JPH0581775A - Magnetic tape - Google Patents

Abstract

PURPOSE:To surely read data by fetching succeeding data as control information when a top pattern is detected normally and detecting a next top pattern when the top pattern is not detected. CONSTITUTION:By a DAT operation control part 14, feeding from the top part of the magnetric tape is started, when the reading of a recorded content is started, the transfer of the data from a head control part 15 to DAI12 is started. Then, when first or several time order of top pattern is detected by the DAI12, by an operation control part 5, succeeding prescribed length data is stored in the RAM 7 through a page memory 11 and an image process control part 4 as TOC data. In such a case, since the suceeding prescribed length data is stored in the memory as the TOC data after the top pattern is detected, even when the top pattern is not read because one or several top pattern are changed by the degradation of the tape, the TOC data is read surely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape used in an electronic filing apparatus for storing image data and the like, and more particularly to a magnetic tape suitable for reading management information on recorded data and loading it in the apparatus body. It is about structure.

[0002]

2. Description of the Related Art In recent years, in electronic filing apparatuses such as computers, those using magnetic disks such as fixed disks and floppy disks, and magnetic tapes have become widespread. In particular, magnetic tapes are often used as exchangeable and large-capacity recording media. Recently, as a magnetic tape,
Digital audio tapes with standardized standards are being used.

When data is recorded on a magnetic tape and an electronic filing apparatus is constructed, it is necessary to record the recording position of each file on the magnetic tape and management information containing attribute data and the like on the magnetic tape. When using the device, the management information is first read to the device side, and the file is read or updated while referring to the read management information.

Conventionally, when the management information is read from the magnetic tape, in order to read the management information, special data is recorded in the preceding stage of the position where the management information is recorded on the magnetic tape, and after this is read. The method of taking in the data of as a management information was taken.

[0005]

However, in the above-described conventional magnetic tape, an error may occur when the leading pattern is read. Further, since the management information is frequently read, special data for recognizing the head of the management information, that is, the tape portion on which the head pattern is recorded is accessed each time. For this reason, there is a risk that the tape portion will deteriorate and the leading pattern will change.

As described above, the conventional magnetic tape described above has a problem that the management information cannot be accurately read when an error occurs or the leading pattern changes.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a magnetic tape having a structure capable of reliably reading data management information.

[0008]

In order to achieve the above object, the present invention records an area in which a leading pattern indicating the start of the following management information is recorded and management information for managing the recorded data. Regions are continuously formed in this order for a plurality of times at the beginning portion (claim 1).

An area in which a first head pattern indicating the start of the following management information is recorded, an area in which a second head pattern is recorded, and an area in which management information for managing recorded data is recorded Are successively formed in this order for a plurality of times at the beginning (claim 2).

[0010]

According to the present invention, when the magnetic tape is set in the apparatus and the detection of the leading pattern is started, the succeeding data is fetched as the management information if the leading pattern is normally detected. On the other hand, if the head pattern is not detected, the next head pattern is detected. Then, subsequent data of a predetermined length is taken in as management information.

According to the second aspect of the invention, the magnetic tape is set in the apparatus and the first leading pattern is detected. When the first or some number of the first leading pattern is detected, the data of the following predetermined length is fetched, the second leading pattern is detected from the fetched data, and the second leading pattern is pulled. Subsequent data is captured as management information.

[0012]

EXAMPLE The contents recorded on the magnetic tape will be described with reference to FIG. FIG. 2 is a schematic diagram schematically showing the contents recorded on the magnetic tape. The magnetic tape 21 includes a lead-in area C, a TOC (table of contents) area D, a data area group E, and a section identification area F added to the beginning of each data area E0 in the data area group E.
Are formed. The data area E0
Are formed to have a constant or arbitrary recording area unit length.

Next, the track format of the magnetic tape will be described with reference to FIG. The magnetic tape is formatted so that various data are recorded on a large number of tracks T arranged and formed with a predetermined angle of inclination with respect to the running direction X. The format of each track T is shown in Table 1, EIAJ CP-2.
It is formed according to the standard of 305.

[0014]

[Table 1]

Each track T has a sub-region A formed at both ends thereof and a main region B formed at the center thereof.
Program number data (P. No) indicating the recording order of data, index data (Index) for area identification, etc. are recorded in the sub area A, and image data etc. are recorded in the main area B. It is designed to be.

The lead-in area C is provided to prevent the influence of rising of the head or the like and to discriminate the type of tape. In the sub-area A of each track T of the lead-in area C, as shown in FIG. 4, program number data “0BB” and index data “0
0 "is recorded in multiplex.

In the TOC area D, as shown in Table 2, tape attribute data such as a tape name, a conversion table of unused pages and erased pages, management data to be described later, tape operation history data, etc. are recorded. Has been done.

[0018]

[Table 2]

In the sub-area A of each track T of the TOC area D, program number data "000" is multiplexedly recorded as shown in FIG. 4, and the tracks T from the head to a predetermined number are recorded. Index data “AA” is recorded in the sub-area A, and index data “01” is recorded in the following track T in a multiplexed manner.

Further, in the TOC area D, management data of data of a data area group E, which will be described later, file attribute data and the like are recorded. That is, TO
As shown in Table 3, in the C area D, the program number data (P. No) and the file number data (FILEN) are associated with each data area E0 of the data area group E described later.
o), page number data of each file (PAGE N
o), an unused flag indicating whether the page is an unused page, an erased flag indicating whether the page is an erased page, an unusable flag indicating whether the page has become unusable due to deterioration or the like, and image size data indicating the size of the document. Etc. are recorded. It should be noted that "1" is set to the unused flag and the erased flag of the program numbers corresponding to the unused page and the erased page.

[0021]

[Table 3]

The data area group E has a plurality of data areas E0 for recording image data from the scanner 6 and received data from the FAX 10. In the sub-area A of the track T of the data area group E, as shown in FIG. 5, "001" is set for each data area E0 along the recording direction of the tape.
Program number data of "002", ... "N", "n + 1" ,. The data area E0 is for recording image data and the like, for example, in A3 size page units.

The section identification area F is an area in which a section identifier indicating the beginning of the data area is recorded, and this section identifier is used for finding the beginning of data retrieval. In the sub area A of the track T of the section identification area F, program number data having the same number data as the program number data of the data area group E is written. Further, from the tip of the section identification area F to the sub-areas A of the predetermined number of tracks T,
As shown in FIG. 4, index data “00” is recorded, and index data “AA” is recorded in the sub-area A of the track T following it.

Next, an example of recording the first pattern on the magnetic tape will be described with reference to FIG. FIG. 1 shows the top pattern and management information recorded on the magnetic tape, that is, the TO.
It is the schematic which represented C data typically. Magnetic tape 2
In the TOC area D of No. 1, the top pattern P1 and the TOC data TOC1 are continuously recorded multiple times in this order. As the top pattern P1, a pattern that does not occur in the TOC data TOC1 is used.

Next, a magnetic tape recording apparatus using this magnetic tape will be described. FIG. 6 is a block diagram showing the entire magnetic tape recording apparatus 1. The magnetic tape recording apparatus 1 is composed of a data control unit 2 including the functions of a digital plain paper copier (DPPC) and a digital audio tape recorder (DAT) 3.

The data control unit 2 is mainly composed of an image processing control unit 4, an operation control unit 5, a scanner 6 for reading an original, a printer 9 for copying image data, a facsimile (FA).
X) 10 and page memory 11 and the like.
Further, the scanner 6, the printer 9 and the image processing control unit 4 are provided with video interfaces (VD.IF) 61 and 91, respectively.
The data control unit 2 and DAT 3 are connected by a digital audio interface (DAI) 12, and the page memories 11 and DAI 12 are connected by a video interface (VD.IF) 111.

The image processing control section 4 is composed of a microcomputer, and internally has a bit map memory 41, a binarization processing section 42 and an image compression / expansion processing section (VCEP section).
Has 43. The bitmap memory 41 is for temporarily storing the captured data from the scanner 6 and the FAX 10 or the image data from the page memory 11 as bit information. The binarization processing unit 42 binarizes the data in the bitmap memory 41. VCEP
The unit 43 compresses the data in the bit map memory 41 and outputs it to the page memory 11 or the like, or decompresses the data from the page memory 11 and outputs it to the bit map memory 4.
It is output to 1. If necessary, VCEP
The data of the scanner 6, the FAX 10 and the page memory 11 can be directly guided to a required circuit section without the section 43.

Then, the image processing control section 4 responds to the operation of a mode switching key of the operation section 17 which will be described later, and the like.
The end of data (EOD) signal indicating the end of the data is added to the end of the image data read by the or the image data received by the FAX 10, and the image data is output to the DAT 3 via the page memory 11 or the like. , Is designed to record on magnetic tape.

Further, the image processing control section 4 can output image data from the scanner 6, image data from the FAX 10 or the like or image data from the DAT 3 to the printer 9. Further, the image processing controller 4 can output the image data read by the scanner 6 and the image data from the DAT 3 to the FAX 10.

The page memory 11 stores the image data from the image processing controller 4 or DAT 3 page by page.

The operation control section 5 is composed of a microcomputer and controls the operation of each section of the magnetic tape recording apparatus 1 in accordance with the operation of the operation section 17. Also,
The operation control unit 5 includes a random access memory (RAM) 7 that stores TOC data indicating registration date, title, and other attributes of data recorded on a magnetic tape, and a TOC management unit 8 that manages the TOC data. The TOC data recorded on the magnetic tape is also managed. Further, the TOC management unit includes a timer 81 for managing the TOC data.

That is, when the magnetic tape is set, the TOC management unit 8 reads the TOC data from the magnetic tape and stores the TOC data in the RAM 7, and also records image data on the magnetic tape by the operation unit 17, for example. TO in the RAM 7 according to a processing command such as erase or erase
Update C data.

Further, the operation control unit 5 is adapted to record the TOC data stored in the RAM 7 on the magnetic tape, for example, at regular time intervals upon completion of use of the magnetic tape or time management by a timer.

In the management of the TOC data, T
The image data deleted on the OC data is updated and deleted when the next image data is recorded on the magnetic tape.

The operation unit 17 includes a key for inputting TOC data for managing data recorded on the magnetic tape, a file mode for recording image data read by the scanner 6 on the magnetic tape, and data received by the FAX 10. A mode switching key for switching the FAX mode to be recorded on the magnetic tape, a key for setting the image density at the time of reading an original by the scanner 6, a required number of sheets at the time of printing, and other keys for searching for data recorded on the magnetic tape. And a display circuit 171 for confirming the operation content.

Further, the operation control section 5 executes the search processing based on the search instruction from the operation section 17 to execute the search process.
The TOC data in the RAM 7 is referred to via the C management unit 8 and the display circuit 171 in the operation unit 17 is caused to display a file name for retrieval or the like.

The DAT 3 is composed of a DAT operation control section 14, a head control section 15 and the like. The head controller 15 and the data controller 2 are connected by a digital audio interface (DAI) 13.

The DAT operation control section 14 controls the operation of each section of the DAT 3, and receives a control command from the operation control section 5 to instruct the head control section 15 to perform recording, reproduction, erasing and the like. I am trying. Head controller 15
Is for driving and controlling a magnetic head, a reel motor, and the like (not shown), and a random access memory / error correction code section (RAM / ECC) 151 is provided therein. The RAM / ECC 151 adds an error correction code to the input data from the data control unit 2 at the time of recording and applies error correction to the data from the magnetic tape based on the error correction code at the time of reproduction.

Next, the TOC data reading operation will be described with reference to the flowchart of FIG. When the DAT operation control unit 14 starts feeding from the leading end of the magnetic tape and starts reading the recorded contents, the head control unit 15 starts data transfer to the DAI 12 (step S1). Next, it is determined whether or not the DAI 12 detects the first leading pattern, and if not detected (NO in step S2), the process returns to step S1 to prepare for the detection of the next leading pattern. If the DAI 12 detects the first or some number of leading patterns in step S2 (YES in step S2), the operation control unit 5 sends subsequent predetermined length data through the page memory 11 and the image processing control unit 4. The RAM 7 is stored as TOC data (step S3).

That is, after detecting the head pattern, the data of a predetermined length thereafter is stored in the memory as TOC data, so that one or several head patterns are changed due to deterioration of the tape and the head pattern cannot be read. However, since there is a high probability that the top pattern that has not changed in the multiplex recording exists, the top pattern can be read with a high probability, so that the TOC data can be read reliably.

Next, regarding the second embodiment of the magnetic tape,
This will be described with reference to FIGS. 8 and 9. FIG. 8 shows the first head pattern, the second head pattern and the T recorded on the magnetic tape.
It is the schematic which represented OC data typically. In the TOC area D of the magnetic tape 21, the first start pattern P11, the second start pattern P21 and the TOC data TOC11
However, multiple recording is continuously performed in this order a plurality of times.

When the head pattern is added to the management information, if the same data as the head pattern exists in the management information, the head of the management information is mistakenly taken in, so that the structure of the head pattern is limited. If the data length of the head pattern is increased, the probability that the same data as the head pattern occurs in the management information decreases, but since the head pattern is read by hardware, that is, the DAI 12, the data length of the head pattern is reduced. Becomes larger, DAI
The configuration of 12 becomes complicated. Therefore, it is possible to allow the same data as the first head pattern to exist in the TOC data and shorten the data length of the first head pattern to make the structure of the DAI 12 that detects the first head pattern complicated. The second top pattern is used, so that

Next, the TOC data reading operation will be described with reference to the flowchart of FIG. When the DAT operation control unit 14 starts feeding from the leading end of the magnetic tape and starts reading the recorded contents, the head control unit 15 starts data transfer to the DAI 12 (step S11). Next, it is determined whether or not the DAI 12 has detected the first first head pattern, and if not detected (NO in step S12), the process returns to step S11 to prepare for detection of the next first head pattern. Step S12
DAI12 is the first or first time
If the leading pattern of is detected (YES in step S12)
S) Then, the operation control unit 5 stores the subsequent predetermined length data in the RAM 7 via the page memory 11 and the image processing control unit 4 (step S13).

Next, the address pointer of the RAM 7 is set to the head of the data (step S14), and the data of the second head pattern length is read (step S15). Then, it is determined whether or not the read data matches the second head pattern, and if they do not match (N in step S16).
O), increment the address pointer (step S17), and return to step S15.

This is, for example, the first head pattern P11.
If the 2-bit data immediately before is "01", then this is read as 8 bits by hardware as a part of the first start pattern, and "01" is read at the start of the second start pattern P21. , It is determined that the second head pattern does not match the second head pattern. Therefore, in step S17, the address pointer is shifted bit by bit to detect the second head pattern P21.

On the other hand, in step S16, if the read data matches the second head pattern (YES in step S16), the subsequent predetermined length data is fetched as TOC data (step S18).

That is, after the first head pattern is detected, the second head pattern is further detected, and the subsequent data of a predetermined length is stored in the memory as TOC data. Therefore, the first head pattern is included in the TOC data. Even if the same data as the pattern exists, the TOC data can be accurately read by reading the second head pattern.

[0048]

As described above, according to the present invention, since the leading pattern and the management information are continuously recorded in this order, one or several leading patterns are changed due to deterioration of the tape, and the leading pattern is not detected. However, since there is a high existence probability of the unchanged start pattern in the multiplex-recorded data, the start pattern can be detected with a high probability, so that the reading of the management information is ensured.

Further, even if the same data as the first head pattern exists in the management information, the second head pattern makes it possible to read the management information and further shorten the data length of the first head pattern. Magnetic tape can be provided. Further, by shortening the data length of the first start pattern, a simplified device can be used as the device for detecting the first start pattern.

[Brief description of drawings]

FIG. 1 Leading pattern and TOC recorded on a magnetic tape
It is the schematic which represented the data typically.

FIG. 2 is a schematic diagram schematically showing the contents recorded on a magnetic tape.

FIG. 3 is a diagram showing a track format of a magnetic tape.

FIG. 4 is a diagram showing the contents recorded at the beginning of a magnetic tape.

FIG. 5 is a diagram showing contents recorded in a data area and a section identification area of a magnetic tape.

FIG. 6 is a block diagram showing an entire magnetic tape recording device.

FIG. 7 is a flowchart showing the operation of the first embodiment.

FIG. 8 is a first head pattern recorded on a magnetic tape,
It is the schematic which represented the 2nd head pattern and TOC data typically.

FIG. 9 is a flowchart showing the operation of the second embodiment.

[Explanation of symbols]

1 Magnetic Tape Recording Device 2 Data Control Section 3 Digital Audio Tape Recorder (DAT) 4 Image Processing Control Section 5 Operation Control Section 6 Scanner 7 Random Access Memory (RAM) 8 TOC Management Section 9 Printer 10 Facsimile (FAX) 11 Page Memory 12 , 13 Digital audio interface (D
AI) 14 DAT operation control unit 15 head control unit 17 operation unit 21 magnetic tape 41 bitmap memory 42 binarization processing unit 43 image compression / expansion processing unit (VCEP unit) 61, 91, 111 video interface (VD.I)
F) 81 timer 151 random access memory / error correction code section 171 display circuit P1 start pattern P11 first start pattern P21 second start pattern TOC1, TOC11 TOC data

Claims (2)

[Claims] 1. An area in which a head pattern indicating the start of the following management information is recorded and an area in which management information for managing recorded data is recorded are successively formed in this order at the beginning portion for a plurality of times. A magnetic tape that is made up of. 2. An area in which a first head pattern indicating the start of the following management information is recorded, an area in which a second head pattern is recorded, and an area in which management information for managing recorded data is recorded. Is a magnetic tape that is formed in the beginning of the tape several times in succession in this order.