JPH02302974A - Head positioning controller for data recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent the positioning control of a head from being made unstable due to a magnetic noise to accompany a write action by inhibiting the transfer of a servo signal from a servo head at the time of the write action of a data head adjacent to the servo head and using the servo signal stored before the write action. CONSTITUTION:A servo means 16 generates a signal for head positioning control from the servo data on a servo surface 10a read with a servo head 12 and the servo data on a data surface 10b read with data heads 13a-13c. A memory means 27 stores the servo data on the servo surface 10a read from the servo head 12. A switching means 17 reads the servo data on the servo surface 10a before the execution of a write mode from the memory means 27 and transfers the data to the servo means 16 when the data head 13c adjacent to the servo head 12 is in the write mode. In such a case, at the time of the write action of the data head 13c adjacent to the servo head 12, the use of the servo data on the servo surface 10a is inhibited. Thus, the positioning control of the head can be prevented from being made unstable due to the magnetic noise to accompany the write action.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a head positioning control device for a data recording/reproducing apparatus that performs head positioning control based on servo data.

(Prior Art) Conventionally, in a hard disk drive (HDD), as a servo method for controlling head positioning, both servo surface servo data recorded on the servo surface of a recording medium and data surface servo data recorded on the data surface are used. A combined servo system has been developed that utilizes In the combination servo method, a seek control mode (speed control mode) in which the head seeks to the target track based on servo surface servo data is executed, and a position control mode (position control mode) in which the head is positioned at the center of the target track is executed. ) is executed based on the servo data on the servo surface and the data surface.

Incidentally, an HDD is provided with a servo head for reading servo data from the servo surface and a data head corresponding to each data surface. When the data head is positioned at a target position (target track) on the data surface, it executes reading/writing of normal data other than servo data. On the other hand, when the data head is in position control mode,
An operation is performed to read data surface servo data (for example, sector servo data) from the data surface.

When the data head is reading/writing, the seek operation is stopped, but the servo continues reading servo data from the servo surface. In this case, when the data head adjacent to the servo head is performing a write operation, magnetic noise accompanying the write operation may be induced into the servo head, and the servo data read by the servo head may be affected. The magnetic noise may have an adverse effect.

(Problem to be solved by the invention) In the conventional combination servo system, when in the lie mode,
When a data head adjacent to a servo head performs a write operation, magnetic noise accompanying the write operation may have an adverse effect on servo data read by the servo head. For this reason, there is a drawback that the positioning control of the head relative to the target position becomes unstable.

An object of the present invention is to prevent a situation in which head positioning control becomes unstable due to magnetic noise generated in the write operation of the data spatula I adjacent to the →noichi head in the combined servo system. An object of the present invention is to provide a head positioning control device for a data recording/reproducing device that can prevent the above problems.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention provides a head positioning control device of a servo type that uses a servo-to-servo type and a data-to-servo type.
servo means for generating a head positioning control signal from servo surface servo data read by the servo head and data surface servo data read by the data head;
When a memory means for storing servo surface servo data read from the servo head and a data head adjacent to the servo head are in a write mode, the servo surface servo data before execution of the write mode is read from the memory means and transferred to the servo means. This device is equipped with a switching means for

With this configuration, when a data head adjacent to a servo head performs a write operation, the use of servo surface servo data affected by magnetic noise accompanying the write operation is prohibited, and the head is written based on normal servo surface servo data. Positioning control operations can be performed.

(Example) The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an HDD head positioning control device according to the same embodiment.

As shown in FIG. 1, in an HDD, a plurality of recording media 10
It is attached to the spindle mechanism 11, and rotates by the driving force of the spindle mechanism 11 during read/write. The recording medium 10 is provided with a servo surface 10a and a data surface 10b dedicated to servo data recorded in advance. On the data surface 1-[1b, in addition to the data section in which normal data is recorded, a servo data section in which data surface servo data (sector servo data) is recorded in advance is provided, for example, in the gap section of each sector. There is. Servo surface 1
Each servo data of 0a and data surface 10b is transmitted to the corresponding servo head 12 and data heads 13a to 13a, respectively.
Leaded by 3c. The servo head 12 and the data heads 13a to 13c are mounted on a carriage 14, and are configured to seek in the radial direction of the recording medium IO by movement of the carriage 14. The carriage 14 is moved by a carriage drive mechanism 15 whose driving source is, for example, a voice coil motor.

The HDD is provided with a servo circuit 16 for positioning each data head 13a to 13e to a target track on the data surface tob. The servo system circuit 16 controls the carriage drive mechanism 15 based on the servo surface servo data read from the servo surface Oa, and controls the carriage 1
4. Execute seek control mode. Further, the servo system circuit 16 controls the carriage drive mechanism 15 based on the servo surface servo data and the data surface servo data read from the data surface 10b, and executes the position control mode of the carriage 14.

In this embodiment, the servo surface servo data read from the servo head 12 is transferred to the servo system circuit 16 via the switching circuit 17. The switching circuit 17 is
Based on both the write mode signal (write gate) WM output from the disk controller (HDC) 18 and the head selection signal H3 specifying the data head 13c adjacent to the servo head 12, the servo surface servo data before the write mode is This circuit outputs the signal to the servo system circuit 16. The HDC 18 inputs and outputs various interface signals and read/write data necessary for controlling the operation of the HDD.

Specifically, the switching circuit 17 includes switch circuits 20 to 24, an AND circuit 25, and an inverter 26, as shown in FIG. 2, for example. The switch circuit 20 responds to the output signal of the logic level rHJ from the inverter 26,
Servo surface servo data (analog servo signal) SS read by the servo head 12 is transferred to the servo system circuit 16. The switch circuit 21 transmits the servo signal SS or the data surface servo signal DS output from the D/A conversion circuit 28 of the servo data processing circuit 27 to the servo system according to the output signal of logic level "H" from the AND circuit 25. circuit 1
Transfer to 6.

Furthermore, the switch circuit 22 transfers the data surface servo signal DS output from the D/A conversion circuit 29 of the servo data processing circuit 27 to the servo system circuit 16 in accordance with the output signal of logic level rHJ from the inverter 26. .

The servo data processing circuit 27 includes a D/A conversion circuit 28゜2.
9, a microprocessor (CPU) 30 and an A/D conversion circuit 31. The servo data processing circuit 27 temporarily stores the servo signal SS output from the switch circuit 23 or the servo signal DS output from the switch circuit 24 in the state of digital data, and converts this data to the D/A conversion circuit 28 or 29. Convert to analog signal and output.

Next, the operation of this embodiment will be explained. First, when a target track (target cylinder) on the data surface 10b to be read/written is specified by the host computer, seek control of the corresponding data heads 13a to 13c is started. In the seek control mode, the servo system circuit 16 controls the servo head 12 to seek to a position corresponding to the target track based on the servo surface servo signal SS read by the servo head 12. That is, the servo system circuit IC controls the carriage drive mechanism 15 to move the carriage 14 in the radial direction of the recording medium 10 at a predetermined speed. By this movement of the carriage 14, the servo head 12 seeks to a target position corresponding to the target track. Data head L3a'-13c is servo head 1
2 and seeks to the specified target track on the data surface 10b.

In this case, as shown in FIG.
is not output, the output signal of the AND circuit 25 is at the logic level rLJ. Therefore, the output signal of the inverter 26 becomes the logic level rHJ, and the switch circuit 20
．． 22 is turned on. As a result, the switch circuit 2
0 transfers the servo signal SS from the servo head 12 to the servo system circuit 16. On the other hand, when seeking to the target track, a shift is made to a position control mode in which the data heads 13a-13c are positioned at the center of the target track. In the position control mode, as shown in FIG. 2, the switch circuit 24 is turned on by the control signal C2, and the data head 13
The data plane servo (number g DS) read from a-13e is transferred to the servo data processing circuit 27.

In the servo data processing circuit 27, the servo signal S is converted into digital data by the A/D conversion circuit 31 and temporarily stored by the CPU 30.

The CPU 30 outputs the stored digital data to the D/A conversion circuit 29. The D/A conversion circuit 29 converts digital data into an analog servo signal DS to the switch circuit 2.
Output to 2. Since the switch circuit 22 is in the on state, it transfers the servo signal DS to the servo system circuit 16.

Here, it is assumed that the data head 13c adjacent to the servo head 12 is positioned at a target track on the data surface 10b by the servo system circuit (6) and set to a write mode in which data is written.

That is, as shown in FIG.
5 is output. The output signal of the AND circuit 25 has a logic level rHJ. Therefore, the output signal of the inverter 26 becomes the logic level rLJ, and the switch circuit 20.22 is turned off. As a result, the switch circuit 20 prohibits the transfer of the servo signal SS from the servo head 12. Similarly, the switch circuit 22 prohibits the transfer of the servo signal DS from the D/A conversion circuit 29.

On the other hand, since the output signal of the AND circuit 25 is at the logic level "H", the switch circuit 21 is turned on. Furthermore, the switch circuit 23 is turned on by the control signal C1, and the servo surface servo signal SS read from the servo head 12 is transferred to the servo data processing circuit 27. Here, the control signals C1 and C2 are, for example, interface signals transferred from HDCl and 8 or control signals output from the control circuit of the HDD. The servo signal SS from the switch circuit 23 is converted into digital data by the A/D conversion circuit 31 and output to the CPU 30. Here, the control signal C1 is output according to the write mode signal WM. Therefore, the CPU 30 stores data corresponding to the servo signal SS before the selected head 13c executes the write operation.

The data head 13c executes a data write operation on the positioned target track. During execution of this write operation, the CPU 30 outputs a servo signal SS necessary for the position control mode to the switch circuit 21 through the D/A conversion circuit 28. Since the switch circuit 21 is in the on state, the servo signal SS from the D/A conversion circuit 28 is transferred to the servo system circuit 16.

Similarly, the CPU 30 sends the servo signal DS necessary for the position control mode to the switch circuit 21 through the D/A conversion circuit 28.
Output to.

In this way, when the data head 13e adjacent to the servo head 12 is in the write mode, the data head 13c
Servo signal SS stored before execution of write operation by
is switched to a servo signal output from the servo head 12 during the write operation, and is transferred to the servo system circuit 16. Therefore, when magnetic noise due to the write operation of the adjacent data head 13c is induced into the servo head 12, the servo signal SS affected by the magnetic noise is
It is possible to prevent a situation where the data is transferred to the servo system circuit 16. As a result, the adjacent data head 13
During the write operation in c., a reliable head positioning control operation can be performed using the normal servo signal SS stored before execution of the write operation.

FIG. 3 is an application example of the HDD 40 of the same embodiment having a function of changing the number of sectors in the disk format. The HDD 40 is provided with a command decoder 41 that decodes the sector servo write command output from the HDCl 8 and a sector number setting circuit 42.

As described above, in the data surface servo method, sector servo data is recorded in a part of each sector formed by, for example, a track format.

For this reason, conventionally, the number of sectors is fixed when the HDD 40 is shipped as a product, and it has been impossible for the user to arbitrarily set the number of sectors.

Therefore, a sector number setting circuit 42 is provided, and it becomes possible to arbitrarily set the number of sectors in the track format from the outside. Furthermore, the command decoder 41 decodes the sector servo write command transferred from the HD C1B. The instruction format of the command consists of a 4-bit instruction code and an 8-bit permission or start parameter, as shown in FIG. 4(a), for example. For example, the command decoding unit 41 decodes a command as shown in FIG. 5(b) to indicate permission for sector servo writing, and in the case of a command as shown in FIG. It is interpreted as . H
The DD 40 executes a write operation of sector servo data according to the number of sectors set by the sector number setting circuit 42 in response to a command from the HD C 18. As a result, it becomes possible to arbitrarily set the number of sectors in which sector servo data are recorded in the track format.

[Effects of the Invention] As detailed above, according to the present invention, in a combination servo type head positioning control device, the transfer of servo signals from the servo head is prohibited during the write operation of the data head adjacent to the servo head. , uses the servo signal stored before the write operation. As a result, it is possible to prevent the head positioning control from becoming unstable due to magnetic noise accompanying the write operation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a head positioning control device according to an embodiment of the present invention, FIG. 2 is a block diagram showing a specific configuration of a switching circuit of the same embodiment, and FIGS. 3 and 4 are respectively FIG. 3 is a conceptual diagram for explaining an application example of the same embodiment. Ru

Claims (1)

[Scope of Claims] A head of a data recording/reproducing device that positions the head at a target position on a recording medium based on servo surface servo data recorded on a servo surface of a recording medium and data surface servo data recorded on a data surface. In the positioning control device, a servo means for generating a head positioning control signal from the servo surface servo data read by the servo head in the head and the data surface servo data read by the data head; a memory means for storing the servo surface servo data to be read; when the data head adjacent to the servo head is in a write mode, reading the servo surface servo data before execution of the write mode from the memory means; A data recording and reproducing device characterized in that it comprises a switching means for transferring data to the servo means, and a positioning control means for positioning the head at the target position based on the head positioning control signal output from the servo means. Equipment head positioning control device.