JP2017187817A - Memory management device, memory management method and video recording/reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a memory management device, a memory management method and a video recording/reproducing device that can suppress lowering of use efficiency of a NAND memory.SOLUTION: A memory management device of an embodiment is the memory management device that classifies a memory block which a storage medium has into any block of a normal block, a congenital bad block which became bad during manufacturing, and an acquired bad block which became bad during using and that manages only the memory block classified into the normal block to be available, and the memory management device comprises a management unit. The management unit classifies the memory block other than the congenital bad block into either of the normal block or the acquired bad block according to processing time required for write processing or erasure processing performed to the memory block.SELECTED DRAWING: Figure 4

Description

  Embodiments described herein relate generally to a memory management device, a memory management method, and a video recording / playback device.

  A video recording / playback apparatus that records and plays back content such as a TV program needs to record and play back content in synchronization with timing controlled by an APC (Automatic Program Controller). APC controls the timing so that playback and recording of one frame is executed in 33 msec. If the video recording / playback apparatus cannot synchronize with the control timing of the APC, content recording and playback cannot be performed normally. Both of these are factors that cause broadcast accidents, and such broadcast accidents become a serious social problem. Therefore, the video recording / playback apparatus needs to be reliably controlled so that it can be synchronized with the control timing of the APC at the time of content recording and playback.

  The video recording / playback apparatus includes a plurality of nonvolatile storage media, and records content by recording video data on these storage media. One of storage media used for recording such content is a NAND flash memory (hereinafter referred to as “NAND memory”). A NAND memory is a type of flash memory, and has the advantage that the circuit scale is smaller than that of a NOR flash memory and the capacity can be increased at low cost. In the NAND memory, a congenital defective block (hereinafter referred to as a “congenital bad block”) that has already become a defective block at the time of shipment from the factory, and processes such as writing and data erasing are repeatedly performed by the use of the user. Thus, there is an acquired defective block (hereinafter referred to as “acquired bad block”) which becomes a defective block. In general, a storage device including a NAND memory has a function of managing each block of the NAND memory and preventing a block that has become a defective block from being used thereafter.

  On the other hand, recent NAND memories tend to vary in performance from one storage element to another due to the effects of miniaturization and large capacity. Specifically, there is a variation in the time (hereinafter referred to as “completion time”) until processing such as writing, erasing, and reading of the storage element is completed. Therefore, in order to use such a NAND memory having a variation in performance, it is necessary to set a longer time for waiting for the completion of the processing (hereinafter referred to as “waiting time”) for these processes than before. is there. As described above, the video recording / playback apparatus needs to synchronize with the control timing of the APC in the process of recording, outputting, and playing back the content. . However, setting a long standby time degrades the processing performance, which may cause a problem that the simultaneous recording output and the number of reproduction cannot be satisfied.

  On the other hand, if the standby time is set short without sufficiently considering the performance variation of each storage element of the NAND memory, a normal block (hereinafter referred to as a “normal block”) is erroneously an acquired bad block. May be judged. As a result, there is a possibility that the usage efficiency of the NAND memory is remarkably deteriorated and the service life is shortened.

JP 2009-223876 A JP 2008-192266 A JP 2012-238259 A

  The problem to be solved by the present invention is to provide a memory management device, a memory management method, and a video recording / playback device capable of suppressing a decrease in use efficiency of a NAND memory.

  In the memory management device of the embodiment, the memory block included in the storage medium is any of a normal block, an innate bad block that has failed during manufacturing, and an acquired bad block that has failed in use. A memory management device that classifies and manages only the memory blocks classified as the normal blocks, and has a management unit. The management unit classifies the memory block other than the congenital bad block as the normal block or the acquired bad block according to the processing time required for the writing process or the erasing process performed on the memory block. .

Schematic which shows the outline | summary of the broadcast system 100 comprised using the video recording / reproducing apparatus 1 of 1st Embodiment. FIG. 3 is a functional block diagram showing a specific example of a functional configuration of the video recording / playback apparatus 1. The functional block diagram which shows the detail of a function structure of the memory | storage part 13 with which the video recording and reproducing apparatus 1 is provided. The functional block diagram which shows the detail of a function structure of the memory management part 40 with which the memory | storage part 13 is provided. The figure which shows the specific example of the memory information in 1st Embodiment. The figure which shows the specific example of the setting information in 1st Embodiment. 6 is a flowchart showing a flow of block management processing in the first embodiment. The figure which shows the specific example of the setting information in 2nd Embodiment. The figure which shows the specific example of the excess information in 2nd Embodiment. 9 is a flowchart showing a flow of block management processing in the second embodiment. The figure which shows the specific example of the setting information in 3rd Embodiment. The figure which shows the specific example of the accumulation information in 3rd Embodiment. 10 is a flowchart showing a flow of block management processing in the third embodiment. The flowchart which shows the flow of the return process in 4th Embodiment. The figure which shows the specific example of the setting information in 5th Embodiment. The flowchart which shows the flow of the return process in 5th Embodiment. The figure which shows the specific example of the setting information in 6th Embodiment. The figure which shows the specific example of the status information in 6th Embodiment. 14 is a flowchart showing a flow of return processing in the sixth embodiment. The flowchart which shows the flow of the return process in 7th Embodiment. The figure which shows the specific example of the setting information in 8th Embodiment. The figure which shows the specific example of the status information in 8th Embodiment. The flowchart which shows the flow of the return process in 8th Embodiment. The figure which shows the specific example of the status information in 9th Embodiment. The figure which shows the specific example of the status information in 9th Embodiment.

  Hereinafter, a memory management device, a memory management method, and a video recording / playback device according to embodiments will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic diagram showing an overview of a broadcast system 100 configured using the video recording / playback apparatus 1 (an example of a memory management apparatus) according to the first embodiment. The broadcast system 100 includes a video recording / playback device 1, a video acquisition device 2, a playback device 3, a non-linear editing machine 4, an operation terminal 5, a video confirmation monitor 6, a broadcast facility 7, and the like. The video recording / playback apparatus 1 is a device that records and plays back broadcast content.

  The video recording / playback apparatus 1 records and plays back content in synchronization with a timing of 33 msec per frame controlled by APC. Specifically, the video recording / playback apparatus 1 inputs the video signal output from the video acquisition apparatus 2 or the playback apparatus 3 to the own apparatus. The video signal is a signal for displaying a video that is being captured or reproduced, and is a signal that is continuously output in time series (hereinafter referred to as “stream”). The video recording / playback apparatus 1 generates video data by encoding a video signal input to the apparatus and converting it into digital data. On the other hand, the video recording / playback apparatus 1 acquires video data in a file format (hereinafter referred to as “video file”) from the nonlinear editor 4. The video recording / playback apparatus 1 records content by storing the generated video data and the acquired video file as broadcast video data (hereinafter referred to as “content data”).

  Also, the video recording / playback apparatus 1 generates content video signals by reading out and playing back the content data stored in the apparatus as necessary. The video recording / playback apparatus 1 outputs the generated video signal as a stream to a display device such as the video confirmation monitor 6 or the broadcasting equipment 7.

  The video acquisition device 2 is a device that acquires video as content. For example, the video acquisition device 2 is a photographing device such as a video camera. The video acquisition device 2 generates a video signal by capturing an image of a subject serving as broadcast content, and outputs the video signal to the video recording / playback device 1 as a stream.

  The playback device 3 is a device that plays back video recorded on various recording media. The playback device 3 generates a video signal by playing back the video and outputs the video signal to the video recording / playback device 1 as a stream. The recording medium 8 is a recording medium capable of recording video. For example, the recording medium 8 is a recording medium such as an 8 mm film, a video tape, or a semiconductor memory.

  The non-linear editing machine 4 is a terminal for performing non-linear editing on a video file. The non-linear editing machine 4 transmits the edited video file to the video recording / playback apparatus 1.

  The operation terminal 5 is a terminal device used for operating the video recording / playback apparatus 1. The user of the video recording / playback apparatus 1 can input an operation instruction for each function of the video recording / playback apparatus 1 and an operation setting for each function by operating the operation terminal 5.

  The video confirmation monitor 6 is a monitor device for confirming the video of the content being reproduced by the video recording / reproducing apparatus 1. The video confirmation monitor 6 is configured using a display device such as a CRT (Cathode Ray Tube) display, a liquid crystal display, or an organic EL (Electro-Luminescence) display. The video confirmation monitor 6 and the broadcasting equipment 7 input the video signal of the content being played output from the video recording / playback apparatus 1 to itself. The video confirmation monitor 6 displays the video of the content being played back by the video recording / playback device 1 based on the video signal input to the device itself.

  The broadcast facility 7 broadcasts on-air the video of the content being played back by the video recording / playback device 1 based on the video signal input to the device itself. In the following, in order to simplify the description, the video recording / playback apparatus 1 is information such as a video signal, a video file, and content data acquired or generated by recording or playback, and is a signal or data of the video itself to be displayed. Information including the image information is collectively referred to as video information. On the other hand, information relating to control of operations such as recording and playback of the video recording / playback apparatus 1 is referred to as control information.

  FIG. 2 is a functional block diagram showing a specific example of the functional configuration of the video recording / playback apparatus 1. The video recording / playback apparatus 1 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected by a bus, and executes a video recording / playback program. The video recording / playback apparatus 1 functions as a device including a main control unit 11, a recording output unit 12, a storage unit 13, a playback unit 14, and a transmission unit 15 by executing a video recording / playback program. Note that all or part of the functions of the video recording / playback apparatus 1 may be realized by using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). Good. The video recording / playback program may be recorded on a computer-readable recording medium. The computer-readable recording medium is, for example, a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, or a storage device such as a hard disk built in the computer system. The video recording / playback program may be transmitted via a telecommunication line.

  The main control unit 11 controls operations related to recording and playback of content in the video recording / playback apparatus 1 by transmitting / receiving control information to / from the recording output unit 12, the storage unit 13, and the playback unit 14. In FIG. 2, broken line arrows represent input / output of control information, and solid line arrows represent input / output of video information.

  The recording output unit 12 inputs and outputs video information with an external device. Specifically, the recording output unit 12 inputs a video signal output from the video acquisition device 2 or the playback device 3 to the own device when content is recorded. When recording with a video file, the recording output unit 12 acquires the video file from the nonlinear editing machine 4. The recording output unit 12 encodes and compresses the video signal input to the own apparatus using an encoding method such as MPEG-2 (Moving Picture Experts Group Phase 2) and converts the video signal into video data. In addition, the recording output unit 12 performs processing such as MXF (Material Exchange Format) analysis on the acquired video file and video data, thereby converting the video file and video data into a format for handling as content data. .

  The recording output unit 12 outputs the content data generated in this way to the storage unit 13 via the transmission unit 15. The recording output unit 12 acquires content data requested from an external device such as the nonlinear editing machine 4 or the operation terminal 5 from the storage unit 13 via the transmission unit 15. The recording output unit 12 converts the acquired content data into a file format and transmits it to the requesting external device. Hereinafter, sending content data to an external device in a file format is referred to as file output.

  The storage unit 13 is configured using a storage device such as a magnetic hard disk device or a semiconductor storage device. The storage unit 13 stores the content data output from the recording output unit 12, reads out the requested content data, and reads the read content data via the transmission unit 15 into the recording output unit 12 and the playback unit 14. To other functional units.

  The playback unit 14 acquires content data to be played back from the storage unit 13 via the transmission unit 15. The playback unit 14 generates a video signal by playing back the acquired content data by a method according to the encoding method. The reproduction unit 14 outputs the generated video signal as a stream to a display device such as the video confirmation monitor 6 or the broadcasting facility 7.

  The transmission unit 15 performs video information transfer processing among the recording output unit 12, the storage unit 13, and the reproduction unit 14. Specifically, the transmission unit 15 outputs content data output from the recording output unit 12 to the storage unit 13 during content recording, and content output from the storage unit 13 during content playback. The data is output to the playback unit 14.

  In FIG. 2, the recording output unit 12, the storage unit 13, the playback unit 14, and a plurality of arrows representing input / output of video information are displayed. The video recording / playback apparatus 1 records and plays back a plurality of contents. It is shown that it is possible to carry out in parallel. Hereinafter, a unit in which the video recording / playback apparatus 1 records and plays back content is referred to as a channel.

  FIG. 3 is a functional block diagram showing details of the functional configuration of the storage unit 13 included in the video recording / playback apparatus 1. In FIG. 3, broken line arrows mainly represent input / output of video information, and solid line arrows mainly represent input / output of control information. The storage unit 13 includes a memory unit 10, a memory controller 20, a content management unit 30, and a memory management unit 40.

  The memory unit 10 is configured using one or more NAND memories. The memory unit 10 includes a content data storage unit 101 that stores content data on one or more NAND memories. The memory unit 10 has a content management information storage unit 102 that stores content management information. The content management information is information necessary for managing the recorded content data. Specifically, the content management information includes correspondence between content data and a memory block (or page) that stores the content data, and attributes of the recorded content (for example, playback time, encoding method, title, etc.) Information) is included. For example, the content management information is generated by MFX analysis of the recording output unit 12 at the time of content recording, and is referred to by the content management unit 30 at the time of content reproduction. The content management information storage unit 102 may be configured using a NAND memory, or may be configured using a storage medium other than the NAND memory.

  The memory controller 20 includes an input / output unit 21 and a memory control unit 22. The input / output unit 21 acquires content data from the recording output unit 12 via the transmission unit 15 during content recording. The input / output unit 21 outputs the acquired content data to the content management unit 30. On the other hand, the input / output unit 21 acquires the content data read from the memory unit 10 via the content management unit 30 when reproducing the content. The input / output unit 21 outputs the acquired content data to the playback unit 14 via the transmission unit 15.

  The memory control unit 22 transmits / receives control information to / from the main control unit 11, and inputs / outputs control information to / from other function units of the storage unit 13, thereby other function units of the storage unit 13. To control the operation.

  The content management unit 30 includes a content data input / output unit 31 and a content control unit 32. The content data input / output unit 31 inputs / outputs content data between the memory unit 10 and the memory controller 20. Specifically, the content data input / output unit 31 acquires content data from the input / output unit 21 during content recording, and stores the acquired content data in the content data storage unit 101. In addition, the content data input / output unit 31 acquires content data from the content data storage unit 101 and outputs the acquired content data to the input / output unit 21 during content playback. The content data input / output unit 31 uses, as access information, control information related to access (specifically, processing such as writing, reading, deleting, and data erasing) performed on the NAND memory constituting the content data storage unit 101. Output to the memory management unit 40.

  The content control unit 32 inputs / outputs control information (including content management information) between the memory unit 10 and the memory controller 20 and controls the operation of the content data input / output unit 31 based on the acquired control information. . Specifically, the content control unit 32 acquires content management information related to content data to be recorded from the recording output unit 12 via the main control unit 11 and the memory control unit 22 during content recording. For example, the content control unit 32 stores the content data to be recorded based on the acquired content management information and the content management information on the recorded content data stored in the content management information storage unit 102. To decide. The content control unit 32 controls the content data input / output unit 31 so that content data to be recorded is stored in a predetermined storage area determined as a storage destination, and the content management information to be recorded is stored in the content management information. The data is stored in the storage unit 102.

  In addition, the content control unit 32 acquires the recorded content management information from the content management information storage unit 102 when reproducing the content. The content control unit 32 identifies the content data to be played based on the acquired content management information, and controls the content data input / output unit 31 so that the content data to be played is read from the storage area indicated by the content management information. To do. In addition, the content control unit 32 secures an empty area of the NAND memory by performing processing such as deletion of content data and data erasure on a block holding the deleted data as necessary.

  The memory management unit 40 manages each block except the congenital bad block as a normal block or an acquired bad block in the NAND memory constituting the content data storage unit 101 of the memory unit 10. Hereinafter, the process of managing each block of the NAND memory as a normal block or an acquired bad block is referred to as a block management process.

  FIG. 4 is a functional block diagram showing details of the functional configuration of the memory management unit 40 included in the storage unit 13. The memory management unit 40 includes a memory information storage unit 41, a setting information storage unit 42, a memory information acquisition unit 43, and a block state management unit 44. The memory information storage unit 41 and the setting information storage unit 42 are configured using a storage device such as a magnetic hard disk device or a semiconductor storage device. The memory information storage unit 41 stores memory information. The memory information includes information related to the state of the NAND memory (hereinafter referred to as “state information”) and access information of the NAND memory. Specifically, the status information is information indicating whether each block is in a congenital bad block, a normal block, or an acquired bad block. The setting information storage unit 42 stores setting information. The setting information is information indicating settings necessary for block management processing of the NAND memory. The setting information storage unit 42 stores predetermined setting information in advance.

  FIG. 5 is a diagram illustrating a specific example of memory information in the first embodiment. For example, the memory information is stored as a state information table 411 and an access information table 412 shown in FIG. The state information table 411 has a state information record for each block ID. The status information record has each value of block ID and block status. The block ID is identification information of each block of the NAND memory. For example, the block ID may be represented by a memory address of each block. The block state indicates whether the block indicated by the block ID is a normal block, an innate bad block, or an acquired bad block.

  The access information table 412 has an access information record for each access time. The access information record has values of access time, access type, access target block ID, completion time, and completion status. The access time represents the time when access to the NAND memory occurs. The access type represents the type of access that occurred at the access time. The access target represents a block ID to be accessed at the access time. The completion time represents the completion time of access that occurred at the access time. The completion status represents the success or failure of the access that has occurred. The access information table 412 may be configured as a table that holds the latest access information for each block. In that case, the access information table 412 may be integrated into the state information table 411.

  FIG. 6 is a diagram illustrating a specific example of setting information according to the first embodiment. For example, the setting information is stored as a setting information table 421 shown in FIG. The setting information table 421 is a table that holds a threshold value of a completion time for a writing or data erasing process performed on the NAND memory. The setting information table 421 has a setting information record for each setting ID. The setting information record has values of setting ID and completion time threshold. The setting ID is information for identifying a combination of threshold values for writing processing and data erasing processing (hereinafter referred to as “setting pattern”). The completion time threshold represents a completion time threshold set for each of the writing and data erasing processes. The setting information table 421 in FIG. 6 is an example of setting information having two setting patterns having a relationship of a <b and A <B. In the video recording / playback apparatus 1, any setting pattern used for the block management process is selected in advance, and the video recording / playback apparatus 1 executes the block management process using the setting value of the preselected setting pattern. To do.

  Returning to the description of FIG. The memory information acquisition unit 43 acquires memory information and stores it in the memory information storage unit 41. Generally, in the NAND memory at the time of shipment from the factory, state information related to the congenital bad block is recorded in a predetermined block. The memory information acquisition unit 43 reads state information regarding the congenital bad block from a predetermined block of the NAND memory at the start of use of the own device, and stores the read state information in the memory information storage unit 41 as memory information. . On the other hand, the memory information acquisition unit 43 stores the access information output from the content data input / output unit 31 in the memory information storage unit 41 as memory information.

  The block state management unit 44 performs block management processing based on the setting information and the memory information. Specifically, the block state management unit 44 manages a block other than the congenital bad block as a normal block or an acquired bad block based on the access completion time for each block. The block state management unit 44 updates the content management information based on the result of the block management process. The content management information may be updated by the content control unit 32. In this case, the block state management unit 44 may notify the content control unit 32 of the result of the block management process by transmitting control information via the memory control unit 22.

  FIG. 7 is a flowchart showing the flow of block management processing in the first embodiment. Here, the flow of processing will be described assuming that the setting information is registered with the contents of the setting information table 421 shown in FIG. First, the content data input / output unit 31 performs a write or data erase process on the NAND memory (step S101). The block state management unit 44 determines whether the setting information used for the block management process is set to “setting 1” or “setting 2” (step S102).

  When the setting pattern is set to “setting 1” (step S102: “setting 1”), the block state management unit 44 refers to the access information of the access (write or data erase) and completes the access completion time. Is over the completion time threshold defined in “setting 1” (write: “a”, erase: “A”) (step S103). When the completion time exceeds the completion time threshold (step S103—YES), the block state management unit 44 defines the block that is the access target (hereinafter referred to as “access target block”) as an acquired bad block. Determination is made (step S104).

  On the other hand, when the completion time is equal to or less than the completion time threshold defined in “Setting 1” (step S103—NO), the block state management unit 44 determines that the access target block is a normal block (step S105).

  On the other hand, when the setting pattern is set to “setting 2” in step S102 (step S102: “setting 2”), the block state management unit 44 accesses the access information for the access (write or data erase). , It is determined whether or not the access completion time exceeds the completion time threshold defined by “setting 2” (write: “b”, erase: “B”) (step S103). When the completion time exceeds the completion time threshold (step S103—YES), the block state management unit 44 determines that the access target block of the access is an acquired bad block (step S104).

  On the other hand, when the completion time is equal to or less than the completion time threshold defined in “Setting 2” (step S103—NO), the block state management unit 44 determines that the access target block is a normal block (step S105).

  After performing such determination processing, the block state management unit 44 updates the state information of the access target block according to the determination result. Specifically, the block state management unit 44 refers to the state information table 411 and selects a state information record having a block ID indicating the access target block. Since the writing and data erasing processes are performed on the blocks managed as normal blocks, the block status value of the status information record selected here is “normal block”. When it is determined that the access target block is an acquired bad block, the block state management unit 44 updates the block state value of the selected state information record from “normal block” to “acquired bad block”.

  The video recording / playback apparatus 1 according to the first embodiment configured as described above determines that the access target block is a normal block or a subsequent block based on the time (completion time) until the writing process or data erasing process to the NAND memory is completed. A block state management unit 44 that manages any of the natural bad blocks is provided. According to such a configuration, the video recording / playback apparatus 1 can suppress a decrease in the use efficiency of the NAND memory by selecting a setting pattern according to the usage status of the own apparatus.

  In the present embodiment, it is assumed that the block management process is executed as a process different from the time-out process for accessing the NAND memory in the content data input / output unit 31. Specifically, the memory management unit 40 determines the block state based on the access information notified from the content data input / output unit 31. This means that the memory management unit 40 determines the block state based on the result of access by the content data input / output unit 31. In this case, the waiting time of the content data input / output unit 31 may be set as the completion time threshold, or a time shorter than the waiting time may be set.

  On the other hand, the block management process described above may be directly incorporated in the timeout process in the content data input / output unit 31. In this case, the completion time threshold is the standby time. In this case, the determination of the completion time can be processed simultaneously with the memory access, but the processing load on the content data input / output unit 31 may increase. Therefore, when the content data input / output unit 31 does not have sufficient processing capability, the block management process is desirably executed separately from the timeout process.

(Second Embodiment)
The video recording / playback apparatus 1 of the second embodiment is different from the video recording / playback apparatus 1 of the first embodiment in that a block state management unit 44a (not shown) is provided instead of the block state management unit 44. Note that the functional configuration of the video recording / playback apparatus 1 of the second embodiment is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  FIG. 8 is a diagram illustrating a specific example of the setting information in the second embodiment. The setting information in the second embodiment is stored as, for example, a first setting information table 422 and a second setting information table 423 shown in FIG. The first setting information table 422 has one first setting information record. The first setting information record has each value of the completion time threshold value for each processing of writing and data erasing.

  The second setting information table 423 includes a second setting information record for each mode ID. The 2nd setting information record has each value of mode ID and an excess frequency threshold. The mode ID is identification information of the operation mode of the block management process. The operation mode of the block management process includes the first mode in which the completion time of the write or data erasure process is evaluated by the total number of accesses that have exceeded the completion time threshold, and access that has continuously exceeded the completion time threshold. There is a second mode that evaluates by number. Either the first mode or the second mode is set in advance in the video recording / playback apparatus 1, and the video recording / playback apparatus 1 executes block management processing in the preset operation mode. The excess number threshold value is a threshold value of the number of times that the completion time of the writing or data erasing processing for the NAND memory exceeds the completion time threshold set for each processing. A threshold value corresponding to each operation mode is set as the excess number threshold value.

  The block state management unit 44a generates excess information for each block based on the access information. The excess information is information indicating the number of times that the access completion time for each block has exceeded the completion time threshold. The block state management unit 44a stores the generated excess information in the memory information storage unit 41. The block state management unit 44a updates the current excess information based on the access information of the newly generated access in response to the occurrence of a new writing or data erasing process.

  FIG. 9 is a diagram illustrating a specific example of excess information in the second embodiment. For example, the excess information is stored as an excess information table 413 shown in FIG. The excess information table 413 has an excess information record for each block ID. The excess information record has values of a block ID, a continuous excess number, and a total excess number. The continuous excess count represents the number of times that the completion time of access (writing or data erasure) for the block indicated by the block ID has continuously exceeded the completion time threshold. The total excess number represents the cumulative number of times that the access completion time for the block indicated by the block ID exceeds the completion time threshold.

  The block state management unit 44a performs block management processing based on the setting information and the memory information. Specifically, the block state management unit 44a manages a block other than the congenital bad block as a normal block or an acquired bad block based on the completion time of access to each block and excess information.

  FIG. 10 is a flowchart illustrating a flow of block management processing in the second embodiment. Here, the flow of processing will be described assuming that the setting information is registered with the contents of the first setting information table 422 and the second setting information table 423 shown in FIG. First, the content data input / output unit 31 performs writing or data erasing processing on the NAND memory (step S201). The block state management unit 44a refers to the access information of the access, and determines whether or not the access completion time exceeds the completion time threshold (write: “a”, erase: “A”) (step S1). S202).

  When the completion time is equal to or less than the completion time threshold (step S202—NO), the block state management unit 44a determines that the access target block is a normal block (step S203). On the other hand, when the completion time exceeds the completion time threshold (step S202—YES), the block state management unit 44a updates the excess information (step S204), and the operation mode of the own device is the first mode or the second mode. Which mode is set is determined (step S205). Here, it is assumed that “mode 1” registered in the second setting information table 423 is the first mode and “mode 2” is the second mode.

  When the operation mode of the own apparatus is set to the first mode (step S205: “mode 1”), the block state management unit 44a determines that the number of consecutive excesses of the access target block is defined as “mode 1”. It is determined whether or not the number-of-times threshold “b” is exceeded (step S206). When the continuous excess number exceeds the excess number threshold value (step S206—YES), the block state management unit 44a determines that the access target block is an innate bad block (step S207). On the other hand, when the continuous excess count is equal to or less than the excess count threshold (step S206—NO), the block state management unit 44a determines that the access target block is a normal block (step S203).

  On the other hand, when the operation mode of the own apparatus is set to the second mode in step S205 (step S205: “mode 2”), the block state management unit 44a determines that the total number of times the access target block is exceeded. It is determined whether or not the excess number threshold “B” defined in “mode 2” has been exceeded (step S208). If the total excess count exceeds the excess count threshold (step S208—YES), the block state management unit 44a determines that the access target block is an innate bad block (step S207). On the other hand, when the total excess count is equal to or less than the excess count threshold (step S208—NO), the block state management unit 44a determines that the access target block is a normal block (step S203).

  The video recording / playback apparatus 1 of the second embodiment configured in this way has exceeded the completion time threshold for the completion time of the write or data erasure processing for the NAND memory and the completion time of the access that occurred in the access target block. Based on the number of times, a block state management unit 44a that manages the access target block as either a normal block or an acquired bad block is provided. According to such a configuration, the video recording / playback apparatus 1 can suppress a decrease in the use efficiency of the NAND memory by selecting an operation mode according to the usage status of the own apparatus.

(Third embodiment)
The video recording / playback apparatus 1 of the third embodiment is different from the video recording / playback apparatus 1 of the first embodiment in that a block state management unit 44b (not shown) is provided instead of the block state management unit 44. Note that the functional configuration of the video recording / playback apparatus 1 of the third embodiment is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  FIG. 11 is a diagram illustrating a specific example of the setting information in the third embodiment. For example, the setting information in the third embodiment is stored as a third setting information table 424 shown in FIG. The third setting information table 424 has setting information records for each access type. The setting information record has each value of an access type, a completion time threshold value, an abnormality rate threshold value, and an increment value. The access type represents the type of access (write or data erase) that has occurred to the NAND memory. The completion time threshold represents a threshold of completion time set for each access type. The abnormality rate threshold value represents a threshold value for each access type of a rate at which access to each block becomes abnormal (hereinafter referred to as “abnormality rate”). The increment value represents an increment value when changing the completion time threshold value of each access type.

  The block state management unit 44b generates accumulated information of each block based on the access information. The cumulative information is information indicating the cumulative number of successful / unaccessed blocks. The block state management unit 44b stores the generated accumulated information in the memory information storage unit 41. The block state management unit 44b updates the current accumulated information based on the access information of the newly generated access in response to the occurrence of a new writing or data erasing process.

  FIG. 12 is a diagram illustrating a specific example of accumulated information in the third embodiment. For example, the cumulative information is stored as a cumulative information table 414 shown in FIG. The cumulative information table 414 has a cumulative information record for each block ID. The cumulative information record has values of block ID, cumulative normal number of times, and cumulative abnormal number of times. The accumulated normal number of times represents the number of times that the access that has occurred with respect to the block indicated by the block ID has been normally completed. The cumulative number of abnormal times represents the number of times that access that has occurred to the block indicated by the block ID becomes abnormal. The cumulative normal count and cumulative abnormal count hold the cumulative count for each access type (write or data erase).

  The block state management unit 44b performs block management processing based on setting information and memory information (including cumulative information). Specifically, the block state management unit 44b manages a block other than the congenital bad block as a normal block or an acquired bad block based on the completion time of access to each block and the accumulated information. The block state management unit 44b adjusts the completion time threshold based on the accumulated information.

  FIG. 13 is a flowchart showing the flow of block management processing in the third embodiment. Here, the flow of processing will be described assuming that the setting information is registered with the contents of the third setting information table 424 shown in FIG. First, the content data input / output unit 31 performs a write or data erase process on the NAND memory (step S301). The block state management unit 44b refers to the access information of the access, and determines whether or not the access completion time exceeds the completion time threshold (write: “a”, erase: “A”) (step S40). S302).

  When the completion time is equal to or less than the completion time threshold (step S302—NO), the block state management unit 44b updates the normal cumulative number (adds 1) (step S303) and determines that the access target block is a normal block (step) S304). On the other hand, when the completion time exceeds the completion time threshold value (step S302—YES), the block state management unit 44b updates (adds 1) the number of abnormal accumulations (step S305), and based on the updated accumulated information. Calculate the percentage of abnormalities. The block state management unit 44b determines whether or not the calculated abnormality ratio exceeds the abnormality ratio threshold (writing: “b”, erasure: “B”) (step S306).

  When the abnormal ratio is less than or equal to the abnormal ratio threshold (step S306-NO), the block state management unit 44b determines that the access target block is a normal block (step S304). On the other hand, when the abnormal ratio exceeds the abnormal ratio threshold value (step S306-YES), the block state management unit 44b increases the completion time threshold value by the increment value (step S307), and sets the access target block as an acquired bad block. (Step S308).

  The video recording / playback apparatus 1 of the third embodiment configured as described above is based on the completion time of the writing or data erasing processing on the NAND memory and the success rate (abnormality rate) of the access that has occurred in the access target block. A block state management unit 44b that manages the access target block as either a normal block or an acquired bad block is provided. According to such a configuration, the video recording / playback apparatus 1 can suppress a decrease in the usage efficiency of the NAND memory by setting the abnormality ratio threshold value according to the usage status of the own apparatus.

  In the video recording / playback apparatus 1 of the third embodiment, the block state management unit 44b can increase the completion time threshold according to the abnormality rate. By providing such a configuration, the video recording / playback apparatus 1 can suppress the normal block from being excessively managed as an acquired bad block by the block management process.

(Fourth embodiment)
The video recording / playback apparatus 1 of the fourth embodiment differs from the video recording / playback apparatus 1 of the first embodiment in that a block state management unit 44c (not shown) is provided instead of the block state management unit 44. The functional configuration of the video recording / playback apparatus 1 of the fourth embodiment is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS.

  The block state management unit 44c is different from the block state management unit 44 in the first embodiment in that a return process is further executed in the block management process. The return process is a process for returning a block managed as an acquired bad block to a normal block based on a predetermined condition. In this case, the memory information in the fourth embodiment is stored as the state information table 411 and the access information table 412 shown in FIG. In this case, the setting information is stored as a first setting information table 422 shown in FIG.

  FIG. 14 is a flowchart showing the flow of return processing in the fourth embodiment. First, the block state management unit 44c refers to the state information and determines whether there is a block managed as an acquired bad block (step S401). When there is no block managed as an acquired bad block (step S401—NO), the block state management unit 44c ends the return process. On the other hand, when there is a block managed as an acquired bad block (step S401-YES), the block state management unit 44c generates access (write or data erase) to the block managed as an acquired bad block. (Step S402). The block state management unit 44c determines whether the completion time of the generated access is equal to or less than the completion time threshold (step S403).

  If the completion time of the generated access exceeds the completion time threshold (step S403—NO), the block state management unit 44c ends the return process. On the other hand, when the completion time of the generated access is less than or equal to the completion time threshold (YES in step S403), the block state management unit 44c determines that the access target block is a normal block and manages the block as a normal block ( Step S404). Specifically, the block state management unit 44c updates the block state value of the state information record corresponding to the block from “acquired bad block” to “normal block”.

  Note that the timing at which the above return processing is executed is arbitrary. For example, the return process may be executed every predetermined cycle, or may be executed according to the success or failure of the access that occurs to the NAND memory. Further, the return processing may be executed according to the processing cycle of each frame (hereinafter referred to as “FI” (Frame Interval)) at the time of content recording or playback. Further, not all acquired bad blocks that exist at a certain point in time need to be processed in a single return process. In a single return process, it is only necessary to process a number of acquired bad blocks that can be processed in accordance with the execution timing of the return process and the state of the video recording / playback apparatus 1, and the acquired bad blocks are processed in a plurality of return processes. It may be processed in a distributed manner.

  In step S402, an access to the return target block that is attempted to determine whether or not the acquired bad block (hereinafter referred to as “recovery target block”) to be returned is returned to a normal block ( Hereinafter, “test access”) may be both the writing process and the data erasing process, or may be one of them. For example, access may be performed according to the reason why the return target block is managed as an acquired bad block. Specifically, when the return target block is managed as an acquired bad block because the completion time of the write process exceeds the completion time threshold, the block state management unit 44c performs a write process on the return target block as a test access. You may only go. Similarly, when the restoration target block is managed as an acquired bad block because the completion time of the data erasing process exceeds the completion time threshold, the block state management unit 44c performs data erasing processing on the restoration target block as a test access. You may only go. As described above, when determining whether to return the return target block to the normal block based on the completion time of the test access according to the reason managed as the acquired bad block, for each return target block, the acquired Information indicating the reason for management as a bad block (hereinafter referred to as “reason information”) is required. For example, the reason information may be acquired by referring to the access information table 412 or may be acquired by holding the reason information of each block in the state information table 411.

  The video recording / playback apparatus 1 according to the fourth embodiment configured as described above is a block that performs a return process for returning the block to a normal block according to the result of access to the block managed as an acquired bad block. A state management unit 44c is provided. By providing such a configuration, the video recording / playback apparatus 1 can suppress a decrease in the use efficiency of the NAND memory. Specifically, the video recording / playback apparatus 1 can return a block managed as an acquired bad block due to a temporary abnormality as a normal block.

(Fifth embodiment)
The video recording / playback apparatus 1 of the fifth embodiment differs from the video recording / playback apparatus 1 of the fourth embodiment in that a block state management unit 44d (not shown) is provided instead of the block state management unit 44c. The functional configuration of the video recording / playback apparatus 1 is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  FIG. 15 is a diagram illustrating a specific example of setting information in the fifth embodiment. For example, the setting information in the fifth embodiment is stored as a first setting information table 422 shown in FIG. 8 and a fourth setting information table 425 shown in FIG. The fourth setting information table 425 includes a third setting information record for each processing type. The third setting information record has values of processing type and necessary resources. The processing type represents the type of processing that occurs in the video recording / playback apparatus 1. The necessary resource represents the amount of NAND memory resources required for one process of the process type.

  The fourth setting information table 425 in FIG. 15 indicates the necessary resources (an example of load information) for each processing type, the input amount of data (input) that the NAND memory can process per unit time, or the NAND memory per unit time. It is an example represented by the output amount (output) of the data which can be processed. As the information indicating the input / output performance of the NAND memory, a catalog specification of the NAND memory may be used, or a result of an actual load test may be used. Here, for simplicity of explanation, the upper limit of the data amount that can be input / output by the NAND memory per unit time is 100, and the data input / output amount per unit time required for one process of each processing type is 0-100. Represented by value. Such definition of the necessary resource is an example, and an index other than the data input / output performance may be used as the necessary resource. The necessary resource for “return processing” defined in the fourth setting information table 425 represents the input / output amount of data necessary for executing the return processing for one return target block.

  The block state management unit 44d determines a return target block based on the resource usage status in the own device and the setting information, and executes a return process on the acquired bad block determined as the return target block.

  FIG. 16 is a flowchart showing the flow of return processing in the fifth embodiment. First, the block state management unit 44d refers to the state information and determines whether there is a block managed as an acquired bad block (step S501). When there is no block managed as an acquired bad block (step S501-NO), the block state management unit 44d ends the return process. On the other hand, when there is a block managed as an acquired bad block (step S501-YES), the block state management unit 44d selects a restoration target block from among the blocks managed as acquired bad blocks. . A specific method for selecting the return target block is as follows.

  As described above, the video recording / playback apparatus 1 needs to record and play back content in synchronization with the timing of every 33 msec controlled by APC. For this reason, the video recording / playback apparatus 1 performs what type of processing (excluding return processing) and how much multiplicity (that is, the number of channels to be used) in the next FI before the processing in the next FI is started. ) Is scheduled in advance. Based on such a scheduling function, the block state management unit 44d calculates the sum of necessary resources for each process executed in the next FI (step S502). Specifically, the block state management unit 44d calculates the sum of necessary resources by multiplying the amount of necessary resources for processing scheduled for the next FI by the multiplicity of each processing and totaling them. Based on the total required resources in the next FI calculated in this way and the resources required for the return processing, the block state management unit 44d determines the number of return target blocks that can execute the return processing in the next FI (hereinafter referred to as “recovery target blocks”). , "The number that can be processed"). The block state management unit 44d selects a processable number of return target blocks from the blocks managed as acquired bad blocks (step S503).

  Subsequently, the block state management unit 44d performs test access (write or data erase) on the acquired bad block selected as the return target block (step S504). The block state management unit 44d determines whether or not the test access completion time is less than the completion time threshold (step S505).

  When the test access completion time is equal to or greater than the completion time threshold (step S505-NO), the block state management unit 44d ends the return process. On the other hand, when the test access completion time is less than the completion time threshold (step S505-YES), the block state management unit 44d determines that the return target block is a normal block and manages the block as a normal block (step S506). ).

  The video recording / playback apparatus 1 of the fifth embodiment configured as described above includes a block state management unit 44d that selects a return target block based on the resource usage status and setting information in the own apparatus. With such a configuration, the video recording / playback apparatus 1 can perform the return process without adversely affecting the recording or playback of content.

(Sixth embodiment)
The video recording / playback apparatus 1 of the sixth embodiment is different from the video recording / playback apparatus 1 of the fourth embodiment in that a block state management unit 44e (not shown) is provided instead of the block state management unit 44c. The functional configuration of the video recording / playback apparatus 1 is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  FIG. 17 is a diagram illustrating a specific example of setting information according to the sixth embodiment. For example, the setting information in the sixth embodiment is stored as a first setting information table 422 shown in FIG. 8 and a fifth setting information table 426 shown in FIG. The fifth setting information table 426 includes a fourth setting information record for each access type. The fourth setting information record has each value of the access type and the processing frequency threshold. The processing count threshold represents a threshold for the number of executions of return processing performed for one block.

  The block state management unit 44e determines a return target block based on the number of return processes executed so far for each block managed as an acquired bad block. In this case, in addition to the block state of each block, the block state management unit 44e manages the number of executions of return processing for each block as state information.

  FIG. 18 is a diagram illustrating a specific example of the state information in the sixth embodiment. For example, the state information in the sixth embodiment is stored as the state information table 411e shown in FIG. The state information table 411e is different from the state information table 411 in that the state information record has a value of the number of processes in addition to the block ID and the block state. The number of processes represents the number of executions of the return process performed in the past for the block indicated by the block ID. Specifically, the number of processes represents the number of accesses for each type of test access (write or data erase) in the return process. The block state management unit 44e updates the state information table 411e in accordance with the execution of the return process. Note that the total number of accesses by the test access and the access to the NAND memory by the content data input / output unit 31 may be used as the number of processes.

  FIG. 19 is a flowchart showing the flow of return processing in the sixth embodiment. First, the block state management unit 44e refers to the state information and determines whether there is a block managed as an acquired bad block (step S601). When there is no block managed as an acquired bad block (step S601-NO), the block state management unit 44e ends the return process. On the other hand, when there is a block managed as an acquired bad block (step S601-YES), the block state management unit 44e selects a restoration target block from among the blocks managed as acquired bad blocks.

  Specifically, the block state management unit 44e determines whether there is a block whose return processing number is less than the processing number threshold among the blocks managed as acquired bad blocks (step S602). ). If there is no block whose return processing count is less than the processing count threshold (step S602—NO), the block state management unit 44e ends the return processing. On the other hand, when there is a block whose return processing count is less than the processing count threshold (step S602-NO), the block state management unit 44e selects a block whose return processing count is less than the processing count threshold. (Step S603).

  Subsequently, the block state management unit 44e performs test access (write or data erase) on the acquired bad block selected as the return target block (step S604). The block state management unit 44e determines whether or not the test access completion time is less than the completion time threshold (step S605).

  When the test access completion time is equal to or greater than the completion time threshold (step S605-NO), the block state management unit 44e updates the state information by incrementing the number of executions of return processing for the block by 1 (step S606). , The return process is terminated. On the other hand, when the test access completion time is less than the completion time threshold (step S605-YES), the block state management unit 44e determines that the return target block is a normal block and manages the block as a normal block (step S607). ).

  The video recording / playback apparatus 1 of the sixth embodiment configured as described above includes a block state management unit 44e that determines a return target block based on the number of return processes executed so far for each block. . By including such a configuration, the video recording / playback apparatus 1 can suppress the return process from being performed on an acquired bad block that is unlikely to be returned to a normal block. Can be used more effectively.

(Seventh embodiment)
The video recording / playback apparatus 1 of the seventh embodiment is different from the video recording / playback apparatus 1 of the fourth embodiment in that a block state management unit 44f (not shown) is provided instead of the block state management unit 44c. The functional configuration of the video recording / playback apparatus 1 is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  The block state management unit 44f determines the block to be restored based on the resource usage status in the own device and the number of executions of the restoration process for the innate bad block. In this case, the setting information is stored as a first setting information table 422 shown in FIG. 8, a fourth setting information table 425 shown in FIG. 15, and a fifth setting information table 426 shown in FIG.

  FIG. 20 is a flowchart showing the flow of return processing in the seventh embodiment. First, the block state management unit 44f refers to the state information and determines whether there is a block managed as an acquired bad block (step S701). When there is no block managed as an acquired bad block (step S701-NO), the block state management unit 44f ends the return process. On the other hand, if there is a block managed as an acquired bad block (YES in step S701), the block state management unit 44f can process the return process in the next FI as in steps S502 and S503 in FIG. Is calculated (step S702).

  Subsequently, the block state management unit 44f determines whether there is a block whose return processing number is less than the processing number threshold among the blocks managed as acquired bad blocks (step S703). . If there is no block whose return processing count is less than the processing count threshold (step S703—NO), the block state management unit 44f ends the return processing. On the other hand, when there is a block whose return processing count is less than the processing count threshold value (step S703-YES), the block state management unit 44f uses as many blocks that can be processed as return target blocks. Select (step S704). Then, the block state management unit 44f performs test access (write or data erase) on the return target block (step S705). The block state management unit 44f determines whether or not the test access completion time is less than the completion time threshold (step S706).

  When the test access completion time is equal to or greater than the completion time threshold (step S706-NO), the block state management unit 44f updates the state information by incrementing the number of executions of the return process for the block by 1 (step S707). , The return process is terminated. On the other hand, if the test access completion time is less than the completion time threshold (step S706-YES), the block state management unit 44f determines that the return target block is a normal block and manages the block as a normal block (step S708). ).

  The video recording / playback apparatus 1 of the seventh embodiment configured as described above is a block state in which a restoration target block is determined based on the resource usage status in the own apparatus and the number of executions of restoration processing for the acquired bad block. A management unit 44f is provided. By including such a configuration, the video recording / playback apparatus 1 can more effectively utilize the resources of the own apparatus while suppressing the adverse effect of the return process on the recording or playback of the content.

(Eighth embodiment)
The video recording / playback apparatus 1 of the eighth embodiment differs from the video recording / playback apparatus 1 of the fourth embodiment in that a block state management unit 44g (not shown) is provided instead of the block state management unit 44c. The functional configuration of the video recording / playback apparatus 1 is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  The block state management unit 44g determines the access completion time when the block managed as the acquired bad block is changed from the normal block to the acquired bad block (hereinafter referred to as "abnormal time completion time"). Based on the above, the return target block is selected.

  FIG. 21 is a diagram illustrating a specific example of setting information according to the eighth embodiment. For example, the setting information in the eighth embodiment is stored as a sixth setting information table 427 shown in FIG. The sixth setting information table 427 has values of setting ID and abnormality completion time threshold. The setting ID is information for identifying a setting pattern of an abnormal completion time threshold set for writing and data erasing processing. The abnormal completion time threshold represents a threshold for abnormal completion time.

  FIG. 22 is a diagram illustrating a specific example of the state information in the eighth embodiment. For example, the state information in the eighth embodiment is stored as a state information table 411g shown in FIG. The status information table 411g is different from the status information table 411 in that the status information record has values of access type (write or data erasure) and abnormal completion time in addition to the block ID and block status. The abnormal completion time represents the access completion time when the block whose block state is “acquired bad block” is managed as an acquired bad block. The block state management unit 44g updates the state information table 411g according to access to the NAND memory by the content data input / output unit 31 and execution of block management processing.

  FIG. 23 is a flowchart showing the flow of return processing in the eighth embodiment. First, the block state management unit 44g refers to the state information and determines whether there is a block managed as an acquired bad block (step S801). When there is no block managed as an acquired bad block (step S801—NO), the block state management unit 44g ends the return process. On the other hand, when there is a block managed as an acquired bad block (step S801—YES), the block state management unit 44g sets the setting information used for the return process to be either “setting 1” or “setting 2”. It is determined whether the pattern is set (step S802).

  When the setting pattern is set to “setting 1” (step S802: “setting 1”), the block state management unit 44g causes the completion time when the acquired bad block is abnormal to be defined as “setting 1”. It is determined whether it is less than the completion time threshold (writing: “a ′”, data erasing: “A ′”) (step S803). When the abnormality completion time is equal to or greater than the abnormality completion time threshold (NO in step S803), the block state management unit 44g ends the return process. On the other hand, when the abnormal completion time is less than the abnormal completion time threshold (YES in step S803), the block state management unit 44g returns the acquired bad block whose abnormal completion time is less than the abnormal completion time threshold. A block is selected (step S804). The block state management unit 44g performs test access (write or data erase) on the return target block (step S805).

  The block state management unit 44g determines whether or not the test access completion time is less than the completion time threshold (write: “a”, erase: “A”) (step S806). When the completion time is equal to or greater than the completion time threshold (step S806—NO), the block state management unit 44g ends the return process. On the other hand, when the completion time is less than the completion time threshold (step S806: YES), the block state management unit 44g determines that the return target block is a normal block and manages the block as a normal block (step S807).

  On the other hand, when the setting pattern is set to “setting 2” in step S802 (step S802: “setting 2”), the block state management unit 44g determines that the acquired bad block completion time “ It is determined whether or not it is within the range (minimum value to maximum value) of the abnormality completion time threshold defined in setting 2 ”(write:“ b ′ ”, data erasure:“ B ′ ”) (step S808). . When the abnormal time completion time is not within the abnormal time completion time threshold (NO in step S808), the block state management unit 44g ends the return process. On the other hand, when the abnormal time completion time is within the abnormal time completion time threshold (step S808-YES), the block state management unit 44g acquires the acquired bad whose abnormal time completion time is within the abnormal time completion time threshold. The block is selected as a return target block (step S809). The block state management unit 44g performs test access to the return target block (step S805).

  The video recording / playback apparatus 1 according to the eighth embodiment configured as described above includes a block state management unit 44g that selects a return target block based on one or more preset thresholds for completion time in an abnormal state. According to such a configuration, the video recording / playback apparatus 1 can suppress a decrease in the use efficiency of the NAND memory by selecting a setting pattern according to the usage status of the own apparatus.

(Ninth embodiment)
The video recording / playback apparatus 1 of the ninth embodiment differs from the video recording / playback apparatus 1 of the fourth embodiment in that a block state management unit 44h (not shown) is provided instead of the block state management unit 44c. The functional configuration of the video recording / playback apparatus 1 is the same as the functional configuration of the video recording / playback apparatus 1 of the first embodiment shown in FIGS. 2, 3, and 4.

  The block state management unit 44h selects a return target block based on the number of data erasure processes performed in the past on the block managed as an acquired bad block.

  FIG. 24 is a diagram illustrating a specific example of the state information in the ninth embodiment. For example, the state information in the ninth embodiment is stored as a state information table 411h shown in FIG. The state information table 411h is different from the state information table 411 in that the state information record has a value of the number of data erasures in addition to the block ID and the block state. The data erasure count represents the number of data erasure processes performed on the block indicated by the block ID. The block state management unit 44h updates the state information table 411h according to the access to the NAND memory by the content data input / output unit 31 and the execution of the return process.

  FIG. 25 is a flowchart showing the flow of return processing in the ninth embodiment. First, the block state management unit 44h refers to the state information and determines whether there is a block managed as an acquired bad block (step S901). When there is no block managed as an acquired bad block (step S901-NO), the block state management unit 44h ends the return process. On the other hand, when there is a block managed as an acquired bad block (step S901-YES), the block state management unit 44h determines that the number of times of data erasure of the acquired bad block is a predetermined threshold (hereinafter referred to as “erasure count threshold”). It is determined whether or not (step S902). Note that the erase count threshold value is stored in advance as setting information in the ninth embodiment.

  When the number of data erasures is equal to or larger than the erasure number threshold (step S902-NO), the block state management unit 44h ends the return process. On the other hand, when the data erase count is less than the erase count threshold (step S902-YES), the block state management unit 44h selects the acquired bad block whose data erase count is less than the erase count threshold as the return target block (step S902). S903). The block state management unit 44h performs test access (write or erase) on the return target block (step S904).

  The block state management unit 44h determines whether or not the test access completion time is less than the completion time threshold (write: “a”, erase: “A”) (step S905). When the completion time is equal to or greater than the completion time threshold (step S905-NO), the block state management unit 44h ends the return process. On the other hand, when the completion time is less than the completion time threshold (step S905-YES), the block state management unit 44h determines that the return target block is a normal block and manages the block as a normal block (step S906).

  The video recording / playback apparatus 1 of the ninth embodiment configured as described above is a block that selects a return target block based on the number of data erasure processes performed on a block managed as an acquired bad block. A state management unit 44h is provided. By providing such a configuration, the video recording / playback apparatus 1 can target an acquired bad block that is more likely to be a normal block to be restored, and suppress a decrease in the use efficiency of the NAND memory. It becomes possible.

Hereinafter, modifications of the video recording / playback apparatus 1 of the embodiment will be described.
In block management processing in the video recording / playback apparatus 1, the number and setting method of setting patterns, a method of determining a normal block as an acquired bad block, a method of determining an acquired bad block as a normal block, and a method of selecting a restoration target block And the like may be realized by a combination of various setting methods and determination methods in the above embodiments.

  The determination of the normal block or the acquired bad block may be performed based on the processing other than the above-described writing or data erasure. For example, whether or not the access target block is an acquired bad block may be determined based on the completion time of the process of deleting or reading data from the NAND memory.

  Further, the block management process and the restoration process described above are not necessarily implemented in the video recording / playback apparatus 1 that records or plays back video, and any other processing apparatus can be used as long as the apparatus uses a NAND memory. May be implemented. Further, the block management process and the return process described above are not necessarily implemented in a processing apparatus specialized for a specific application, and may be implemented in a general-purpose storage device.

  According to at least one embodiment described above, a memory block other than the congenital bad block is changed to a normal block or a later block according to the processing time required until the write process or the erase process performed on the memory block is completed. By having a management unit that manages any of the natural bad blocks, it is possible to suppress a decrease in the use efficiency of the NAND memory.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 100 ... Broadcasting system, 1 ... Video recording / reproducing apparatus, 11 ... Main control part, 12 ... Recording output part, 13 ... Memory | storage part, 14 ... Reproducing part, 15 ... Transmission part, 2 ... Video acquisition apparatus, 3 ... Reproducing apparatus, DESCRIPTION OF SYMBOLS 4 ... Non-linear editing machine, 5 ... Operation terminal, 6 ... Monitor for image confirmation, 7 ... Broadcast equipment, 8 ... Recording medium, 10 ... Memory part, 101 ... Content data storage part, 102 ... Content management information storage part, 20 ... Memory controller, 21 ... input / output unit, 22 ... memory control unit, 30 ... content management unit, 31 ... content data input / output unit, 32 ... content control unit, 40 ... memory management unit, 41 ... memory information storage unit, 411, 411e, 411g, 411h ... status information table, 412 ... access information table, 413 ... excess information table, 414 ... cumulative information table, 42 ... setting information storage 421 ... Setting information table 422 ... First setting information table 423 ... Second setting information table 424 ... Third setting information table 425 ... Fourth setting information table 426 ... Fifth setting information table 427 ... First 6 setting information table, 43... Memory information acquisition unit, 44, 44a, 44b, 44c, 44d, 44e, 44f, 44g, 44h... Block state management unit

Claims (13)

The memory block of the storage medium is classified into a normal block, a congenital bad block that has been defective at the time of shipment from the factory, and an acquired bad block that has become defective at the time of use. A memory management device that manages only memory blocks classified as blocks,
A management unit that classifies memory blocks other than the congenital bad block as either the normal block or the acquired bad block according to the processing time required for the writing process or the erasing process performed on the memory block. ,
Memory management device. The management unit classifies the normal block as the congenital bad block when a processing time required for a writing process or an erasing process performed on the normal block exceeds a predetermined threshold time.
The memory management device according to claim 1. The management unit classifies the normal block as the congenital bad block when a processing time required for a writing process or an erasing process performed on the normal block continuously exceeds a predetermined threshold time a predetermined number of times. ,
The memory management device according to claim 1. The management unit converts the normal block into the innate bad block when the number of times that the processing time required for the writing process or the erasing process performed on the normal block exceeds a predetermined threshold time exceeds a predetermined number of times. Classify,
The memory management device according to any one of claims 1 to 3. In the writing process or the erasing process with respect to the normal block performed within a predetermined period, the management unit, when the ratio of the process exceeding the predetermined threshold time to the total process exceeds a predetermined ratio, Classify normal blocks into the congenital bad blocks;
The memory management device according to claim 1. In the writing process or the erasing process with respect to the normal block performed within a predetermined period, the management unit determines that the threshold value is greater than a predetermined ratio when the ratio of the processes whose processing time exceeds a predetermined threshold time exceeds the predetermined ratio Increase the time by a certain amount of time,
The memory management device according to claim 5. The management unit attempts a writing process or an erasing process on the acquired bad block, and normalizes the acquired bad block when a processing time required for the writing process or the erasing process becomes a predetermined threshold time or less. Perform return processing to classify into blocks,
The memory management device according to claim 1. The management unit determines an acquired bad block to be a target of the return process based on load information of the own device.
The memory management device according to claim 7. The management unit determines an acquired bad block to be a target of the return process based on the number of return processes executed in the past for each acquired bad block.
The memory management device according to claim 7 or 8. The management unit determines an acquired bad block as a target of the return process based on the number of erasure processes executed in the past for each acquired bad block.
The memory management device according to any one of claims 7 to 9. The management unit classifies a memory block other than the congenital bad block as either the normal block or the acquired bad block based on a threshold time selected from a plurality of the threshold times.
The memory management device according to claim 2. The memory blocks of the storage medium are classified into normal blocks, congenital bad blocks that are defective at the time of manufacture, and acquired bad blocks that are defective during use, and are classified as the normal blocks. A memory management method performed by a memory management device that manages only the memory blocks that have been used,
A management step of classifying a memory block other than the congenital bad block into either the normal block or the acquired bad block according to a processing time required for a writing process or an erasing process performed on the memory block; ,
Memory management method. A memory management device according to any one of claims 1 to 11,
A storage unit for storing video data for broadcasting;
A recording unit for acquiring the video data and storing it in the storage unit;
A reproduction unit for reading out and reproducing the video data from the storage unit;
With
The memory management device classifies memory blocks other than the congenital bad block in the storage unit as either the normal block or the acquired bad block, and recording or reproduction of the video data is performed with respect to the normal block. Managing the storage unit to be performed only
Video recording and playback device.