JPH04286775A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To obtain correct reproducing data even when one of several magnetic heads is faulty by correcting an error with an error correction circuit capable of correcting integer number of words at the time of reproducing. CONSTITUTION:An error detection and correction code C3 is added in a prescribed unit to input daya D0 seccessively inputted to the magnetic recording and reproducing device by means of an encorder 32, and an interleaving processing is executed for the D0 and C3 in interleaving processing circuits 33A and 33B. This device is provided with a magnetic recording means 13 recording output data REC of the circuits 33A and 33B on a magnetic tape, deinterleaving processing circuits 42A and 42B performing the deinterleaving processing for reproducing data PB, and an error correction circuit 43 conducting the error correction of the output data D11. The circuits 33A and 33B and the circuits 42A and 42B execute the interleaving processing and the deinterleaving processing, respectively, between the tracks which are integer multiple of the number of the magnetic head mounted on a drum.

Description

[Detailed description of the invention]

0001

[Table of Contents] The present invention will be explained in the following order. Industrial application field Conventional technology (Figs. 7 and 8) Means for solving the problem to be solved by the invention (Figs. 4 and 5) Effect (Fig. 4)
and FIG. 5) Embodiment (1) Overall configuration (FIG. 1) (2) Data recorder control device (FIGS. 2 to 6) (3) Effects of the embodiment (4) Effects of the invention of other embodiments

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording/reproducing device, and can be applied to, for example, an external storage device for a computer.

0003

2. Description of the Related Art Conventionally, in this type of magnetic recording and reproducing apparatus, recording tracks are sequentially formed diagonally on a magnetic tape.
A so-called ID-1 format data recorder that can record and reproduce desired data at high density has been proposed (ANSI x3.175-199019m).
m Type ID-1 Recorded Inst
rumentation).

That is, as shown in FIG. 7, in this type of data recorder, a magnetic tape 1 is wound around a rotating drum that rotates at a predetermined speed, and by running the magnetic tape 1 at a predetermined speed, the magnetic tape 1 is moved around the rotating drum. Recording tracks TR (TR1, TR1,
TR2, TR3, TR4, TR1, TR2, . . . ), thereby recording desired data on the recording track TR1. Furthermore, at this time, the data recorder has recording tracks T extending in the longitudinal direction at the upper and lower ends of the magnetic tape 1.
A, CTL, and TC are formed, and the track set ID of the recording track TR is recorded in the recording track CTL.

[0005] Here, the track set ID is absolute position information starting from the beginning of the magnetic tape 1, and is inserted between predetermined synchronization signals and is recorded on the recording track TR at four track cycles. There is. Furthermore, the recording tracks TA and TC are designed to be able to record user management data, etc.
By reproducing the TL and TC, data recorded at high density on the recording track TR can be easily searched.

Furthermore, in the data recorder, when recording data on the recording track TR, the data is recorded with a parity code for error detection and correction, which is a so-called product code. It is designed to ensure reliable recording and reproduction. That is, as shown in FIG. 8, the data recorder has a predetermined unit (=36,
8 [BITE]), the data DATA is divided into 306 blocks, and each block is divided into 306 blocks using the Reed-Solomon
) error detection and correction code (that is, C2 code) is added.

Further, after dividing the block into first and second fields FIELD0 and FIELD1, a Reed-Solomon error detection and correction code (that is, a C1 code) is applied to each field FIELD0 and FIELD1 so as to be orthogonal to the C2 code. ) is added. This allows the data recorder to improve the bit error rate by correcting errors in reproduced data using the C1 and C2 codes during reproduction.

Furthermore, in the data recorder, when recording the data DATA to which the C1 and C2 codes have been added in this way onto the magnetic tape 1, interleaving processing is performed for each recording track TR, and as a result, even if a dropout occurs, the interleaving process is performed. , the data DATA can be reliably reproduced. That is, in the data recorder, arrows a1, a2, ..., an-1, an, a
For the data DATA input in the order shown by n+1, an+2, ... ax-1, ax,
As shown by b2, .

Furthermore, at this time, in the data recorder, a synchronizing signal SYNC and a sync block data ID are added to each predetermined unit (hereinafter referred to as a sync block), and preamble and postamble data are added as a whole to the data DATA. Record. As a result, during playback, the magnetic recording device uses the track sync data included in the preamble as a reference to generate the sync signal SYNC, sync block data ID, and data DATA.
can be reproduced and deinterleaved based on the synchronization signal SYNC and the sync block data ID.

Furthermore, by deinterleaving, even if dropout occurs, C1 and C
This effectively prevents errors exceeding the error correction capability of the two codes from concentrating in one place.

[0011]

[Problem to be solved by the invention] By the way, such I
In a D-1 format data recorder, data can be recorded using multiple magnetic heads, and if one of the magnetic heads fails,
It becomes difficult to reproduce correct data. The present invention has been made in consideration of the above points, and it is an object of the present invention to propose a magnetic recording/reproducing device that can reproduce correct data even if one of the plurality of magnetic heads fails.

0012

[Means for Solving the Problems] In order to solve the problems, the present invention uses a plurality of magnetic heads A to H mounted on a drum to sequentially record recording tracks TR diagonally in the longitudinal direction of the magnetic tape 1. and the desired input data W
In the magnetic recording and reproducing devices 12 and 13 that record R, an encoder 32 adds an error detection and correction code C3 in a predetermined unit to the sequentially input input data D0, and an interleaving process is performed on the input data D0 and the error detection and correction code C3. interleaving processing circuits 33A, 33B, magnetic recording means 13 for recording output data REC of the interleaving processing circuits 33A, 33B on the magnetic tape 1, and reproducing the output data REC recorded on the magnetic tape 1 to produce reproduced data PB. a magnetic reproducing means 13 for outputting, a deinterleaving processing circuit 42A for deinterleaving the reproduced data PB,
42B, and an error correction circuit 43 that performs error correction processing on the output data D11 of the deinterleave processing circuits 42A and 42B.
The interleaving processing circuits 33A, 33B and the deinterleaving processing circuits 42A, 42B correspond to the number (8) of magnetic heads A to H mounted on the drum.
Interleave processing and deinterleave processing are performed between recording tracks (24) that are an integer multiple (3) of the number of recording tracks, and the error correction circuit 43 has error correction capability for an integer multiple (3) of words.

[0013]

[Operation] For the number of magnetic heads A to H (8), interleave processing and deinterleaving processing are performed between recording tracks (24) that are an integral multiple (3) of the number of magnetic heads A to H, and the number of words is an integral multiple (3) of the number of magnetic heads A to H (8). If the error correction circuit 43 having the error correction capability performs error correction, correct reproduced data D12 can be obtained even if the magnetic head fails.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

(1) Overall configuration (1-1) Computer system configuration In Figure 1, 1
0 generally shows the schematic configuration of a computer system to which the present invention is applied, in which write data WR sent from the host computer 11 together with a write request is transmitted through the data recorder control device 12 as record data REC,
The data is supplied to the data recorder 13 in ID-1 format, thereby writing the write data WR onto the recording track on the magnetic tape.

Furthermore, in response to a read request input from the host computer 11, the magnetic tape of the data recorder 13 is played back, and the resulting playback data PB is transmitted through the data recorder control device 12 to the read data R.
D is input to the host computer 11.

The data recorder control device 12 is composed of a host interface control section 14 and a format control section 15.
controls the channel interface with the host computer 11, and the format control unit 15 controls the memory 1.
6 is used to format the data to be sent to and received from the data recorder 13. Also, the host interface control unit 14
Control information is exchanged between the format controller 15 and the format controller 15 with reference to the control table 17.

As a result, in the computer system 10, since the data recorder control device 12 is provided, the data recorder 13 can be connected to the external storage device of the host computer 11 using an interface similar to a conventional magnetic tape device on the host computer 11 side. It is designed so that it can be used as a

(2) Data recorder control device Here, FIG.
As shown in FIG. 2, in the data recorder control device 12, 8-bit data output from the host computer 11 is applied to the buffer memory 22 as 4-channel 8-bit parallel write data D0. As a result, in the data recorder control device 12, the write data D0 is divided into four channels and processed in parallel, thereby simplifying the overall configuration.

As shown in FIG. 3, the buffer memory 22 once stores the write data D0 and then sequentially outputs the write data D0 in predetermined units.
Every 8 [BYTE] (hereinafter, the amount of data is referred to as 1 unit)
, 320 [BYTE] worth of subcode data SCD
Add. As a result, the buffer memory 22 generates first buffer data D2 in which the subcode SCD is added in units of 32,768 [BYTE] of the write data D0, and outputs it to the multiplexer 25 having an addition circuit configuration.

When one unit of the first buffer data D2 is less than 32,768 [BYTE], the multiplexer 25 adds the first supplementary data PD1 to reduce the total data amount per unit to 32,768 [BYTE]. ,768 [B
YTE] to generate fourth buffer data D4. The C3 code generation circuit 32 generates fourth buffer data D.
One unit of 4 is divided into 352 data blocks, and an error detection and correction C3 is generated and added to each data block.

[0022] As a result, the C3 code generation circuit 32
Buffer data D4 of code length N (N = 102 [BI
After converting into Reed-Solomon code with parity number P (P=8 [BITE]), recording track data D5
Output as .

As shown in FIG. 4, the interleave memory circuit 33A is configured to be able to store 24 units of recording track data D5, and generates recording track data D5 based on the address data output from the address generation circuit 33B. By sequentially storing, 32,768×24 [BYTE] of write data D0 and the corresponding subcode SCD are stored.

At this time, the interleaved memory circuit 33A
stores recording track data D5 for each data block, and outputs the recorded track data D5 stored in a different order from that at the time of writing. That is, as shown in the relationship between the arrows a and b described above with reference to FIG. 8, the order is reversed from that at the time of writing and output, thereby interleaving the 24 units of recorded track data D5.

The multiplexer 34 receives the interleaved recording track data D6 and adds second supplementary data PD2 of 204 [BITE] and synchronization code data to the recording track data D6. As a result, the multiplexer 34 corrects the data amount of the recording track data D6 so that one unit of the recording track data D6 matches the user data amount (36,108 [BITE]) of one recording track in the D-1 format. The corrected data is output as recording data REC.

As a result, the data recorder control device 12 transfers the recorded data REC to the data recorder 13.
According to the format of the data recorder 13, interleaving processing is performed and error correction codes are added and recorded. At this time, in the data recorder control device 12, so that one unit of recording data REC is recorded on one recording track of the data recorder 13,
It operates in synchronization with the data recorder 13.

As a result, in the data recorder control device 12, the 24 units of recording track data D5 are interleaved in the interleave memory 33A, so that the recording track data D5 is shuffled to 24 recording tracks and recorded. Thus, in the data recorder 13, by performing interleave processing within a recording track and interleaving processing between recording tracks, it is possible to further improve the bit error rate compared to the prior art.

As shown in FIG. 5, in the data recorder 13, eight magnetic heads A to H are arranged at equal intervals on the drum. Interleaving processing of the data recorder control device 12 is set. This allows the data recorder control device 12 to correct bit errors in reproduced data even if one of the magnetic heads A to H fails.

That is, as shown in FIG.
If, for example, magnetic head A of ~H fails, that magnetic head A out of the 24 interleaved tracks
Correct data cannot be reproduced from the recording tracks with track numbers 0, 8, and 16 corresponding to the track numbers 0, 8, and 16. However, in this embodiment, by performing interleave processing among the 24 recording tracks, errors can be corrected in the data recorded on each recording track based on the data recorded on the remaining recording tracks.

For example, in the data of data number 2, correct data can be obtained from track numbers 1-7, 9-15, 17-23, and track numbers 0, 8,
Erroneous data is reproduced from 16 recorded tracks. Therefore, in the case of this embodiment, by generating a Reed-Solomon code with an 8-byte code length, if the error correction circuit on the playback side has a 3-word correction capability, track numbers 1 to 1 can be corrected.
It is possible to correct errors in the reproduced data of track numbers 0, 8, and 16 from the reproduced data of tracks 7, 9 to 15, and 17 to 23, and even if one of the magnetic heads A to H is out of order, the correct data can be corrected. You can see that it can be played.

In other words, by performing interleaving processing between recording tracks that are an integer multiple of the number of magnetic heads, an error correction circuit capable of correcting errors for an integer multiple of the number of words can be used to detect errors in the magnetic head. The correct data can be played even if Therefore, in the data recorder control device 12, an error correction circuit having a three-word correction capability is used on the reproduction side to correct errors in the reproduced data.

That is, the data recorder control device 12
Reproduction data PB output from data recorder 13 is provided to deinterleave memory 42A.

The deinterleave memory 42A has the same configuration as the interleave memory 33A, and sequentially inputs the reproduced data PB and outputs it in a predetermined order based on the write and read addresses output from the address generation circuit 42B. The playback data is deinterleaved by

The C3 error correction circuit 43 has a three-word correction capability, and sequentially corrects errors based on the C3 code added to the reproduced data D11, and corrects the errors in the error-corrected data D.
12 is output to the buffer memory 22. When the buffer memory 22 has accumulated a predetermined amount of the reproduction data D12, the buffer memory 22 outputs the reproduction data D12 in response to a command from the phosphor computer 11.

(3) Effects of the Embodiment According to the above configuration, by recording data using 8 magnetic heads after performing interleave processing among 24 recording tracks, even if one of the magnetic heads fails, Even in this case, correct data can be reproduced using a C3 error correction circuit with 3-word correction capability.

(4) Other Embodiments Although the above-mentioned embodiment describes the case where eight magnetic heads are used, the present invention is not limited to this, and desired data can be obtained using a plurality of magnetic heads. It can be widely applied when recording.

Further, in the above-described embodiment, the present invention was applied to a D-1 format data recorder, but the present invention is not limited to this, but can be widely applied to magnetic recording devices that record various data. can do.

[0038]

As described above, according to the present invention, when desired data is recorded using a plurality of magnetic heads, interleaving processing is performed between recording tracks that are an integral multiple of the number of magnetic heads. By correcting errors during reproduction using an error correction circuit having the ability to correct an integer number of words, it is possible to obtain a magnetic recording and reproducing apparatus that can reproduce correct data even if one of the plurality of magnetic heads fails.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a computer system according to one embodiment of the present invention.

FIG. 2 is a block diagram showing a data recorder control device.

FIG. 3 is a schematic diagram showing the recording format on the magnetic tape.

FIG. 4 is a schematic diagram for explaining interleave processing.

FIG. 5 is a schematic diagram showing the arrangement of magnetic heads.

FIG. 6 is a schematic diagram showing the arrangement of recorded data.

FIG. 7 is a flowchart for explaining the D-1 format.

FIG. 8 is a schematic diagram for explaining the interleaving process.

[Explanation of symbols]

11...Host computer, 12...Data recorder control device, 13...Data recorder, 15...Format control unit, 22...Buffer memory, 32...C3 code generation circuit, 33A...Interleave memory, 42A
...Deinterleave memory, 43...C3 error correction circuit.

Claims (1)

[Claims] Claims: 1. A magnetic recording and reproducing apparatus that uses a plurality of magnetic heads mounted on a drum to sequentially form recording tracks obliquely in the longitudinal direction of a magnetic tape to record desired input data. an encoder that adds an error detection and correction code to the input data in predetermined units; an interleave processing circuit that interleaves the input data and the error detection and correction code; and output data of the interleave processing circuit that is recorded on the magnetic tape. magnetic recording means for reproducing the output data recorded on the magnetic tape to output reproduced data; a deinterleaving processing circuit for deinterleaving the reproduced data; and an error correction circuit that performs error correction processing on output data, and the interleave processing circuit and deinterleave processing circuit include:
For the number of magnetic heads mounted on the drum,
A magnetic recording and reproducing apparatus characterized in that the interleaving process and the deinterleaving process are executed between the recording tracks that are an integral multiple of the number of recording tracks, and the error correction circuit has an error correction capability of the number of words that is an integral multiple of the number of recording tracks.