# US 8,751,734 B2 · Semiconductor memory card access apparatus, a computer-readable recording medium, an initialization method, and a semiconductor memory card > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,751,734 B2 - Document ID: US8751734B2 - Status: Granted - Kind: B2 - Application number: 13/898,814 - Filed: 2013-05-21 - Published: 2013-10-10 - Granted: 2014-06-10 - Earliest claimed: 1999-10-21 - Assignees: Panasonic Corporation - Applicants: Panasonic Corporation - Inventors: Takuji Maeda; Teruto Hirota - Web page: https://patentgrep.com/patent/US8751734B2 ## CPC - G06F 3/0644: {Management of space entities, e.g. partitions, extents, pools} - G06F 3/0613: {in relation to throughput} - G06F 3/0616: {in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]} - G06F 3/064: {Management of blocks} - G06F 3/0643: {Management of files} - G06F 3/0652: {Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket} - G06F 3/0679: {Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]} - G06F 12/0223: {User address space allocation, e.g. contiguous or non contiguous base addressing} - G06F 12/0246: {in block erasable memory, e.g. flash memory} - G06F 12/1433: {for a module or a part of a module} - G06F 2212/1016: Performance improvement - G06F 2212/2022: Flash memory - G06F 2212/7202: Allocation control and policies - G11B 20/00086: {Circuits for prevention of unauthorised reproduction or copying, e.g. piracy (indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00)} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A predetermined number of erasable blocks positioned at a start of a volume area in a semiconductor memory card are provided so as to include volume management information. A user area following the volume management information includes a plurality of clusters. A size of a partition control area from a master boot record & partition table sector to a partition boot sector is determined so that the plurality of clusters in the user area are not arranged so as to straddle erasable block boundaries. Since cluster boundaries and erasable block boundaries in the user area are aligned, there is no need to perform wasteful processing in which two erasable blocks are erased to rewrite one cluster. ## Claims ### Claim 1 An access apparatus for performing file access on a semiconductor memory module that has a memory area comprising of a plurality of sectors, by managing one or more sectors as a cluster, and managing one or more clusters as a file, some consecutive sectors in the memory area forming a block, the block being a smallest unit on which data erasure can be performed, the access apparatus comprising: a calculation unit operable to calculate a size of volume management information based on a number of clusters in the memory area that are to be managed, the volume management information including a master boot record, a partition table, partition boot sector information, and a file allocation table that indicates, for each file, links between clusters corresponding to the file; a reserving unit operable to reserve (1) a first area for recording the volume management information, (2) a second area for recording a block including a root directory entry, (3) a third area for recording user data, the first area being formed from blocks that are each larger in size than the calculated size of the volume management information, and (4) a backup area for recording attribute information of the file recorded therein, and the third area being formed from blocks following the first area; and a recording unit operable to record volume management information in the first area, and user data in the third area, wherein the recording unit is operable to record the master boot record and the partition table in a first sector of a first block in the first area and record the partition boot sector information, the file allocation table, and a predetermined number of reserved sectors which are used for padding the first area, such that a size of the first area is an integral multiple of the block size. ### Claim 2 (depends on 1) The access apparatus of claim 1, wherein: the attribute information indicates, as an attribute, at least one of music, image, game, and text. ### Claim 3 (depends on 1) The access apparatus of claim 1, further comprising an attribute determining unit operable to determine an attribute of the file by referring to the attribute information recorded in the backup area. ### Claim 4 (depends on 1) The access apparatus of claim 1, wherein: the attribute information is different from information defined in a File Allocation Table file system. ### Claim 5 (depends on 1) The access apparatus of claim 1, wherein: the backup area is a protected area that can only be accessed once an authenticity of the access apparatus has been verified. ### Claim 6 (depends on 1) The access apparatus of claim 1, wherein the backup area includes: a sub-backup area that has sectors which, when defective sectors appear in at least one of the first area and the third area, are to replace the defective sectors. ### Claim 7 (depends on 6) The access apparatus of claim 6, wherein: the recording unit is operable to record, in the sub-backup area, the attribute information of the file. ### Claim 8 A semiconductor memory module that has a memory area comprising of a plurality of sectors, by managing one or more sectors as a cluster, and managing one or more clusters as a file, some consecutive sectors in the memory area forming a block, the block being a smallest unit on which data erasure can be performed, the semiconductor memory module comprising: a first area for recording volume management information, a second area for recording a block including a root directory entry, a third area, being formed from sectors following the first area, for recording user data, and a backup area having attribute information of the file recorded therein, wherein the volume management information including a master boot record, a partition table, partition boot sector information, and a file allocation table that indicates, for each file, links between clusters corresponding to the file, the master boot record and the partition table are recorded in a first sector of a first block in the first area, and the partition boot sector information, the file allocation table, and a predetermined number of reserved sectors which are used for padding the first area are recorded in subsequent sectors such that a size of the first area is an integral multiple of the block size. ### Claim 9 (depends on 8) The semiconductor memory module of claim 8, wherein: the attribute information indicates, as an attribute, at least one of music, image, game, and text. ### Claim 10 (depends on 8) The semiconductor memory module of claim 8, wherein: the attribute information is different from information defined in a File Allocation Table file system. ### Claim 11 (depends on 8) The semiconductor memory module of claim 8, wherein the backup area includes: a protected area that can only be accessed once an authenticity of an access apparatus has been verified, and the attribute information is recorded in the protected area. ### Claim 12 (depends on 8) The semiconductor memory module of claim 8, further comprising: a sub-backup area that has sectors which, when defective sectors appear in at least one of the first area and the third area, are to replace the defective sectors. ### Claim 13 (depends on 12) The semiconductor memory module of claim 12, wherein: the attribute information of the file is recorded in the sub-backup area. ### Claim 14 A recording medium storing a program in a computer-readable format for causing a computer to perform file access on a semiconductor memory module that has a memory area comprising of a plurality of sectors, by managing one or more sectors as a cluster, and managing one or more clusters as a file, some consecutive sectors in the memory area forming a block, the block being a smallest unit on which data erasure can be performed, the recording medium having the computer perform the following steps of: calculating a size of volume management information based on a number of clusters in the memory area that are to be managed, the volume management information including a master boot record, a partition table, partition boot sector information, and a file allocation table that indicates, for each file, links between clusters corresponding to the file; reserving (1) a first area for recording the volume management information, (2) a second area for recording a block including a root directory entry, (3) a third area for recording user data, the first area being formed from blocks that are each larger in size than the calculated size of the volume management information, and (4) a backup area for recording attribute information of the file recorded therein, and the third area being formed from blocks following the first area; and recording volume management information in the first area, and user data in the third area, wherein the recording step records the master boot record and the partition table in a first sector of a first block in the first area and records the partition boot sector information, the file allocation table, and a predetermined number of reserved sectors which are used for padding the first area, such that a size of the first area is an integral multiple of the block size. ### Claim 15 An initialization method for initializing a computer to perform file access on a semiconductor memory module that has a memory area comprising of a plurality of sectors, by managing one or more sectors as a cluster, and managing one or more clusters as a file, some consecutive sectors in the memory area forming a block, the block being a smallest unit on which data erasure can be performed, the initialization method comprising the steps of: calculating a size of volume management information based on a number of clusters in the memory area that are to be managed, the volume management information including a master boot record, a partition table, partition boot sector information, and a file allocation table that indicates, for each file, links between clusters corresponding to the file; reserving (1) a first area for recording the volume management information, (2) a second area for recording a block including a root directory entry, (3) a third area for recording user data, the first area being formed from blocks that are each larger in size than the calculated size of the volume management information, and (4) a backup area for recording attribute information of the file recorded therein, and the third area being formed from blocks following the first area; and recording volume management information in the first area, and user data in the third area, wherein the recording step records the master boot record and the partition table in a first sector of a first block in the first area and records the partition boot sector information, the file allocation table, and a predetermined number of reserved sectors which are used for padding the first area, such that a size of the first area is an integral multiple of the block size.