JPH09237474A - Tape cassette, digital data recorder and digital data reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the time required for the access operation on a magnetic tape at the time of recording/reproducing operation by loading/unloading at the option device areas which are provided for every partition. SOLUTION: When the data are read out after the partition #2 is recorded, the loading is made on the option device area of the partition #2 whereon the unloading is previously made, and next, the access is made to the position where a system log area of the partition #2 on the magnetic tape is ended. This access operation is executed in such a manner that the objective access position and the present position are compared by a system controller while referring the information of unloading position stored in the volume information of a MIC, which is a nonvolatile memory, and the area ID recorded on the magnetic tape. Then, the information of the system log area of the partition #2 stored in the MIC is read out by the system controller of a tape streamer drive and used for the management of reproducing operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette provided with a non-volatile memory, and a digital data recording device and a digital data reproducing device capable of recording and reproducing corresponding to such a tape cassette. To be done.

[0002]

2. Description of the Related Art A so-called tape streamer drive is known as a recording / reproducing apparatus capable of recording / reproducing digital data on a magnetic tape. Such a tape streamer drive can have an enormous recording capacity of, for example, several tens to several hundreds of gigabytes, depending on the tape length of a tape cassette as a medium. It is widely used for purposes such as backing up data recorded on media. Further, it is also suitable when used for storing image data having a large data size.

As the tape streamer drive as described above, for example, a tape cassette of 8 mm VTR is used as a recording medium, and a helical scan method by a rotary head is adopted to record / reproduce data. Proposed.

In the tape streamer drive using the 8 mm VTR tape cassette as described above, for example, an SCS is used as an input / output interface for recording / reproducing data.
I (Small Computer System Interface) is used. Then, at the time of recording, for example, data supplied from the host computer is input via the SCSI interface. This input data is assumed to be transmitted, for example, in units of a predetermined fixed-length data group, and the input data is subjected to compression processing by a predetermined method if necessary and is temporarily stored in the buffer memory. Then, the data stored in the buffer memory is supplied to the recording / reproducing system in units of fixed length called a predetermined group, and is recorded on the magnetic tape of the tape cassette by the rotary head. Further, during reproduction, the data on the magnetic tape is read by the rotary head and temporarily stored in the buffer memory. If the data from the buffer memory is compressed at the time of recording, it is expanded and transmitted to the host computer through the SCSI interface.

Further, the data recording area on the magnetic tape can be divided into partitions, and the tape streamer drive can independently reproduce and write data for each partition.

[0006]

In the data storage system comprising the tape streamer drive and the tape cassette as described above, in order to properly perform the recording / reproducing operation with respect to the magnetic tape of the tape cassette, for example, the tape streamer drive is used. As the management information and the like used for management of the recording / reproducing operation and the like, information related to various position information on the magnetic tape and usage history of the magnetic tape is required.

Therefore, it is considered to provide such a management information area at the head position on the magnetic tape or the head position of each partition. Then, on the tape streamer drive side, before executing the data recording or reproducing operation on the magnetic tape, the necessary management information is read by accessing the management information area, and subsequent recording / recording is performed based on this management information. Various processing operations are executed so that the reproduction operation is properly performed. After the data recording or reproducing operation is completed, the management information area is accessed again in order to rewrite the contents of the management information that need to be changed due to the recording / reproducing operation. By rewriting
It is prepared for the next recording / reproducing operation. After this,
The tape streamer drive unloads and ejects the tape cassette.

[0008]

However, when the recording / reproducing operation based on the management information is carried out as described above, the tape streamer drive does not perform magnetic recording at the start of the operation in any case of recording / reproducing. It is necessary to access the management information area at the head of the tape or the partition and access this management information area at the end to write / read information.
That is, loading and unloading cannot be performed at a position on the magnetic tape where the recording / reproducing of data is completed. In the case of a tape streamer drive, since it is necessary to physically send the magnetic tape for access, it is considerable to access the management information area at the beginning of the magnetic tape or the beginning of the partition at the end of recording / playback. It will take time. In particular, when data recording / reproduction is completed at a position physically far from the management information area on the magnetic tape, the amount of the magnetic tape to be sent increases accordingly, which takes extra time. . As described above, in the data storage system using the tape cassette as a medium, the time required for one recording / reproducing operation to be completed, that is, the time from when the magnetic tape is loaded to when the magnetic tape is finally unloaded is performed. The access operation requires a relatively long time. It is preferable that the time required for such a series of access operations be shortened as much as possible.

[0009]

In order to solve the above-mentioned problems, the present invention stores a magnetic tape on which digital data is recorded, and at least management information for managing recording / reproduction on the magnetic tape. As a possible tape cassette having a non-volatile memory, a data end area indicating the end of the data area and a loading / unloading area for loading / unloading can be recorded after the data area. Then, area IDs corresponding to the types of recording areas provided on the magnetic tape are set, and these recording area areas are recorded on the magnetic tape so as to include unique area IDs. In addition, the non-volatile memory is provided with an area for storing unloading position information indicating the position where the magnetic tape was last unloaded.

Digital data recording capable of recording digital data corresponding to a tape cassette provided with a magnetic tape and a non-volatile memory capable of storing management information for managing recording / reproduction with respect to the magnetic tape. As a device, following the recording of the data area, a data end area indicating the end of the data area and a loading / unloading area for performing loading / unloading can be recorded on the magnetic tape and It is decided to provide a recording control unit that enables loading / unloading in the unloading area. Further, the nonvolatile memory is provided with a memory write control unit capable of writing the unloading position information indicating the last unloaded position, and further, the unloading position information read from the nonvolatile memory and the magnetic Area ID corresponding to the type of recording area recorded on the tape
With reference to (1) and (2), an access control unit that can execute access control to a desired tape position after loading is provided.

Further, in response to a magnetic tape on which digital data is recorded and a tape cassette equipped with a non-volatile memory capable of storing management information for managing recording / reproduction on this magnetic tape, reproduction of digital data is possible. As a possible digital data reproducing device, the loading / unloading of the magnetic tape can be performed in the loading / unloading area for loading / unloading provided behind the data area on the magnetic tape. A reproduction control unit is provided, and further, a memory write control unit that can write the unloading position information to the nonvolatile memory is provided. Then, referring to the unloading position information read from the non-volatile memory and the area ID corresponding to the type of the recording area recorded on the magnetic tape, the access control to the required tape position after loading is executed. We decided to provide an access control unit that can do this.

According to the above arrangement, it is possible to load / unload the magnetic tape in the loading / unloading area provided behind the data writing end area on the magnetic tape. Further, by referring to the unloading position information read from the non-volatile memory and the area ID on the magnetic tape, the position where the recording / reproducing of data should be started immediately is accessed to record / reproduce the data. It becomes possible to do it. At the same time, an area of management information for recording / reproducing of the magnetic tape is provided in the nonvolatile memory of the tape cassette, and data is rewritten in this area, so that the end of recording / reproducing and There is no need to access a predetermined management information area on the magnetic tape at the start.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. Here, various inventions of a tape cassette provided with a non-volatile memory and a tape streamer drive capable of recording / reproducing images of digital data corresponding to the tape cassette with the memory have been proposed by the present applicant. However, the present invention applies the data storage system including the tape cassette with the memory and the tape streamer drive to the present invention. In addition, the non-volatile memory provided in the tape cassette will be described later in the MIC.
(Memory In Cassette)

The following description of the embodiments will be made in the following order. 1. Structure of tape cassette 2. Configuration of recording / reproducing apparatus 3. Structure of data recorded on magnetic tape 4. ID area 5. Data structure of MIC (a) Data structure of entire MIC (b) System log area 6. Access example of recording / reproducing apparatus (a) Access example without MIC (b) Access example with MIC (1) (c) Access example with MIC (2) (d) MIC Access example (3)

1. Configuration of Tape Cassette First, a tape cassette corresponding to the tape streamer drive of the present embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 conceptually shows the internal structure of the tape cassette, and reels 2A and 2B are provided inside the tape cassette 1 shown in this figure, and a magnetic tape having a tape width of 8 mm is provided between the reels 2A and 2B. 3 is wound. The tape cassette 1 is provided with a non-volatile memory MIC4, and a power supply terminal 5A, a data input terminal 5B, a clock input terminal 5C, a ground terminal 5D, etc. are derived from the module of the MIC4. As will be described later, the MIC 4 stores the manufacturing date and manufacturing location of each tape cassette, the thickness and length of the tape, the material, the information related to the usage history of the recorded data of each partition, the user information and the like. To be done. In this specification, various information stored in the MIC 4 and a system log area (System
Since the information of the Log Area) is mainly used for various management of recording / reproduction with respect to the magnetic tape 3, these are collectively referred to as “management information”.

FIG. 3 shows an example of the appearance of the tape cassette 1. The entire housing includes an upper case 6, a lower case 7,
And a guard panel 8 and is basically the same in structure as a tape cassette used for a normal 8 mm VTR. The label surface 9 on the side surface of the tape cassette 1 is provided with terminal pins 10A, 10B, 10C, and 10D. The power supply terminal 5A, the data input terminal 5B, the clock input terminal 5C, and the ground described in FIG. Terminal 5D
And are connected to each. That is, in the present embodiment, the tape cassette 1 includes the tape streamer drive described below and the terminal pins 10A and 10A.
It is assumed that data signals and the like are mutually transmitted through physical contact via B, 10C, and 10D.

2. Configuration of Recording / Reproducing Device Next, the configuration of the tape streamer drive of the present embodiment will be described with reference to FIG. This tape streamer drive uses a tape cassette with a tape width of 8 mm,
Recording on magnetic tape by helical scan method /
It is supposed to play. In this figure, the rotary drum 11 is provided with, for example, two recording heads 12A and 12B and two reproducing heads 13A and 13B. The recording heads 12A and 12B have a structure in which two gaps having different azimuth angles are located close to each other. Similarly, the reproducing heads 13A and 13B also have a structure in which two gaps having different azimuth angles are arranged extremely close to each other.

The rotating drum 11 is rotated by the drum motor 11, and the magnetic tape 3 pulled out from the tape cassette 1 is wound around it. The magnetic tape 3
Are fed by a capstan motor and a pinch roller (not shown). The drum motor 14 is driven by the control of the mechanical controller 17. The mechanical controller 17 performs servo control and tracking control of the drum motor 14, and is bidirectionally connected to a system controller 15 that executes control processing of the entire system.

In this tape streamer drive, a SCSI interface 20 is used for data input / output. For example, when recording data, a fixed-length record (reco) to be described later is sent from the host computer 25.
Data is sequentially input via the SCSI interface 20 in a transmission data unit called rd) and supplied to the compression / expansion circuit 21. In such a tape streamer drive system, there is also a mode in which data is transmitted from the host computer 25 in units of variable-length data sets, but the description thereof is omitted here.

In the compression / expansion circuit 21, if necessary, the input data is compressed by a predetermined method. As an example of the compression method, for example, LZ
If a compression method using codes is adopted, in this method, a special code is assigned to a character string processed in the past and stored in the form of a dictionary. Then, the character string input subsequently is compared with the contents of the dictionary, and if the character string of the input data matches the code of the dictionary, this character string data is replaced with the code of the dictionary. Data of the input character string that does not match the dictionary is sequentially given a new code and registered in the dictionary. In this way, the data of the input character string is registered in the dictionary, and the character string data is replaced with the code of the dictionary, whereby the data compression is performed.

The output of the compression / expansion circuit 21 is supplied to the buffer controller 22. In the buffer controller 22, the compression / expansion circuit 2 is controlled by the control operation.
1 is temporarily stored in the buffer memory 23. Under the control of the buffer controller 22, the data stored in the buffer memory 23 is finally handled as a fixed-length unit corresponding to 40 tracks of a magnetic tape called a group as described later. This data is supplied to the ECC / modulation / demodulation circuit 18.

In the ECC / modulation / demodulation circuit 18, an error correction code is added to the input data, and the input data is modulated so as to be suitable for magnetic recording and supplied to the RF amplifier 19. The recording signal amplified by the RF amplifier 19 is supplied to the recording heads 12A and 12B so that data is recorded on the magnetic tape 3.

The data reproducing operation will be briefly described. The recorded data on the magnetic tape 3 is reproduced by the reproducing head 13.
It is read out as an RF reproduction signal by A and 13B, and its reproduction output is supplied to the ECC / modulation / demodulation circuit 18 via the RF amplifier 19, and after undergoing demodulation processing, error correction processing is performed. The demodulated output of the ECC / modulation / demodulation circuit 18 is temporarily stored in the buffer memory under the control of the buffer controller 22, and is supplied from this to the compression / decompression circuit 21. In the compression / expansion circuit 21, the compression / expansion circuit 2 is used for recording based on the judgment of the system controller 15.
If the data is compressed by 1, the data decompression process is performed here, and if it is the non-compressed data, the data decompression process is not performed and the data is directly passed and output. The output data of the compression / expansion circuit 21 is output to the host computer 25 as reproduction data via the SCSI interface 20.

Further, in this figure, the MIC 4 is shown together with the magnetic tape 3 of the tape cassette. This MIC4
When the tape cassette body is loaded in the tape streamer drive, the data is connected to the system controller 15 via the terminal pins shown in FIG.

Information is mutually transmitted between the MIC 4 and the external host computer 25 using SCSI commands. Therefore, it is not necessary to provide a dedicated line between the MIC 4 and the host computer 25,
As a result, the data exchange between the tape cassette and the host computer 25 can be established only by the SCSI interface.

3. Structure of Data Recorded on Magnetic Tape Next, a data format applied to the data storage system including the tape streamer drive and the tape cassette described above will be schematically described. FIG.
Indicates the structure of data recorded on the magnetic tape 3. In FIG. 4A, one magnetic tape 3 is schematically shown. In the present embodiment, as shown in FIG. 4B, one magnetic tape 3 is divided into partitions (Partition).
The number of partitions can be set and managed up to 256 in the system of the present embodiment. Further, each partition shown in this figure is managed by being given a partition number as described as partitions # 0, # 1, # 2, # 3 ,. Therefore, in the present embodiment, it is possible to independently record / reproduce data for each partition. For example, the data recording unit in one partition shown in FIG. Group (Group) shown in 4 (c)
It is possible to divide the unit into fixed-length units, which are referred to as "units". In this case, one group has 20 frames (Fr
corresponding to the data amount of (ame), as shown in FIG. 4D, one frame is formed by two tracks. In this case, two tracks forming one frame are plus azimuth and minus azimuth tracks adjacent to each other. Therefore, one group is formed by 40 tracks.

The one partition shown in FIGS. 4A and 4B is formed by the data structure shown in FIG. In addition, in this figure, it is assumed that one partition is formed for the entire tape length. Further, in this embodiment, the tape cassette is provided with MI.
By providing C4 and adopting the data structure on the magnetic tape described in detail later, it is possible to load / unload in the middle of the tape, but here, it is also compatible with tape cassettes without MIC. It is meant to indicate the possible generic formats.

In the case of FIG. 5, the leader tape is physically located at the beginning with respect to the first portion of the magnetic tape, and the device area which becomes the area for loading / unloading the tape cassette next is formed. It is provided. The head of this device area is the head position PBOT (Phisycal Bigining of Tape) of the physical tape. Following the device area, a system log area for storing tape usage history information and the like is provided, and a data area is provided thereafter. The beginning of the system log area is the logical tape start position LBOT (Logical Bigi
ning of Tape). In this data area, a vendor group in which information about a vendor that creates and supplies data is first provided is provided, and subsequently, the groups actually shown in FIG. 4C are shown as groups 1 to n here. As described above, a plurality of layers are continuously formed. Then, following the last group n, an EOD (End of D) indicating the end of the data area of the partition is displayed.
area is provided. Then, the end of the EOD is set as a logical tape end position LEOT (Logical End of Tape). PEOT (Phisycal End of Tape) indicates the end position of the physical tape or the physical end position of the partition.

The structure of data for one track shown in FIG. 4D is shown in FIGS. 6A and 6B. FIG. 6A shows a data structure in block units. 1 block is 1 byte SYN
The C data area A1 is followed by a 6-byte ID area A2 used for searching and the like, a 2-byte error correction parity area A3 for ID data, and a 64-byte data area A4. The data for one track shown in FIG. 6B is formed by all 471 blocks, and one track is provided with margin areas A11 and A17 for four blocks at both ends as shown in the figure. ATF areas A12 and A16 for tracking control are provided behind and in front of the margin A17. ATF area A for the middle of one track
14 is provided. These ATF areas A12 and A1
Areas for 5 blocks are provided as 4 and A16.
Then, between the ATF areas A12 and A14 and the AT
Data areas A13 and A15 for 224 blocks are provided between the F areas A14 and A16, respectively. Therefore, the total data area (A13 and A15) in one track is 224 × 2 = 4 out of all 471 blocks.
It will occupy 88 blocks. The tracks are physically recorded on the magnetic tape 3 as shown in FIG. 6C, and as described above, 40 tracks (= 2).
One group will be formed in 0 frame).

4. ID Area Next, regarding the ID area A2 shown in FIG.
This will be described with reference to FIGS. FIG. 7 shows the data structure of the ID area A2. The ID area A2 is a 9-bit physical block address (Physi
cal Block Address) A21, followed by a 39-bit ID Information Area
It consists of the area of A22.

As described above, since the total data area (A13 and A15) in one track consists of 448 blocks, the number of physical block addresses A21 included in these total data areas is also 448. The physical block address A21 of these 448 is, for example, the physical block address A21 located at the head of one track as schematically shown in FIG.
Address values are given in increments of 0 to 447 in decimal notation in order from 21. As a result, the ID information area A included in the data area in one track, for example, by the recording / reproducing apparatus side
22 information can be handled properly. Here, as the data size of the ID information area A22 included in the data area in one track,
39 (Bit) x 448 (Block) = 17,472 (Bit) =
It becomes 2,184 bytes as calculated by 2,184 (Byte).

FIG. 9 shows the types of ID area information stored in the ID information area A22 shown in FIG. 7, and each ID area information shown in this figure is included in the data area on one track. A total of 2,184 bytes of ID information areas A22, A22 ...
.. will be stored in such a manner that they are applied to the area of. Further, in consideration of enabling reliable reading of the ID area information by the tape streamer drive, the same type of ID area information is recorded a plurality of times for each track according to a predetermined rule.

In FIG. 9, the row format ID
(Raw Format ID: 16bit) indicates the type of basic format relating to the magnetic tape. In the case of the present embodiment, for example, track pitch, data size of one frame, number of blocks included in one track, one block Data size, tape length, tape thickness, tape material, etc. are shown. Logical format ID (Logical Fo
rmat ID: 8bit) indicates the type of recording format actually used. Logical frame ID (Logical
Frame ID: 8bit is the last frame ID (La
st Frame ID: 1bit), ECC frame ID (ECC Frame I
D: 1bit) and logical frame number (Logical Fram
e Number: 6bit). The last frame ID indicates whether or not the current frame including the ID area is the last frame in the group, and the ECC frame ID
Indicates that the recorded data in the data area of the current frame is ECC
Indicates whether or not it is (error correction code). Also, as described above, one group consists of 20 frames, but the logical frame number indicates the number of the frame in the current group. Partition ID
(Partition ID: 16bit) indicates the partition number of the partition including the current frame. Area ID
(Area ID: 4bit) indicates which area the frame belongs to. Data ID (Data ID: 4b
It) indicates the type of data processing format based on the recording format, and N-Position (N-Position: 4bit)
Information on data corresponding to the multiple recording mode is defined in N-Repeats (4 bits). The group count (Group Count: 24 bits) indicates the total number of groups up to the group including the frame in the current partition. Also, the file mark count (File-M
(ark Count: 32 bits) indicates the total number of file marks included in the current partition from the start position to the current group. The file mark is information indicating a delimiter of a data file in one partition. Save Set Mark Coun
(t: 32bit) indicates the total number of file marks contained in the current partition from the start position to the current group. The save set mark is information indicating a data save position delimiter within one partition. The record count (Record Count: 32bit) indicates the total number of records included in the current partition from the start position to the current group. Absolute Frame Count (24bit)
Indicates the total number of frames included in the current partition from the start position to the current group. In addition, it is undefined (Res
erved) area is provided. Note that the definition of the ID area information and the number of bits given to each ID area information shown in this figure are examples, and may be changed according to actual usage conditions.

Here, of the various ID area information shown in FIG. 9, the area ID (Are
a ID) is explained. FIG. 10 shows the definition contents of the area ID. In this case, the bit number (3-2-1) is set for each of the 4 bits forming the area ID.
-0) is attached. Then, the bit number (3-2
As shown in the figure, when each value of (-1-0) is [0000], it is defined as a device area (Device Area), and when it is [0001], it is a reference area. (Reference Area), and [001
0], the system log area (System
Log Area). [0011] is undefined (Reserve
d). [0100] is a data area, and [0101] is an EOD area (EO).
D Area), [0110] is undefined, and [0111]
Is defined as an optional device area (Option Device Area) for loading / unloading the magnetic tape 3 in addition to the essential device areas shown in FIG. This optional device area will be described later. In this figure, the bit number (3
The numbers shown in parentheses in each column where the bit value of (-2-1-0) is shown indicate each bit value in decimal notation.

Here, referring to FIG. 11, the EOD area (see FIG.
An example of the ID area information to be written in the ID information area A22 (see the reference) will be shown. FIG. 11 shows the contents of the ID area information stored in the ID information area A22 in one EOD area, and one vertical line delimiter is used.
It is set in frame units. In addition, the numerical values shown in this figure are shown in decimal notation. The EOD area is defined to be recorded on the magnetic tape 3 as an area including, for example, approximately 300 frames. In this figure, the absolute frame count in the start frame of the EOD area is set to "654", and the EOD
The absolute frame count of the last frame of the area is set to "954". This indicates that this EOD area is formed by a total of 301 frames located at positions 654 to 954 in the current partition. Further, as described above with reference to FIG. 10, when the 4 bits of the area ID are [1, 1, 0, 1], that is, decimal [5], it is an EOD area. However, according to this in FIG. 11, the area ID in each frame of the EOD area is
All are given in decimal [5], numbered 654-95
This indicates that all the fourth frames belong to the EOD area.

The values given to the other ID area information will differ depending on the actual tape format and the history of recording / reproducing operations, and therefore description thereof will be omitted and here, for each frame. By adding “0” as a value to, the description of specific numerical values is omitted. However, actually, when a value of "0" is given to each ID area information, a predetermined information content corresponding to the value of "0" is defined. As an example, when the value of the format ID is actually “0”, it indicates that the frame is data recorded based on “SDX1Format”.

5. Data Structure of MIC (a) Data Structure of Entire MIC Next, the data structure of the MIC 4 provided in the tape cassette 1 will be described. FIG. 12 shows the structure of data stored in the MIC 4. The capacity of the MIC4 is, for example, 2 megabytes, and fields F1 to F6 are set in this area as shown in the figure.
In these fields F1 to F6, the field F1
Is a MIC header, and various information at the time of manufacturing the tape cassette, tape information at the time of initialization, information for each partition, and the like are written therein. The field F2 is for absolute volume map (Absolut
e Volume Map), for example, absolute position information regarding data recorded on one magnetic tape is stored. The field F3 is used as volume information, and various usage history information regarding one magnetic tape is stored. The information stored in these areas is used for recording / playback control and the like in the tape streamer drive. In the present embodiment, an area for storing "unloading position information" as information indicating the last unloading position is provided for this volume information as shown in () in the figure.

Field F4 is a user volume note
(User Volume Note), information provided by the user (vendor, etc.) regarding the tape cassette itself is stored, and if necessary, it is supplied to the external host computer 25 and can be used for necessary processing control. it can. Field F5 contains partition information (P
artitions Information), which stores various information related to the usage history of the magnetic tape for each partition written to the magnetic tape, and is used by the tape streamer drive as information for managing its own recording / reproducing operation. To be done. This partition information is stored in the system log area F5a as shown in the figure.
Is formed by the region of. System log area F5a
Is created for each partition actually recorded on the magnetic tape, the number of tables in the system log area F5a corresponds to the number of partitions provided on the magnetic tape. Further, in the present embodiment, the system log area area on the magnetic tape shown in FIG. 6 is formed so that information having the same contents as the system log area area F5a in this MIC can be written. . The data structure in the system log area F5a will be described later.

The field F6 is a user partition note, and stores various information such as comments writable by the user for each partition. The user partition note in the field F6 is a user data area F6a (Us) created corresponding to each partition recorded on the magnetic tape.
er Data for every Partition).

(B) System Log Area Next, the system log area F5a will be described. The system log area F5a forms the area of the partition information (field F5) as described above, and is formed corresponding to each partition recorded on the magnetic tape 3. In this case, if there are multiple partitions recorded on the magnetic tape,
The system log area F5a will store information about partitions, but if there is one partition, the information in the system log area F5a will be about the entire magnetic tape. The following description is based on the former case where the system log area F5a stores information about partitions.

The data structure of one system log area F5a is defined, for example, as shown in FIG. 12, and in this case, it is formed by fields F101 to F115. In these fields F101 to F115,
First, the field F101 is an area of the Previous Groups written.
In this area, information on the number of groups in the partition physically recorded on the magnetic tape, starting from the time when the system log area F5a was last updated, is shown. The field F102 is a total group written area, and indicates the total number of groups recorded so far in the partition. This value is added up until the tape cassette reaches the end of its life and cannot be used or is discarded. If the data is being recorded on the magnetic tape 3 by the tape streamer drive, for example, the pre-group group return and the total group return are updated by the current recording operation by the processing of the system controller 15 of the tape streamer drive. The value of the area is incremented according to the number of groups recorded in.

The field F103 is used as a previous group read, and indicates the number of groups physically read from the time when the system log area F5a was last updated. . A field F104 is a total group read (Total Groups read) and indicates a value obtained by accumulating the number of groups read from the partition so far.

The field F105 is an area of total rewritten frames. By the way, in the tape streamer drive of the present embodiment, the reproducing heads 13A and 13B are the recording heads 12.
The rotary head 11 is provided so as to have a positional relationship that leads the A and 12B by a predetermined number of tracks. During recording, the two recording heads 1
Recording is performed in units of frames (2 tracks) on the magnetic tape by 2A and 12B.
In A and 13B, data is read from the frame written on the magnetic tape by the recording heads 12A and 12B. This operation is performed by READ-AFTER-WRITE (hereinafter abbreviated as RAW
Is described). The error rate of the frame data read by the RAW is detected by the system controller 15, and when it is detected that an error has occurred, the frame data in which the error has occurred is rewritten. The recording system is controlled. The total relit frame of the field F105 indicates a value obtained by integrating the number of frames for which data rewriting is requested based on the RAW in the partition.

The field F106 has a total of 3rdE.
It is used as a CC count (Total 3rd ECC count) area. In the tape streamer drive system of the present embodiment, the data read from the magnetic tape 3 is C
Although the error correction is performed by the parity of 1, C2, C3, the C3 parity is used when the data cannot be recovered only by the C1, C2 parity.
The total 3rd ECC count indicates a value obtained by accumulating the number of groups in which the error correction is performed using the C3 parity in the partition. Field F1
Reference numeral 07 denotes a load count area, which indicates a value obtained by integrating the number of times the tape has been loaded. A field F108 is an access count area and indicates the number of times the tape streamer drive has accessed the partition. Field F10
9 is the previous rewritt frame
The RAW described above indicates the number of frames in the partition where the data rewrite request is made, counting from the time when the system log area F5a was last updated. Be done. The field F110 shows the Pre-Bead 3rd ECC count (P
revious 3rd ECC count), counting from the time when the system log area F5a was last updated, C3
The number of groups in which error correction is performed using parity is shown.

The field F111 is used as an ID map number and stores information on the definition number of the search index, but in the case of the present embodiment, it is always set to "0" as a value. There is. Field F1
The valid maximum absolute frame count (Valid Max. Absolute frame count) of 12 indicates the frame count information up to the last frame that is valid in the partition, and the maximum absolute frame count (Max. Ab
The solute frame count) area shows information on the last frame count of the partition. Also, update replace count (Upd
The “ate Replace count” area shows information obtained by integrating the number of times the data is rewritten to the magnetic tape in the partition by the update. In the flag area of the last field F115, for example, a flag indicating write permission / prohibition for the partition, read permission / prohibition, and rewriting permission / prohibition of data based on RAW at the time of recording, a tape streamer drive Data such as a flag indicating that some processing is currently being performed on the partition is stored.

By the way, as described above with reference to FIG.
A system log area is provided at the beginning of each partition on the magnetic tape 3. In the system log area provided on the magnetic tape 3, it is possible to record the same information content as the system log area F5a of the MIC 4 shown in FIG. 12 with the same data structure. That is, in the data storage system of this embodiment, the area in which the system log information can be stored is M
It will be provided for both the IC 4 and the magnetic tape 3.

6 Example of access to recording / reproducing apparatus (a) Example of access without MIC As the data storage system of the present embodiment described above, the magnetic tape at the time of recording / reproducing by the tape streamer drive shown in FIG. An example of the access operation to the will be described with reference to FIGS. By the way, the data storage system of the present embodiment is
Although it has been described as being compatible with a tape cassette provided with the MIC4, it is provided with versatility so that recording / reproducing operations can be performed corresponding to a tape cassette not provided with the MIC4. . Therefore, first, with reference to FIG. 17, an example of an access operation of the tape streamer drive in the case of supporting a tape cassette in which the MIC 4 is not provided will be described.

FIG. 17 schematically shows the data recorded on the magnetic tape 3. In this case, a device area (Device Are) provided at the beginning of the magnetic tape 3 is shown.
a: See Fig. 5), followed by partitions # 0, # 1, #
2 is shown. According to this figure, the tape streamer drive in the case of newly recording the partition # 2 from the state where the partitions # 0 and # 1 are already recorded on the magnetic tape 3 of the tape cassette not provided with the MIC4 is shown. The access operation will be described. In this figure, the numbers in parentheses indicate the order of access operations of the tape streamer drive.

In the case of a tape cassette having no MIC 4, the loading and unloading of the magnetic tape 3 is always performed in the device area at the head of the magnetic tape. Therefore, as the operation of the tape streamer drive for recording the partition # 2, first, the loading (1) of the magnetic tape 3 is performed in the device area, and then the end position of the partition # 1 is searched while feeding the tape at a high speed. Yes (2). And
From the frame next to the end position of partition # 1, additional writing of partition # 2 will be performed. First, create a system log area for partition # 2 (3) . In addition,
At this time, default content data is recorded in the system log area. The data contents and data structure of the system log area are the same as the MIC described in FIG.
4 is the same as the system log area F5a.

Next, when the writing in the system log area is completed, the data supplied from the host computer 25 side is written next (4). As a result, a data area (Data Area) following the system log area is formed. When the data writing is completed, the EOD area is written (5). By writing this EOD area, it is shown that there is no valid data area in the subsequent magnetic tape 3.

As described above, the system log area, data area, and EOD area of partition # 2 are sequentially recorded, and the area of partition # 2 is physically provided. At this time, the area ID of the ID information area recorded in each of these areas
(Area ID: See Fig. 9 and Fig. 10), the system log area, data area,
It will be shown to be the EOD area.

When the writing of the EOD area is completed, the tape streamer drive searches the head of the system log area of the partition # 2 (6). Then, in the system log area of partition # 2, writing of the above data area (4) and EOD
The data content of the field to be changed corresponding to the writing (5) of the area is updated (7).

By the way, when recording / reproducing is performed for a tape cassette in which the MIC 4 is not provided, for example, in the system log area of the first partition # 0, not the history information of only the partition # 0 but the magnetic information is recorded. The data of each field F101 to F115 is handled so that the usage history information of all partitions recorded on the tape can be managed. Therefore, after the data in the system log area of partition # 2 has been updated, the beginning of the system log area of partition # 0 is accessed from the end position of this system log area (8), and then After updating the data of the required field in the system log area of partition # 0 (9), the head device area of the magnetic tape 3 is accessed (10), and unloading is performed here (11). To be done. Therefore, access order (7)
The operation of updating the data in the system log area of partition # 2 can be treated as an option and can be omitted. In this case, after writing the EOD area, the head of the system log area of the partition # 0 is accessed ((5) → (8)).

Although an access operation example at the time of reproduction corresponding to a tape cassette not provided with the MIC4 is not shown, it is based on the access operation at the time of recording shown in FIG. That is, after loading the device area at the head of the magnetic tape, the system log area of the partition # 0 is accessed once to read the system log information. Next, the system log area of the required partition is accessed to read the system log information, and then the data area of the current partition is accessed to read the data. When this is completed, the system log area of the current partition is updated, then the system log area of partition # 0 is accessed again to update the system log information, and unloading is performed in the device area. Note that the format to update the system log area for each partition is an option. If this format is not used, access to access the system log area of the required partition to read / update system log information is made. The operation is omitted.

(B) Example of access when MIC is present (1) In the access operation at the time of recording corresponding to the tape cassette in which the MIC shown in FIG. 17 is not provided, the system log area on the magnetic tape 3 is updated, Loading / unloading in the first device area of the magnetic tape 3 is essential. Therefore, the number of access actions and the total amount of tape feeding increase accordingly, and thus the access operation during one recording / reproducing operation takes time.

On the other hand, as a feature of the present embodiment, when recording / reproducing is performed corresponding to the tape cassette 1 equipped with the MIC 4, data recording / reproducing is performed as described below. It is possible to perform loading / unloading at an intermediate position on the magnetic tape, which has been completed, and it is also possible to eliminate the need to update data in the system log area on the magnetic tape.

FIG. 13 shows an example of access operation of the tape streamer drive at the time of recording and reading of data when the MIC 4 is provided in the tape cassette 1. The same parts as those in FIG. 17 are designated by the same reference numerals and the description thereof will be omitted. First, as the recording operation shown in this figure, partitions # 0 and # 1 are recorded on the magnetic tape.
An example of access operation when a partition # 2 is newly written from the state in which is recorded will be described.

In this case, it is assumed that the last operation of the tape streamer drive for the magnetic tape 3 was the recording or reproducing operation for the partition # 1. In this case, it is assumed that the tape streamer drive is unloading in the option device area of the partition # 1 on the magnetic tape 3 at the end of the recording or reproducing operation on the partition # 1. To be done. Therefore, loading (1), which is the first operation for newly writing the partition # 2, is performed in the option device area of the partition # 1.

The optional device area is a device area provided for each partition, that is, an area provided for loading / unloading in units of partitions. For example, a partition is recorded corresponding to a tape cassette with MIC. In case,
Writing will be performed by the tape streamer drive side as described later.

When loading is performed in the option device area of partition # 1 as described above, the frame next to the end position of partition # 1 (in this case, the end position of the option device area of partition # 1). Therefore, as a write operation of the partition # 2, first, a system log area for the partition # 2 is created (2). When the writing of the system log area is completed, the data is written to form the data area (3), and when this is completed, the EOD area is written (4).

Then, when recording is performed on the tape cassette with the MIC as in the case of FIG. 13, the above E
When the writing of the OD area is completed, the writing of the option device area of the partition # 2 is subsequently performed (5). In this optional device area, for example, the partition ID of the ID area A2
"2 (decimal system)" is given as (see FIG. 9) and the area ID described in FIG. 10 is "7 (decimal system)". It is shown to be an area. And
When the writing of the option device area is completed, the magnetic tape 3 is returned to the almost intermediate position of the area of the option device area in which the writing has just been performed, and the unloading is performed here (6). At this time, in the MIC 4 of the tape cassette 1, a system log area F5a corresponding to the partition # 2 corresponding to the progress of the recording operation so far is newly created and stored in a predetermined area, and another MIC 4 is also stored. If there is an area that needs rewriting in the data area, the data will be rewritten. Therefore, in this case, the system log area on the magnetic tape 3 is not rewritten. At this time, the unloading position information is MIC.
Volume information of 4 (field F3)
Stored in. The information content may be, for example, data indicating the system log area of the partition # 2, but may be absolute position information on the magnetic tape of the unloading position.

Here, the processing operation of the system controller 15 of the tape streamer drive for additionally recording the partition as described above will be described with reference to the flowchart of FIG. In this routine, for example, when a request for adding a new partition #n is received from the host computer 25 in step S101, the system controller 15 proceeds to step S102, and from the tape cassette loaded in the tape streamer drive. Load magnetic tape. Then, in step F103, as the additional writing process of the partition #n, the system log area is first created from the frame next to the end position of the partition # (n-1), and then the data writing is executed to form the data area. (Step S104),
After the data area is written, the EOD area is written (step S105). When the writing of the EOD is completed, the system controller 15
The system log information corresponding to the partition #n newly provided by the processing operation of steps S102 to S105 is stored in the MIC of the tape cassette (step S106). Then, the next step S1
At 07, the option device area following the EOD area provided at the previous step S105 is written, and at the next step S108, the magnetic tape is sent to an almost intermediate position of the option device area for unloading. . In this case, the tape cassette is ejected in the next step S109.

After the partition # 2 is recorded as described above with reference to FIG. 13, for example, when the data of this partition # 2 is read, the access shown in the lower row of FIG. 13 is similarly performed. It will be done in order. In this case, as the first operation, loading is performed in the option device area of the partition # 2 that was unloaded during the recording of the previous partition # 2 (1), and then the partition # 2 on the magnetic tape 3 is loaded. Access the end position of the system log area (2). This access operation is performed by referring to the unloading position information stored in the volume information of the MIC 4 and the area ID recorded on the magnetic tape, and the system controller 15 compares the target access position with the current position. Will be realized.
Then, the data area following the system log area is accessed to read the recorded data (3). Therefore, the system log area on the magnetic tape is not accessed, but in this case, the MIC
The system controller 15 of the tape streamer drive reads out the information of the system log area F5a of the partition # 2 stored in the disk and uses it for management of the reproduction operation. Then, as the read operation of the recording data, when the read is performed up to the end position of the EOD area following the data area, the magnetic tape 3 is read up to almost the intermediate position of the option device area of the partition # 2.
And unloading is performed here (4).
At this time, the unloading position information to be stored in the volume information of the MIC 4 is updated if necessary.

Here, an example of access to the magnetic tape corresponding to the case where the MIC 4 is not provided in the tape cassette 1 described above with reference to FIG. 17 and the M described in FIG.
Comparing with the access example corresponding to the case where the IC4 is provided, in the case of FIG. 17, since loading / unloading is performed in the device area at the head of the magnetic tape, the magnetic tape is read. At the end of recording / playback, it was always necessary to access the device area at the beginning of the magnetic tape. Therefore, record /
It will take time to complete the playback. Especially when the magnetic tape is supposed to be near the end at the end of data recording / reproduction, it takes a lot of time to access the device area. Further, in this case, it is necessary to access the system log area on the magnetic tape and read the information when recording / reproducing data.

On the other hand, in the case of FIG. 13, by providing an optional device area for each partition, loading / unloading in this area is possible. That is, it is possible to perform loading / unloading at an intermediate position of the magnetic tape 3, which is considered to have completed recording / reproduction. As a result, FIG.
It is not necessary to access the device area at the beginning of the magnetic tape at the end of data recording / playback or access to a recording / playback position physically distant from this device area as in the case of, and the access time is reduced accordingly. become. Further, by writing the system log information to the MIC4, it is not necessary to access the system log area on the magnetic tape to write the data, which also reduces the number of access actions. Will be shortened. Here, in the case of FIG. 13, the system log area provided in each partition is not used for management of the actual recording / reproducing operation.
When the information in the MIC cannot be used due to a failure of the memory card, it is possible to record / reproduce data from the head of the magnetic tape by the access operation according to FIG.

(C) Example of access when MIC is present (2) Next, as an example of access to a tape streamer drive corresponding to a tape cassette with an MIC, data in one partition already recorded on a magnetic tape is recorded. A case of rewriting (updating) will be described with reference to FIG. FIG. 15 shows an access example when rewriting data in the partition #n. In this case, it is assumed that the previous operation of the tape streamer drive for the tape cassette was the recording or reproduction of partition #n, and therefore the first access operation is the optional device of partition #n as shown in the figure. Loading will be done in the area. After that, the end position of the system log area of the partition #n is accessed by referring to the unloading position information stored in the MIC 4 and the area ID recorded on the magnetic tape (2). If the previous operation of the tape streamer drive for the tape cassette is recording or reproducing of partition # (n-1),
The first loading is performed in the option device area of partition # 1 to access the end position of the system log area of partition #n. At this time, the system controller 15 of the tape streamer drive is supposed to read and store data from the MIC 4 of the tape cassette.

Thereafter, new data is written from the frame next to the end position of the system log area of partition #n by overwriting the previously recorded data, whereby partition #n is written.
Then, a new data area is formed (3). When the writing of data to this data area is completed, the EOD area is newly written (4), and almost the middle position of the optional device area is accessed (5), and unloading is performed here. To be At this time, as a process of the system controller 15 of the tape streamer drive, the data of the table of information to be updated including system log information and unloading position information is rewritten to the MIC 4 of the tape cassette. In this case, in the area to be located between the newly provided EOD area in the partition #n and the option device area, for example, a partial area of the original data area and the original EOD area are shown in the figure. Although included, the data in this area, which is located after the new EOD area, is made invalid after that (invalid area).

(D) Access example when MIC is present (3) Next, as an access example of the tape streamer drive corresponding to the tape cassette with MIC, data is added to the partition recorded on the magnetic tape. A case of performing the recording will be described with reference to FIG. In this case, it is assumed that the partition #n shown in the figure is the last partition on the magnetic tape 3. In this case, in the partition #n, loading is performed in the original option device area (1), and then the head of the original EOD area is accessed (2). Also in this case, the access operation is performed by the system controller 15 referring to the unloading position information stored in the MIC 4 and the area ID recorded on the magnetic tape.
Also in this case, the system log area on the magnetic tape 3 is not accessed, and the system log information is read from the MIC 4 of the tape cassette and taken into the system controller 15 side. Then, from the position of the first frame of the original EOD area, new data is added and recorded so as to overwrite the data (3). In this case, new data is additionally recorded so as to form a data area from the original EOD area beyond the area of the original system log area. As a result, the new data recording operation is performed as shown in the figure. A "new data area" will be formed in the range. After this, the EOD area is newly written (4) and the optional device area is written (5) following the new data area, and the end position of this optional device area is the new partition #.
It is considered to be the end position of n. Then, unloading is performed at a position approximately in the middle of this optional device area (6).

The embodiment of the present invention is not limited to the configurations shown in the drawings described above, and the format of data to be stored in the tape cassette, the tape streamer drive, and the MIC, The access operation and the like can be appropriately changed according to the actual usage conditions and the like. Further, as the embodiment described so far, a recording / reproducing system including an 8 mm VTR tape cassette with a nonvolatile memory for recording / reproducing a digital signal and a tape streamer drive corresponding to the tape cassette will be described. However, the present invention is not limited to this, and is naturally applied to a recording / reproducing system capable of recording / reproducing information of a video signal or an audio signal as a digital signal and a tape cassette having an MIC. Is possible.

[0070]

As described above, according to the present invention, the magnetic tape can be loaded / unloaded in the optional device area, which is an area for loading / unloading provided for each partition. For example, it is not necessary to access the device area at the head position of the magnetic tape each time loading / unloading. Further, after being loaded in the optional device area, the required access position is immediately accessed based on the unloading position information stored in the non-volatile memory and the area ID recorded on the magnetic tape. As described above, according to the present invention, the number of actions and time required for the access of the recording / reproducing apparatus for recording / reproducing with respect to the magnetic tape can be reduced to obtain a recording / reproducing system with good usability. It has the effect that In addition, since the non-volatile memory has an area for storing the same information contents as the system log area provided on the magnetic tape, the system log area on the magnetic tape is accessed to write / write data. No need to read,
Since it is sufficient to use the system log of the non-volatile memory at the time of recording / reproducing, this also reduces the number of actions required for access, thereby shortening the access time.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a tape streamer drive which is a recording / reproducing apparatus of an embodiment of the present invention.

FIG. 2 is a plan view schematically showing the internal structure of the tape cassette according to the present embodiment.

FIG. 3 is a perspective view showing the external appearance of the tape cassette according to the present embodiment.

FIG. 4 is a schematic diagram showing a data structure recorded on a magnetic tape.

FIG. 5 is a schematic diagram showing a data structure in one partition.

FIG. 6 is a schematic diagram showing a data structure of one track.

FIG. 7 is a schematic diagram showing a data structure of an ID area.

FIG. 8 is a schematic diagram showing a physical block address number on one track.

FIG. 9 is an explanatory diagram showing ID area information.

FIG. 10 is an explanatory diagram showing the definition of area IDs.

FIG. 11 is an explanatory diagram illustrating an ID area in an EOD area.

FIG. 12 is a schematic diagram showing a data structure of MIC.

FIG. 13 is an explanatory diagram showing an example of access to a magnetic tape as the recording / reproducing apparatus of the present embodiment.

14 is a flowchart showing a processing operation of the system controller for realizing the access operation shown in FIG.

FIG. 15 is an explanatory diagram showing an example of access to a magnetic tape as the recording / reproducing apparatus of the present embodiment.

FIG. 16 is an explanatory diagram showing an example of access to a magnetic tape as the recording / reproducing apparatus of the present embodiment.

FIG. 17 is an explanatory diagram showing an example of access to a magnetic tape as a recording / reproducing device.

[Explanation of symbols]

1 tape cassette, 3 magnetic tape, 4 MIC, 1
1 rotating drum, 12A, 12B recording head, 13
A, 13B playback head, 15 system controller, 17 mechanical controller, 18 modulation / demodulation circuit,
19 RF amplifier, 20 SCSI interface,
21 compression / decompression circuit, 22 buffer controller,
23 buffer memory, 25 host computer

Claims (12)

[Claims] 1. A data cassette as a tape cassette comprising a magnetic tape on which digital data is recorded and a nonvolatile memory capable of storing at least management information for managing recording / reproduction on the magnetic tape. A tape cassette characterized in that a data end area indicating the end of the area and a loading / unloading area area for loading / unloading are recordable. 2. An area ID corresponding to a type of recording area provided on the magnetic tape is set, and the recording area is recorded on the magnetic tape so as to include a unique area ID. The tape cassette according to claim 1. 3. The tape cassette according to claim 1, wherein unloading position information indicating a position where the magnetic tape is last unloaded is stored in the nonvolatile memory. 4. The tape cassette according to claim 1, wherein an area for storing information related to a usage history of the tape cassette is provided in the non-volatile memory. 5. A digital tape capable of recording digital data corresponding to a magnetic tape and a tape cassette provided with a nonvolatile memory capable of storing at least management information for managing recording / reproduction with respect to the magnetic tape. As a data recording device, after recording a data area, a data end area indicating the end of the data area and a loading / unloading area for loading / unloading can be recorded on the magnetic tape. A digital data recording apparatus, further comprising: recording control means configured to enable loading / unloading in the loading / unloading area. 6. The non-volatile memory is provided with a memory write control means capable of writing unloading position information indicating a last unloaded position. Digital data recorder. 7. The unloading position information read from the non-volatile memory and the area ID corresponding to the type of the recording area recorded on the magnetic tape are referred to, so that the tape is moved to a desired tape position after loading. 7. The digital data recording device according to claim 6, further comprising access control means capable of executing access control. 8. The digital data recording apparatus according to claim 5, further comprising a memory write control unit capable of writing information related to a usage history of the tape cassette to the non-volatile memory. 9. Digital data can be reproduced corresponding to a tape cassette provided with a magnetic tape and at least a non-volatile memory capable of storing management information for managing recording / reproduction with respect to the magnetic tape. As a digital data reproducing device, a reproducing control means capable of loading / unloading a magnetic tape in a loading / unloading area for loading / unloading provided behind a data area on a magnetic tape. A digital data reproducing device comprising: 10. The non-volatile memory is provided with a memory writing control means capable of writing unloading position information indicating a last unloaded position. Digital data playback device. 11. The unloading position information read from the non-volatile memory and the area ID corresponding to the type of the recording area recorded on the magnetic tape are referred to and the desired tape position after loading is reached. 11. The digital data reproducing apparatus according to claim 10, further comprising an access control unit capable of executing the access control of. 12. The digital data reproducing apparatus according to claim 9, further comprising a memory writing control unit capable of writing information related to a usage history of the tape cassette to the non-volatile memory.