JPH0896520A - Data recording/reproducing device and its access method - Google Patents

Abstract

PURPOSE: To realize access control when a fault sector exists without using sector fault information recorded on an ID area and to realize sector constitution without the ID area as a result. CONSTITUTION: The sector fault information for identifying the fault sector in which a fault exists among plural data sectors contained in respective tracks is stored in a sector buffer 11a of an HDC 11. The HDC 11 reads out the sector fault information corresponding to a target track before the access is executed to discriminate the fault condition of the data sector of an access object. By the discriminated result, the HDC 11 executes a control switching the access to a substitutive sector provided on the track or the control skipping the fault sector when the data sector of the access object is the fault sector.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording / reproducing apparatus, such as a hard disk device, provided with access control means when a defective sector exists on the disk.

[0002]

2. Description of the Related Art Conventionally, in a data recording / reproducing apparatus such as a hard disk device (HDD), data is recorded / reproduced by a head on a disk which is a recording medium. The disk has a format structure in which a large number of concentric tracks are formed and each track is divided into a plurality of sectors.

The HDD is provided with a disk controller (HDC) which constitutes an interface with a host system (computer). The HDC controls access to the disk in sector units in response to an access request from the host system.

In the HDD, servo areas are provided at predetermined intervals in the circumferential direction on the disk. In the servo area, servo information for positioning the head on a target track at the time of access is recorded.

Here, CDR (constant de)
In the HDD of the “nsity recording” system,
As shown in FIG. 5, the track format of the disk is configured to include a predetermined number of sectors (referred to as data sectors) A to C between servo areas SA at predetermined intervals. In the CDR system, a large number of tracks are divided into a plurality of zones, and the sectors are configured so that the recording densities are substantially the same in each zone. Therefore, the position of the servo area SA is the same in each track, but the number of sectors and the sector arrangement are different for each zone. In the specific example shown in FIG. 5, the first half of the data sectors A and B and the data sector C are formed between the servo areas SA.

Each data sector is composed of an ID area 50 and a user data area 51, which are roughly called a header section. In the ID area 50, the cylinder (track) number,
ID information including sector position information including a head number and a sector number and split (split counter) information in the CDR system is recorded. The split information is information for detecting a division position of a sector including a data sector separated like the data sector C.

The HDC determines whether or not the data sector is the target sector to be accessed based on the ID information read by the head at the time of executing the access, and if it is the target sector, the data read / write processing is performed. To execute.

By the way, in the above-mentioned disk track format, a method has been proposed in which the ID area 50 is eliminated from each data sector in order to increase the density of the disk. In this method, the sector information corresponding to the sector position information in the ID information is stored in the servo area S.
It is assumed that the configuration is provided in A and the split information is stored in the sector buffer of HDC.

The servo area SA is, as shown in FIG.
AGC area 60, S / I pattern area 61, cylinder code area 62, and burst data area 64
Have. In the S / I pattern area 61, a sector / index pattern for generating a servo sector pulse (SSP) or a servo index pulse is recorded. The servo sector pulse (SSP) is a pulse for detecting the servo area SA. The servo index pulse is a pulse that serves as a reference point of the cylinder CL, and is a pulse that is output only at a specific position (servo area SA).

In the cylinder code area 62, a cylinder address (track number) used for speed control for moving the head to a target cylinder (target track) in head positioning control is recorded. In the burst data area 64, burst data (position signal) used for position control for positioning the head at the center of the target cylinder is recorded.

In such a servo area SA, for example, an area 63 in which sector information is recorded is provided between the cylinder code area 62 and the burst data area 64. The sector information is an area number for identifying each servo area SA (servo sector). The sector buffer of the HDC stores a management table indicating a sector arrangement configuration for each servo sector in the CDR system, and the sector arrangement configuration corresponding to the sector information is referred to from this management table. The data sector pulse (DSP) for detecting each data sector is generated by the sector pulse generation circuit based on the sector information.

With such a method, it seems possible to realize a sector structure without the ID area 50.
However, if the data sector is defective,
Sector defect information (defect information) in the ID area 50
Should be recorded in. The HDC, based on the sector defect information when accessing the ID area 50,
The control for switching the access to the alternative sector or the control for skipping (skipping) the defective sector is executed.

[0013]

In the conventional CDR format disc format, IDs are written from each data sector.
A method has been proposed in which a sector structure having no area is realized to increase the recording density of a disc. In such a method, it is assumed that the position information of the sector is obtained from the sector information recorded in the servo area and the split information is stored in the sector buffer. However, when there is a defect in the data sector, it is necessary to record the sector defect information in the ID area. Therefore, in the sector configuration having no ID area, there is a problem that access control cannot be performed when a defective sector exists. In addition, even if the ID area is provided, if the ID area itself has a defect, there is a problem that information regarding the existence of the defective sector or the position of the substitute sector cannot be accurately read.

An object of the present invention is to surely realize access control when a defective sector exists without using sector defect information to be recorded in the ID area, and as a result, to realize a sector structure having no ID area. It is to provide a data recording / reproducing apparatus capable of performing the above.

[0015]

The present invention is based on, for example, CDR.
In a HDD of the method, sector defect information for identifying a defective sector among a plurality of data sectors included in each track is stored in a memory means such as a sector buffer of HDC, and based on the sector defect information at the time of access. The data recording / reproducing apparatus is provided with a discriminating unit for discriminating a defective state of the data sector to be accessed. The HDC stops access to the defective data sector based on the sector defect information, and switches the access to an alternative sector provided in each track or skips the defective sector.

[0016]

According to the present invention, sector defect information for identifying a defective sector having a defect among a plurality of data sectors included in each track is stored in a memory means such as a sector buffer of the HDC. Before executing the access, the HDC reads the sector defect information corresponding to the target track to determine the defect state of the data sector to be accessed. As a result of this determination, the HDC executes control for switching access to the alternative sector provided on the track or control for skipping if the data sector to be accessed is a defective sector. By this, the ID of the data sector
Access control is realized when a defective sector exists without recording sector defect information in the area, and as a result, I
A sector structure having no D area can be realized.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a hard disk drive (HD
D) is a block diagram showing the main part, FIG. 2 is a conceptual diagram for explaining the storage contents of the sector buffer according to the embodiment, and FIG. 3 is an example of a track format for explaining the operation of the embodiment. Conceptual diagram, FIG. 4 is a flow chart for explaining the operation of the embodiment. (Structure of HDD) The HDD of the embodiment is a device that adopts a CDR type disk format (see FIG. 3) and has a disk 1 having a sector structure in which an ID area is removed from each data sector. The disk 1 is driven to rotate at a high speed by the spindle motor 2, and in this embodiment, the number is one for convenience. The spindle motor 2 is driven by a drive current supplied by a motor driver 3.

The HDD is a head 4 and a head 4 as constituent elements for recording and reproducing data on the disk 1.
Has a head actuator 5 for holding and positioning, a voice coil motor (VCM) 6 for driving the head actuator 5, and a VCM driver 7.

The head actuator 5 is a rotary type actuator, and moves the head 4 in the radial direction of the disk 1 by the driving force of the VCM 6. VCM driver 7
Is a VCM 6 according to positioning control by a servo controller 9 and a microprocessor (CPU) 10 described later.
Drive current is supplied to.

The read / write circuit 8 is a signal processing circuit for processing data read / written by the head 4, and processes user data to be recorded / reproduced in the data sector and servo information read from the servo area SA. That is, the read / write circuit 8 transfers N from the HDC (disk controller) 11 in processing user data.
Write data of RZ code (write current)
And is supplied to the head 4. Further, the read data read by the head 4 is converted into reproduced data of NRZ code and transferred to the HDC 11.

On the other hand, the servo controller 9 performs read / write
Burst data (position signal) and cylinder code are extracted from the servo information reproduced by the write circuit 8, and the CPU
Output to 10. The servo controller 9 also has a data sector pulse generation circuit that generates a data sector pulse DSP for detecting a data sector.

The CPU 10 executes the positioning control of the head 4 according to the command from the HDC 11 and executes the read / write processing. That is, the CPU 10 uses the cylinder code from the servo controller 9 to drive the head 4
Speed control is performed, and the position control of the head 4 is performed using burst data.

The HDC 11 constitutes an interface between the host system and the HDD and controls the transfer of read / write data. The HDC 11 has a sector buffer 11a.
Has a buffer memory called as, and temporarily stores read / write data. In addition, as shown in FIG.
The HDC 11 has an alternative management table 20, split information 21, and a sector defect information table 2 according to the embodiment.
2 is stored in the sector buffer 11a. In addition, HDC
Reference numeral 11 executes address conversion processing for converting a logical address from the host system into a physical address. The physical address is an address including a head number, a zone number, a cylinder number, a sector number, etc. for accessing a data sector when reading / writing data from / to the disk 1. As will be described later, the HDC 13 of the embodiment executes access switching control or skip processing that uses a spare sector as a substitute sector for a defective sector when a defective sector exists. (Explanation of Track Format) In this embodiment, the disc 1 has a CDR format format.
As shown in FIG. 3, each track is provided with a predetermined number of data sectors 30 between servo areas SA, and each data sector 30 has a sector structure having no ID area. Here, it is assumed that the data sectors 30 with sector numbers 10 to 13 are arranged between the servo areas SA. Further, in this embodiment, each track is provided with a spare sector 31 used as a substitute sector for the defective sector. In the servo area SA, servo information (including sector information) as shown in FIG. 5 is recorded. (Description of Operation) Next, the operation of the embodiment will be described with reference to the flowchart of FIG.

First, when there is an access request from the host system, the HDC 11 executes an address conversion process for specifying an access target (steps S1 and S2). That is, the logical address from the host system is converted into a physical address, and the target track to be accessed and the target data sector are specified.

The HDC 11 has an automatic access function for automatically accessing a data sector corresponding to the number of sectors from the data sector having the leading sector number when the leading sector number and the number of sectors in the target track are set.

Before executing the access to the target track, the HDC 11 checks whether or not there is a defective sector on the target track (step S3). In this inspection, the sector number of the data sector corresponding to the defective sector is searched from the alternative management table 20 stored in the sector buffer 11a in advance.

If a defective sector exists in the target track as a result of this inspection, the HDC 11 sets flag information for identifying the defective sector in the sector defect information table 22 provided in the sector buffer 11a (step S4). . As shown in FIG. 2B, the sector defect information table 22 is a table in which flag information (00 or FF) is set for each sector number of each data sector in the target track. The flag information (FF) indicates that the sector is defective, and the flag information (00) indicates that the sector is normal.

Further, the HDC 11 sets a pointer for accessing the sector defect information table 22 before executing the access. This pointer is for designating the address corresponding to the head sector number of the access target.

Next, the HDC 11 sets the head sector number and starts access to the target track (step S5). Here, the head 4 is positioned on the target track by the positioning control of the servo controller 9 and the CPU 10 shown in FIG. For this behavior,
The description is omitted because it is similar to the positioning control in the conventional HDD.

In the target track, access (read / write processing) to each data sector is executed at the detection timing of the data sector pulse DSP.
The data sector pulse DSP is generated by the sector pulse generation circuit of the servo controller 9 based on the sector information recorded in the servo area SA and the split information 21 stored in the sector buffer 11a.

When the data sector pulse DSP is detected, the HDC 11 accesses the sector defect information table 22 with a pointer and determines whether the data sector having the head sector number is a defective sector (step S6).
S7). Here, the first data sector to be accessed is the sector number (10). The HDC 11 is shown in FIG.
As shown in (B), the flag information corresponding to the sector number (10) is read and the defective sector is determined. Here, since it is the flag information (00), the sector number (1
It is determined that the 0) data sector is a normal sector (NO in step S8).

Therefore, the access operation to the data sector having the head sector number (10) is continued, and the data read / write processing is executed (step S).
9). Further, the sector number is updated, and the access operation to the next data sector is started (step S1).
1). That is, when the next data sector pulse DSP is detected, the HDC 11 executes the above-described defective sector determination processing (steps S6 to S8). Here, since the flag information corresponding to the sector number (11) is (00), the data sector is a normal sector. Therefore,
The access operation to the data sector of sector number (11) is continued (steps S9 and S10).

Here, when the access operation shifts to the data sector of the sector number (12), the HDC 11 determines from the sector defect information table 22 flag information (FF) that it is a defective sector (step S8). YE
S). Based on this determination result, the HDC 11 stops the access operation to the data sector of sector number (12) and switches to the access operation to the alternative sector (step S12). That is, as shown in FIG. 3, the spare sector 31 preset in the target track is used as an alternative sector. This alternative sector is used as the data sector of sector number (12). In this case, HDC11
May be controlled not to switch to the alternative sector, but to skip (skip) the data sector having the sector number (12) which is a defective sector and shift the access to the next data sector.

In this way, the HDC 11 uses the sector defect information table 22 prepared in the sector buffer 11a in response to the detection of the data sector pulse DSP when continuously performing access from the data sector of the head sector number. , The defective sector is discriminated. If it is a defective sector, the access operation to the data sector is stopped and the switching control of the access operation to the alternative sector is executed. This makes it possible to reliably perform access control when there is a defective sector.

Therefore, even if sector defect information is not recorded in the ID area of each data sector as in the prior art, it is possible to realize access control when a defective sector exists. In other words, even if there is a defect in the ID area or the ID area in which the sector defect information is not recorded, it is possible to realize the access control when the defective sector exists.

In the conventional CDR system, the same embodiment is
If the sector information is recorded in the servo area SA and the split information is stored in the sector buffer,
It is possible to realize a sector configuration in which the ID area is eliminated from each data sector.

[0037]

As described above in detail, according to the present invention, I
Access control when a defective sector exists in a data sector can be realized without using sector defect information recorded in the D area. Therefore, it is not necessary to record the sector defect information in the ID area. Further, by applying information corresponding to ID information other than the sector defect information to the sector buffer or the servo area, it is possible to realize a sector structure having no ID area as a result. As a result, a recording capacity corresponding to the ID area can be secured, so that the recording capacity of the disk can be increased and a high recording density can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of a hard disk device (HDD) according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram for explaining stored contents of a sector buffer according to the embodiment.

FIG. 3 is a conceptual diagram showing an example of a track format for explaining the operation of the embodiment.

FIG. 4 is a flowchart for explaining the operation of the embodiment.

FIG. 5 is a conceptual diagram showing a conventional CDR format track format.

[Explanation of symbols]

1 ... Disk, 2 ... Spindle motor, 3 ... Motor driver, 4 ... Head, 5 ... Head actuator, 6 ... Voice coil motor, 7 ... VCM driver, 8 ... Read /
Write circuit, 9 ... Servo controller, 10 ... CPU,
11 ... HDC, 11a ... Sector buffer.

Claims (7)

[Claims] 1. A head for recording / reproducing data, a data sector for recording the data for each track, and a servo area in which servo information for positioning control of the head is recorded, A disk having a predetermined number of data sectors formed between servo areas; memory means for storing sector defect information for identifying a defective sector among the plurality of data sectors included in each track; An access control unit for positioning the target track on the target track to access the designated data sector to execute data read / write processing; and, before executing the access, the sector corresponding to the target track from the memory unit. The defect information is read, and the defect state of the data sector to be accessed is read based on the sector defect information. Data recording and reproducing apparatus characterized by comprising a discriminating means for discriminating. 2. A head for recording / reproducing data, a data sector for recording the data for each track, and a servo area in which servo information for controlling the positioning of the head is recorded. A disk having a predetermined number of data sectors formed between servo areas, a memory unit storing sector defect information for identifying a defective sector among the plurality of data sectors included in each track, and a target track Before the access to the specified data sector is performed, the sector defect information corresponding to the target track is read from the memory means, and the defect state of the data sector to be accessed is determined based on the sector defect information. Discriminating means for positioning the head on the target track and allocating the designated data sector. Access control means for accessing and executing data read / write processing, wherein when the data sector to be accessed is a defective sector by the determination means, the access is temporarily interrupted and switched to the access of the alternative sector. A data recording / reproducing apparatus comprising: an access control unit that executes control. 3. A head for recording / reproducing data, a data sector for recording the data for each track, and a servo area in which servo information for positioning control of the head is recorded, A disk having a predetermined number of data sectors formed between servo areas, a memory unit storing sector defect information for identifying a defective sector among the plurality of data sectors included in each track, and a target track Before the access to the specified data sector is performed, the sector defect information corresponding to the target track is read from the memory means, and the defect state of the data sector to be accessed is determined based on the sector defect information. Discriminating means for positioning the head on the target track and allocating the designated data sector. Access control means for accessing and executing data read / write processing, wherein when the data sector to be accessed is a defective sector by the determining means, the access is temporarily interrupted and the defective sector is skipped. A data recording / reproducing apparatus comprising: an access control unit that executes control. 4. A head for recording / reproducing data, a servo area in which a data sector for recording the data for each track, a substitute sector for a defective sector, and servo information for positioning control of the head are recorded. A disk having a predetermined number of data sectors formed between the servo areas, and sector defect information for identifying a defective sector among the plurality of data sectors included in each track. Before executing the access to the data sector designated by the memory means and the target track, the sector defect information corresponding to the target track is read from the memory means, and the data to be accessed is accessed based on the sector defect information. A discriminating means for discriminating a defective state of the sector; Access means for accessing the data sector to execute data read / write processing, and if the data sector to be accessed is a defective sector based on the determination result of the determination means, access is performed. A data recording / reproducing apparatus comprising: an access control unit that temporarily stops and switches to access to the alternative sector, and executes control to continue access in the case of a normal sector. 5. A head for recording / reproducing data, a data sector for recording the data for each track, a substitute sector for a defective sector, and a servo area in which servo information for controlling the positioning of the head is recorded. A disk having a predetermined number of data sectors formed between the servo areas, and a memory storing sector defect information for identifying a defective sector among the plurality of data sectors included in each track. Means for reading the sector defect information corresponding to the target track from the memory means before executing the access to the specified data sector of the target track, and accessing the data sector to be accessed based on the sector defect information. Discriminating means for discriminating the defect state of the head, positioning the head on the target track, and designating the head. The access control means having an automatic access function for consecutively accessing from a data sector having a leading sector number to a predetermined number of data sectors, wherein the access target is a defective sector based on the determination result of the determination means. Access control means for executing the automatic access function by selecting one of an operation of temporarily suspending access, an operation of executing access to the alternative sector, and an operation of continuing access in the case of a normal sector. A data recording / reproducing device characterized by the above. 6. A head for recording / reproducing data, a servo area in which a data sector for recording the data for each track, a substitute sector for a defective sector, and servo information for positioning control of the head are recorded. A disk having a predetermined number of data sectors formed between the servo areas, and sector defect information for identifying a defective sector among the plurality of data sectors included in each track. A data recording / reproducing apparatus comprising: memory means; and the access control means for positioning the head on a target track to access a designated data sector to execute a data read / write process. Of the target track from the memory means before performing an access to the data sector of A step of reading the corresponding sector defect information; a step of determining the defect state of the data sector to be accessed based on the read sector defect information; and a step of determining the data sector to be accessed based on the determination result. In the case of a defective sector, the access is temporarily stopped and the access is switched to the alternative sector, and in the case of a normal sector, the access is continued. 7. A head for recording / reproducing data, a servo area in which a data sector for recording the data for each track, a substitute sector for a defective sector, and servo information for controlling the positioning of the head are recorded. A disk having a predetermined number of data sectors formed between the servo areas, and sector defect information for identifying a defective sector among the plurality of data sectors included in each track. Data including memory means and the access control means having an automatic access function for positioning the head on a target track and successively accessing from a data sector having a designated start sector number to a predetermined number of data sectors In the recording / reproducing apparatus, before performing access to the specified data sector of the target track, A step of reading the sector defect information corresponding to the target track from the memory means; a step of determining the defect state of the data sector to be accessed based on the read sector defect information; Setting and starting the automatic access function, in the automatic access function, when the access target is a defective sector based on the determination result of the defect state, the operation of temporarily suspending the access, the access of the alternative sector And a step of selecting and executing one of an operation to be executed and an operation to continue the access in the case of a normal sector.