JPH1116258A - Disk device and method for deciding recording capacity in recording area - Google Patents

Abstract

PROBLEM TO BE SOLVED: To absorb characteristic tolerance of a recording/reproducing head and a medium, to secure recording capacity and to enhance reliability by changing a zone table according to a combined characteristic between each head and the medium in the inside of a disk device. SOLUTION: Related to all head addresses, recording/reproducing characteristics in combination between respective recording/reproducing heads and their recording areas are examined, and a margin test is executed. Whether or not a signal margin is secured when the zone table of a standard default value is adopted in the combination between the heads in respective head addresses and the recording areas is decided from the test result. When not, recording density is lowered from the default value, and when secured, the recording density is raised, and the result is stored in a memory. When the processing of the head address is ended, the recording capacity is added, and the presence of securing the required recording capacity is decided, and in the head address incapable of adopting the default value, the zone table stored in the memory is adopted, and the recording capacity is reduced, and the recording capacity is increased by other head addresses, and reduced much is compensated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive adopting the MCAV system, and more particularly to a disk drive capable of setting a recording area in accordance with a combination of heads and recording media in a disk drive having a plurality of heads. .

[0002]

2. Description of the Related Art In conventional disk devices such as magnetic disks and optical disks, CAV (Constant Angular Velocity) that keeps the rotational angular velocity constant regardless of the radial position of the disk.
The method was adopted. In this case, the number of sectors is the same for all tracks regardless of the radial position, and therefore,
The recording density decreases as going outward in the radial direction. However, in recent years, in order to increase the recording capacity of the entire disk, the data recording area is divided into a plurality of zones according to the radial position, and the number of sectors per rotation from the inner peripheral side to the outer peripheral side of the disk is increased. The so-called M (Modified) CAV method, which is increased for each zone, has been adopted. In the MCAV system, a common angular velocity is set for all the zones, and the angular velocity increases in each zone as it goes radially outward.

[0003] In a conventional MCAV disk device,
Regarding the configuration of the number of sectors in each zone, a standard zone table is prepared as a default value for the entire disk device, and the characteristics and tolerances of the head and medium to be used are determined at the stage of preliminary evaluation for individual types of disk devices. Examine and calculate possible recording densities. For example, FIG.
A zone table with default values as shown in is prepared.

In the example of FIG. 4, the area on the medium of the disk drive is divided into seven zones according to the radial position. 7
The area in the disk is divided so that the recording density (BPI) in each of the zones is the same between the zones. That is, the same BPI is adopted whether the radial position on the medium is the outer zone or the inner zone. However, within each zone, the recording density changes according to the radial position as shown.

[0005] A certain margin is required between the recording density of a signal actually recorded on a medium and the recording density at which a head can record / reproduce a signal without error in order to ensure reliability. For example, taking the outermost zone as an example, the h position, which is the track position on the outermost circumference side of the zone, has the lowest recording density, so the signal margin is high, and g at the center of the zone is high.
The next highest margin and the lowest margin at the position are the f positions on the innermost peripheral side where the recording density is the highest. Here, if the recording / reproducing head can record / reproduce a signal without error in the disk device in question, and the recording density including the margin is point d, the recording density is calculated according to this standard zone table which is a default value. Should be determined. However, if the possible recording density is point c based on the signal characteristics of the recording / reproducing head, a margin can be secured at the h position, but the margin is insufficient at the f position. In this case, instead of the standard zone table, c
A zone table having a point as the innermost recording density is newly selected. In this case, a desired recording capacity may not be secured.

[0006]

In the conventional MCAV type disk device, the characteristic tolerances of the head and the medium cannot be completely absorbed, so that if a standard zone table cannot be adopted, a desired recording capacity cannot be secured. There's a problem. In this case, although the respective characteristics of the recording / reproducing head and the medium are within the tolerance, this problem becomes remarkable especially when a combination of a head and a medium having low characteristics occurs. According to the present invention, in order to absorb a characteristic tolerance of a recording / reproducing head and a medium in a disk device, a zone table is changed in accordance with a combination characteristic of each head and a medium inside the disk device, thereby recording on the disk device. The purpose is to secure capacity and reliability.

[0007]

According to the present invention, there is provided a disk apparatus comprising: a recording medium having a plurality of recording areas; and a plurality of recording / reproducing heads respectively corresponding to the recording areas. The recording density is selected for each recording area corresponding to the reproducing head.

According to the method of determining a recording area of a disk device of the present invention, a recording medium having a plurality of recording areas and a plurality of recording / reproducing heads respectively corresponding to the recording areas are recorded. In the method for determining a recording capacity, for each combination of a recording / reproducing head and a recording area, a step of measuring a recording density at which recording / reproducing can be performed by the recording / reproducing head; Determining the recording capacity of the recording area.

According to the disk device of the present invention and the method for determining the recording capacity of the recording area thereof, the recording capacity can be selected for each recording area according to the combination characteristics of the head and the recording medium.
A disk device having a desired recording capacity can be easily obtained irrespective of variations in the characteristics of the recording / reproducing head and the recording medium.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings based on embodiments of the present invention. FIG.
FIG. 2 is a schematic perspective view showing an internal configuration of a recording / reproducing head and a recording medium in the disk device of the present invention. In FIG. 1, a disk device 10 of the present embodiment is configured as a hard disk device, and includes a plurality of (six) magnetic recording media 12 accommodated in a frame, and
Of the magnetic recording medium 12 for recording / reproducing on the recording surface of the corresponding magnetic recording medium 12.
) Recording / reproducing heads and a driving device 16 for driving each recording / reproducing head. The driving device 16
It is controlled by a controller (not shown). The controller has a built-in ROM. In the ROM, the recording capacities on the front surface and the back surface of each magnetic recording medium 12 forming one recording area correspond to the respective head addresses 0 to 9 of the recording / reproducing head 14. Stored corresponding to the address.

The recording capacity in each recording area is determined as follows during a test when the magnetic disk drive is completed according to the method of the embodiment of the present invention. FIG. 2 is a flowchart showing a process for determining a recording capacity for each recording area. In the present embodiment, the optimum zone table is determined for each head address by this processing.

First, at step S2, a head address 0 corresponding to the first recording area is selected. Subsequently, in step S3, the recording / reproducing head of head address 0 and the first
A margin test is performed by examining the recording / reproducing characteristics of the signal according to the combination of the recording areas. In step S4, the result of the margin test is examined, and the combination of the recording / reproducing head at head address 0 and the first recording area is determined as follows.
When a standard zone table which is a default value is adopted, it is determined whether or not a signal margin can be secured. As a result, if the necessary margin cannot be secured, the process proceeds to step S5, and the recording density is reduced from the default value. If the result of step S4 shows that a standard margin has been secured, the process proceeds to step S6, and a default value is adopted. If a margin equal to or higher than the standard is secured in step S4, the process proceeds to step S7, and the recording density is increased from the default value. This result is stored in the memory, for example, as a zone table selectable at head address 0, or as a combination of recording density and recording capacity.

Subsequently, the process proceeds to step S8, and since it is not the end of all the heads, the process proceeds to step S11, where 1 is added to the head address 0 to select the head address 1, and the process returns to step S2. Hereinafter, similar processing is performed for the head address 1, and a zone table selectable by the head address 1 is stored in the memory. Similarly, the same processing is sequentially performed at the head addresses 2 to 9 and the result is similarly stored in the memory.

When the processing for all head addresses is completed, the process proceeds to step S9, where the recording capacities stored for all head addresses are added, and it is determined whether or not a desired recording capacity has been secured. In this case, if the combination characteristics of the head and the storage area at each head address are all good, a standard default value is adopted for all head addresses. If a standard default value cannot be adopted for one or more head addresses, a zone table stored in a memory is adopted for that head address, and the recording capacity is reduced. In this case, for the other head addresses, an increase in the recording capacity for compensating the reduction by referring to the memory is adopted.

A specific example of the determination of the necessity of reducing or increasing the recording capacity will be described for a disk device having four heads, that is, a disk device having head addresses 0 to 3. At a certain head address, if the state value at which the recording density matches the default value is 0, the state value at which the margin cannot be secured unless the recording density is lowered is -1, and the state value at which the margin can be secured even at a higher recording density is +1. , All four head addresses belong to any one of these status values. The initial state value of the entire head is 0 + 0 + 0 + 0 = 0, assuming that the capacity of the default value is secured for each head address. As a result of the characteristic test, if the sum of the state values of each head address is 0 or more, the disk device has a desired recording capacity.

Here, if the result of the characteristic test is, for example, that the status values of the respective head addresses 0 to 3 are 0, -1, +1 and 0, respectively, the overall status value is 0-1 + 1 + 0 = 0,
A desired recording capacity can be secured. As a disk device,
The result of the inspection is 0 + 1 + 0 + 1 = 2 or -1 + 1
As in the case of + 1 + 0 = 1, the sum of the state values only needs to be 1 or more. In the former case, all the head addresses are set to the default values and the state of 0 is selected. In the latter case,
The recording density of the head address 0 is reduced, the recording density is increased only for the head address having a higher margin, either the head address 1 or 2, and the other is set to 0. If the sum of the status values of the respective head addresses is negative, the disk device cannot secure the desired recording capacity, and is therefore rejected as a defective product without sending it to the next inspection step. The zone table determined for each head address is written into the ROM, and thereafter used as a unique value of the disk device.

FIG. 2 is a graph showing a zone table used for each head address shown in the above specific example.
In this example, for the adopted zone table, x,
Three types of y and z are prepared. The zone table y, which is a default value, is an initial value set for each head address. In this case, the possible recording density including the margin is d. That is, if the recording density is equal to or lower than the level d, the head can record / reproduce according to the initial value. Here, if recording / reproduction cannot be performed unless the head has the recording density c or less due to the combination characteristics of the head and the medium, the zone table z for low recording density is adopted at the head address. Conversely, if the head is capable of recording / reproducing up to the recording density e due to the combined characteristics of the head and the recording medium, the high recording density zone table x can be employed at the head address.

In this embodiment, an example in which three types of zone tables are provided has been described. However, depending on the combination characteristics of the head and the medium, the number of recording / reproducing heads, etc.
More or more zone tables can be provided.

In the disk device and the recording area determination method of the above embodiment, a configuration is adopted in which the recording area is selected for each head address in accordance with the combination characteristics of the head and the recording medium. Even if there is a variation in the characteristics of each of the above, this can be absorbed by the entire disk device, so that a desired recording capacity can be easily obtained and the yield of the disk device can be improved.

Although the present invention has been described based on the preferred embodiment, the method of determining the recording capacity of the disk device and the recording area of the present invention is not limited to the configuration of the above embodiment. Instead, various modifications and changes made to the configuration of the above embodiment are also included in the scope of the present invention.

[0021]

As described above, according to the disk device of the present invention, a desired recording capacity can be secured with high reliability even if the combination characteristics of the recording / reproducing head and the recording area vary. Can increase the production yield.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing the configuration of a disk device according to an embodiment of the present invention.

FIG. 2 is a flowchart of a process adopted in the embodiment of FIG. 1;

FIG. 3 is a graph illustrating a zone table employed in the method of the present invention.

FIG. 4 is a graph showing a zone table used in a conventional disk device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Disk device 12 Magnetic recording medium 14 Recording / playback head 16 Drive

Claims (4)

[Claims] 1. A disk device comprising a recording medium having a plurality of recording areas and a plurality of recording / reproducing heads respectively corresponding to the recording areas, wherein recording is performed for each recording area corresponding to each of the recording / reproducing heads. A disk device characterized by selecting a density. 2. The disk device according to claim 1, wherein a plurality of zones are provided in each of the recording areas, and recording / reproducing of the MCAV system is performed. 3. The disk device according to claim 1, further comprising a ROM for storing data relating to a recording density of each recording area. 4. A method for determining a recording capacity of a recording area of a disk device including a recording medium having a plurality of recording areas and a plurality of recording / reproducing heads respectively corresponding to the recording areas, comprising: Measuring a recording density at which recording / reproducing can be performed by a recording / reproducing head for each combination of recording areas; and determining a recording capacity of a recording area corresponding to each recording / reproducing head according to the measurement result. A method for determining a recording area of a disk device.