JPH02230537A - Magneto-optical disk control system - Google Patents

Abstract

PURPOSE:To shorten a time required for write by arranging plural heads on the same track. CONSTITUTION:A magneto-optical disk device 1 which performs the write and the readout of information on/from a magneto-optical disk medium 11, and a magneto-optical disk controller 2 which controls the magneto-optical disk device 1 are provided, and the device 1 is provided with the plural heads 12-14 equipped with erasure/write functions, and they are arranged on the same track. The head state register 21 of the controller 2 stores the states of the plural heads 12-14, and an operating mode control means 22 reads out the content of the head state register 21, and decides an operating mode corresponding to the number of heads operating normally, and sends a head control signal. Head control circuits 15-17 correspond to each of the heads 12-14, respectively, and control the operations of the heads 12-14 based on the head control signal. In such a way, the time required for the write of data can be shortened.

Description

[Detailed Description of the Invention] [Summary] The purpose of the present invention is to provide a magneto-optical disk device and a magneto-optical disk for controlling the magneto-optical disk device, with the purpose of reducing the time required for writing data regarding the control of a magneto-optical disk. In the control device, heads with erase/write/read functions are arranged in the same rack, and a head status register is provided to store the status of the plurality of heads, and the contents of the head status register are provided. an operation mode control means for determining an operation mode according to the number of normally operating heads and sending out a head control signal; and an operation to be performed by the head corresponding to each of the plurality of heads based on the head control signal. a head control circuit that controls the head control circuit, and according to the contents of the head status register, assigns an operation to be performed to the normally operating heads based on the number of normally operating heads, and according to the number of normally operating heads. Then, the speed is adjusted so that the number of revolutions of the magneto-optical disk medium required for a write operation is minimized.

[Industrial application field] The present invention relates to a control method for a magneto-optical disk device.

Optical disk drives are capable of higher recording densities than magnetic disk drives, so they are used for large-capacity files, but the write-once type is currently most commonly used.
Its uses were limited because it could not be rewritten. Recently, rewritable optical disk devices are coming to the stage of practical use.

As one of the rewritable (erasable) optical discs,
There is a magneto-optical disk.

Magneto-optical disks always require erasing before writing, and in addition to reading for checking after writing, the disk medium requires three revolutions to write one block. , it is desired to shorten the time required for this writing.

[Conventional technology]

FIG. 4 is a diagram showing the principle of erasing/recording/reproduction of a magneto-optical disk.

As shown in the figure, information is magnetically recorded on a magneto-optical disk in a direction perpendicular to the recording layer of the medium.

Before writing to a magneto-optical disk, it is necessary to erase the disk to make the direction of magnetization of the medium constant.

As shown in Figure 4(a), erasing is performed by irradiating the medium with a laser beam focused on a minute spot, locally lowering the coercive force of the recording layer, and applying an external magnetic field using a high-speed coil to erase data in a fixed direction. It is magnetized in the downward direction (in the case of the figure).

For recording, as shown in the same figure (b), a laser beam focused on a microscopic tube 1 is emitted onto the medium, and a current opposite to that used for erasing is applied to the higher coil according to the data to be recorded. flow. If the data is "1", a current flows and reverses the direction of magnetization in the laser irradiated area. The data is"'
0", the direction of magnetization remains the same. The medium has a very strong coercive force at room temperature, so recorded information is stably retained.

Reproduction is performed by irradiating the medium with a laser beam focused on a minute spot and depending on the properties of the light reflected from the medium, as shown in FIG. In other words, it utilizes the Kerr effect in which the plane of polarization of light reflected from a medium rotates clockwise or counterclockwise depending on the direction of magnetization of the medium, and the reflected light is vertically rotated by a polarizing beam splinter. The light is separated into polarized light and horizontally polarized light, and the data is read out based on the detection output.

As described above, a magneto-optical disk is an erasable disk medium, but when writing one block of data to a medium using the write command, the original data must first be erased, and then the other data must be written. After waiting for one rotation, data is written, and after one more rotation, the data written on the medium is read to check whether the data can be written normally.

In such a rewritable magneto-optical disk, at least three rotations of the disk are required to write one bronc.

[Problems to be Solved by the Invention] - As explained in Section L, in conventional magneto-optical disk drives, three revolutions of the disk are required to write one block of data on the medium using a write command. However, there is a problem that the processing time is long.

The problem to be solved by the present invention is to provide a magneto-optical disk control system that eliminates such conventional problems.

[Means to solve the problem]

FIG. 1 is a block diagram showing the configuration of the present invention.

In the figure, reference numeral 1 denotes a magneto-optical disk device that writes information on a magneto-optical disk medium 11 and reads information from the medium 11.

Reference numeral 2 denotes an optical disk control device which controls the magneto-optical disk device 1.

]2 13 and 14 are a plurality of heads equipped with erase/read/write functions, and are arranged in the same rack.

Reference numeral 21 denotes a held state register, and the plurality of heads 12
, 13, 1.4 states are stored.

Reference numeral 22 denotes an operation mode control means which reads the contents of the head status register 21, determines the operation mode according to the number of normally operating heads, and sends out a head control signal.

15 16. 17 is a head control circuit which controls the plurality of heads 12. 13. 14, and controls the operation of the head based on the head control signal.

[For production]

In the present invention, the magneto-optical disk device 1 is equipped with a plurality of (basically three) erasing/reading/writing heads, and even if one or two heads are broken, the magneto-optical disk can be read/written. It attempts to compensate for write operations.

In general, the head of a magneto-optical disk is configured such that one head can perform erasing, writing, and reading. Such heads 12, 13. 14 are arranged as shown in FIG. That is, with respect to the rotational direction of the disk media 11 shown by the arrow, from "second flow" to "12. 13. Arrange in the order of 14.

These heads 12, 13. The status of 14 is checked during diagnosis and maintenance, and the status of whether or not it operates normally is stored in the ghent status register 21.

The operation mode control stage 22 reads the head status register 21, determines the operation mode of the magneto-optical disk based on the contents thereof, and sends out a control signal that determines the operation to be performed by a normally operating head.

Each head 12, 1.3. Head control circuit 15 corresponding to 14, 1.6. 17 is operation mode control 1,000 steps 2
Based on the control signal from 2, the operation of the corresponding head is controlled.

If none of the heads are broken, disk medium 1
The most upstream head 12 in the first rotational direction is responsible for erasing, the second head 13 is responsible for writing, and the most downstream head 14 is responsible for reading and checking. In this state, writing of one block is completed in at least one rotation.

Assuming that the head 12 is broken, the head 13
, determines the mode in which a write operation is performed using the head 14, sends a head control signal, and controls the head control<In circuit 16.
17. In this case, the head 13 is used to first perform erasing. After one rotation, the head 13
Writing is performed by the head 14, and reading checking is performed by the head 14 (erasing may be performed by the head 14). If head 13 is broken, the remaining heads 12. 14, and if head 14 breaks, the remaining head 12. 13 is used to control the same operation. In this case, writing of one block will be completed in two revolutions.

If two heads are broken, the remaining one head is controlled to perform writing. In this case, as before,
Erase, write, read and change with one head,
Three rotations are required to write one block.

〔Example〕

FIG. 2 is a diagram showing the configuration of an embodiment of the present invention.

In the figure, ■ is a magneto-optical disk device, and 2 is a magneto-optical disk control device.

11 is a magneto-optical disk medium;]2. 13. 1
4 is the head.

14, 15. 16 is a head control circuit corresponding to each head.

23 is a microprocessor (MPU), which controls the entire magneto-optical disk control device 2;

24 is an interface control circuit, which connects the head control circuits 15, 16 through an interface line 30. 17.

21 is a head status register, each head 12
, 13. It consists of a box that stores 1 bit corresponding to 14. Heads 12, 13. If all 14 are normal, all "0" are set. When the head 12 is broken, "'1" is set in the corresponding boxes 21 and 2, and when the head 13 is broken, "'1" is set in the corresponding boxes 2] and 3.
"1" is set, and if the head 14 is broken, "1" is set in the box 2114.

The microprocessor sensor 23 reads the contents of the head status register 21, determines the operation mode based on the value, and in the case of a write command, erases/writes/reads the normally operating head F. A control command is sent via the interface control circuit 24 to allocate the .

Head control circuits 15, 16, 17 corresponding to each head 12, 13, 14 erase/delete each head based on control commands sent from the magneto-optical disk controller.
The write/read circuit is controlled to cause the non-faulty heads to perform their assigned operations.

When an input/output command is issued and a write command for one block is executed when all heads are normal,
The microprocessor 23 causes the head to seek the track containing the target block.

? After that, it is confirmed that the values of the head status register 2I are all "0", and control is performed to perform a write operation using three heads.

When the magneto-optical disk rotates and a read signal from the head 12 detects that the target block is below the head 12, the microprocessor 23 sends an erase operation to the head control circuit 15 via the interface control circuit 24. Give a control command to start. Next, when the block comes under the head 13, the microprocessor 23 issues a command to the head control circuit 16 of the head 13 to start a write operation. Furthermore, when the disk medium 11 rotates and the relevant float comes under the head 14, the head 14
A read command is issued to the head control circuit 17 of. The error detection and correction code (ECC) portion of this read data is checked by an error check circuit (not shown) to determine whether the write operation has been completed normally.

Next, the operation when the head 12 is broken, for example, will be explained. When the head 12 is broken, the head status register 21
The microprocessor 23 sets "1" in the head status register 211■ after the seek operation.
It is checked that the A value of 1 is "゜1゛, "0゜'', ゛0'', it is recognized that the head 12 is broken, and the operation mode is determined. The microprocessor 23 determines that the head 13 should perform an erase operation, and when the target block comes under the head 13, the head control circuit 16
A command is issued to start the erase operation. After that, it rotates once and waits for the block to come under the head 13 again, and issues a command to the head control circuit 16 to start the write operation.

Immediately thereafter, when the block comes under the head 14, a check is performed by issuing a command to the head control circuit 17 to start the read operation.

FIG. 3 is a diagram showing the configuration of a head control circuit in one embodiment of the present invention.

In the figure, 15, 16. 17 is a head control circuit, and 24 is an interface control circuit.

31-39 and 301-304 are interface lines.

31, 34. 37 is an erase gate control line, which connects each head control circuit 15, 16. The erase gate 1 in 17 is controlled to operate or disable the erase circuit.

32, 35. 38 is a write game I/control line;
Respective head control circuits 15, 16. The write gate in 17 is controlled to activate or deactivate the write circuit.

33, 36. 39 is the write game 1 control line,
The readout gates in each head control circuit 15, 16, 1.7 are controlled to activate or deactivate the readout circuit.

301 is a write data line, which switches a switch 311 under the control of a write data switching control line 302, and connects each head control circuit 15, 1.6. 17 to any one of the write data lines 305, 306, and 307.

303 is a continuous data line, and the switch 312 is switched under the control of the read data switching control line 304.
Each head control circuit 15, 16. 17 read signal lines 308, 309, and 310.

1A [Effects of the Invention] As is clear from the above description, according to the present invention, by arranging a plurality of heads on the same track, the time required for writing can be significantly shortened, and even if at least one normal head is There is a significant industrial advantage in that it is possible to continue operating as long as it remains.

21 is a head status register, 22 is an operation mode control means, 23 is a microprocessor (MPU), 24 is an interface control circuit, 30 to 39, 301 to 310 are interface lines,
311 and 312 indicate switches.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a diagram showing the configuration of an embodiment of the invention, FIG. 3 is a diagram showing the configuration of a head control circuit in an embodiment of the invention, FIG. 4 is a diagram showing the principle of erasing/recording/reproduction of a magneto-optical disk. In the figure, 1 is a magneto-optical disk device, 2 is a magneto-optical disk controller, 11 is a magneto-optical disk medium, 12, 13, 14 is a head, 15. 16. 17 is a head system 1 wholesale circuit, medium ↓ ↓ ↓ ↓ 宕↓ ↓ ? ↓ Erasing, recording and reproducing (a) (b) (C) Diagram showing the principle of erasing/recording/reproducing of magneto-optical disks

Claims (1)

[Claims] Information is written on a magneto-optical disk medium (11), and the medium (
11); a magneto-optical disk device (1) that reads from the
In the magneto-optical disk control device (2) that controls the magneto-optical disk device (1), a plurality of heads (12) having erase/write/read functions;
(13) and (14) on the same track and a head status register (21) that stores the status of the plurality of heads (12), (13), and (14); and the head status register. an operation mode control means (22) that reads the contents of (21), determines an operation mode according to the number of normally operating heads, and sends a head control signal; and the plurality of heads (12), (13), ( head control circuits (15) and (16) corresponding to each of (14) and controlling the operation to be performed by the head based on the head control signal;
), (17), and assigns the operation to be performed to the normally operating heads based on the number of normally operating heads indicated by the contents of the head status register (21), and assigns the operation to be performed to the normally operating heads, and A magneto-optical disk control system characterized in that the number of revolutions of a magneto-optical disk medium (11) required for a write operation is controlled to be minimized accordingly.