring to the FAT as in the processing by the conventional FAT file system (FIG. 11). Can do.

  As a result, even in an inexpensive reproducing apparatus having a low processing capacity and a small memory capacity, the data stored in the memory stick 1 can be quickly taken out and reproduced.

  Further, in the dedicated file system management area 32, in addition to the file information, commands for each file in the dedicated data area are linearly arranged in units of sectors (that is, the file information is stored in a command interpreter format). Therefore, the processing load on the playback device can be further reduced.

  The player 11 reproduces data from the memory stick 1 using a dedicated file system, so that the data can be quickly taken out from the memory stick 1 and reproduced even if the processing capacity is low and the memory capacity is small. Therefore, the manufacturing cost of the player 11 can be reduced by using the controller 15 of the player 11 having a low processing capacity and a small memory capacity.

  Further, since the player 11 performs conversion to the physical block address using the non-access address table 70 shown in FIG. 6, even if the memory capacity is small, the address of the logical block is designated and the memory stick 1 is read out. Data can be quickly retrieved and played back.

  In the above example, the management area for the FAT file system such as the boot area 33, the FAT 34, the root directory 35, and the folder area 36 is provided in the data area 30 of the memory stick 1. However, as another example, The FAT file system management area may not be provided in the data area 30 (only the dedicated data area 31 and the dedicated file system management area 32 are provided in the data area 30). Even in this case, as described with reference to FIGS. 4 and 5, the data stored in the memory stick 1 can be used in an inexpensive playback device (of course, the player 11) having a low processing capacity and a small memory capacity. Can be quickly taken out and played.

  In the above example, the present invention is applied to a memory stick storing a test question (audio data) and a dedicated player for reproducing the test question from the memory stick. However, not limited to this, data other than exam questions (eg personal information such as address, name, e-mail address, credit card number, etc.) is stored in a memory stick, and that data is played (displayed on the screen) on a dedicated player. May be.

  In the above example, the present invention is applied to a memory stick. However, the present invention may be applied to a memory card other than a memory stick such as SmartMedia (trademark) or CompactFlash (registered trademark).

It is a block diagram which shows the circuit structural example of the memory stick to which this invention is applied. It is a block diagram which shows the circuit structural example of the player to which this invention is applied. It is a figure which shows the format of the flash memory of the memory stick of FIG. FIG. 4 is a diagram showing details of a dedicated data area and a dedicated file system management area in FIG. 3. It is a figure which shows the mode of the storage of the file data to the exclusive data area | region of FIG. It is a figure which shows the non-access address table stored in the controller of the player of FIG. It is a figure which shows the data size at the time of supposing that the logical-physical conversion correspondence table was provided about the flash memory of the memory stick of FIG. It is a flowchart which shows the process which the controller of the player of FIG. 2 performs. 2 is a flowchart showing a process for reproducing data from the memory stick of FIG. 1 by a FAT file system. It is a figure which shows the format of the conventional memory card which employ | adopted the FAT file system. It is a flowchart which shows the data reproduction process by the FAT file system from the conventional memory card. It is a figure which shows a logical-physical conversion correspondence table.

Explanation of symbols

  1 Memory Stick, 11 Player, 12 Interface Block, 13 Bus, 14 Operation Unit, 15 Controller, 16 Decoder, 17 D / A Converter, 18 Earphone Terminal, 20 System Area, 21 Unique Information Area, 22 Dedicated File Area, 30 Data area, 31 dedicated data area, 32 dedicated file system management area, 33 boot area, 34 FAT, 35 root directory, 36 folder, 41 control block, 42 flash memory, 70 non-access address table

Claims (4)

The semiconductor memory has a dedicated data area for storing data of a dedicated file system different from the FAT file system, and a dedicated file system management area indicating a method for accessing the dedicated data area,
In the dedicated data area, the data of each file is stored in successive sectors according to the data reproduction order, starting from the start of the sector,
A memory card, wherein file information necessary for accessing each file in the dedicated data area is stored in the dedicated file system management area in successive sectors starting from the start of the sector. The memory card according to claim 1,
In the dedicated file system management area, in addition to the file information, a command for each file in the dedicated data area is stored in successive sectors starting from the start of the sector. . The semiconductor memory has a dedicated data area for storing data of a dedicated file system different from the FAT file system, and a dedicated file system management area indicating an access method to the dedicated data area. In the dedicated data area, The data of each file is stored in consecutive sectors according to the data playback order starting from the start of each sector, and is necessary for accessing each file in the dedicated data area in the dedicated file system management area In a playback device for playing back data from memory cards stored in successive sectors, each of which has a file information as the start position of each sector,
A first process for accessing the dedicated file system management area;
A playback apparatus comprising: processing means for performing a second process of reading continuous data from the dedicated data area based on the file information in the dedicated file system management area. The playback device according to claim 3, wherein
Of the physical blocks in the semiconductor memory of the memory card, a table storing addresses of physical blocks set to be inaccessible;
An address number arranged in ascending order from the smallest address number of a physical block capable of storing data among physical blocks in the semiconductor memory is determined as an address of the logical block, and when accessing the semiconductor memory, The address of the physical block is obtained by adding the number of addresses having an address number smaller than the address of the physical block corresponding to the address of the designated logical block to the address of the physical block corresponding to the designated logical block. And a processing means for performing conversion into a playback device.

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