JPH11110932A - Servo data checking method and large capacity felxible disk servo writer which executes the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method and the device to simply check the writing of servo data into a large capacity flexible disk. SOLUTION: Recorded position information is read as position signals from the magnetic disk medium, into which servo data are written on every track, compared with the position information of the servo data and error signals are generated. Then, track addresses and sector addresses of the servo data are made into X and Y coordinates, the error signals are made into Z coordinate and position error picture signals are generated by these coordinates and displayed on a display for the checking. Moreover, a servo writer has a checking function using this method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a servo writer for a large-capacity flexible disk, and more particularly to a method for checking written servo data and a servo writer for executing the method.

[0002]

2. Description of the Related Art A flexible disk in which a magnetic disk medium for recording data is housed in a case (that is, a diskette) is well known. In recent years, the capacity of flexible disks has been increased, and the capacity of conventional flexible disks having a storage capacity of 1 to 2 Mbytes has been increased to 128
A disk having a large storage capacity of M bytes has been developed (this flexible disk having a large storage capacity is referred to as a large-capacity flexible disk).

In a large-capacity flexible disk, it is necessary to write servo data (also called a servo pattern) after manufacturing the disk medium. This writing of servo data is called a servo format. Servo format is about 10μ on disk media.
A plurality of (normally 1600) tracks are constructed at a track pitch of m, each track is divided into a plurality of (normally 80) sectors, and position information of the tracks and sectors is written.

An apparatus for performing this servo format on a magnetic disk medium of a large-capacity flexible disk is called a servo writer for a large-capacity flexible disk. A conventional servo writer for a large-capacity flexible disk uses a hard disk drive (H
Using a head carriage with a modified head gimbal assembly used in DD), a magnetic head load / unload mechanism is provided externally to write servo data. A magnetic disk medium to be written is rotatably supported by a spindle via an air bear link. This conventional servo writer can directly write servo data on a magnetic disk medium without a diskette.

Apart from this conventional servo writer, the present inventors have used a head carriage for holding a magnetic head on a large-capacity flexible disk for recording and reproducing data on a magnetic disk medium of a large-capacity flexible disk. Using the linear motion head carriage
A proposal has been made in which the direct-acting head carriage is integrated with an actuator of a servo writer by a connecting rod (Japanese Patent Application No. 132189).

It is necessary to check the servo data after writing the servo data on the magnetic disk medium by the servo writer. Conventionally, after writing servo data on a magnetic disk medium, storing the magnetic disk medium on a diskette and assembling a large-capacity flexible disk, setting the servo data to a device for checking, and using the servo data as a servo pattern signal It reads and checks its phase. That is, a gain curve is obtained as shown in FIG. 3A and a phase curve is obtained as shown in FIG.

As is well known in control theory, the gain G at the phase point (the point where the
Is negative when expressed in decibels (dB), the servo system is unstable; Also, if the phase difference at the gain crossing point (point where the gain intersects the line of 1, ie, 0 (dB)) is larger than 180 °, the servo system is stable, and if it is small, the servo system is unstable.

[0008]

However, it is not sufficient to check the written servo data only by checking the phase described above. The track address (Gray Code) of the servo data and the PES (P
It is necessary to verify the position error signal data. However, checking the track address of the servo data and the PES of the position signal requires skill and is not easy.

Further, as in the prior art, after writing servo data from a servo writer and then checking the servo data with another checking device, the number of steps required to produce a large-capacity flexible disk with a servo format is increased. However, there is a drawback that the number increases.

Accordingly, an object of the present invention is to provide a method of easily checking PES data of a track address and a position signal as a check of written servo data.

A further object of the present invention is to provide a servo writer capable of checking servo data written on a magnetic disk medium in order to reduce the number of steps for producing a large-capacity flexible disk with a servo format. It is to be.

[0012]

According to the present invention, a track is constructed on a magnetic disk medium of a large-capacity flexible disk based on servo data including a track address, a sector address and position information, and each track is divided into a plurality of tracks. In the method of checking servo data written on the magnetic disk medium by dividing the sector into sectors and recording track and sector position information, the position recorded for each of the tracks constructed from the magnetic disk medium is recorded. The information is read as a position signal, the position signal is compared with the position information of the servo data to generate an error signal, the track address and the sector address of the servo data are set to X and Y coordinates, and the error signal is set to the Z axis. Generate a position error image signal as coordinates, and apply the position error image signal to the position error. Displayed as a three-dimensional image on over the display, from the three-dimensional image, the recorded check method of the servo data of a large capacity flexible disc, characterized in that to determine the servo data is obtained.

According to the present invention, a servo data storage unit for storing servo data including a track address, a sector address and position information, and a track is constructed on a magnetic disk medium of a large-capacity flexible disk based on the servo data. A writing unit that divides each track into a plurality of sectors and writes the servo data by recording track and sector position information; and a recording position for each of the tracks constructed from the magnetic disk medium. A reading unit that reads information as a position signal, a signal processing unit that compares the position signal with the position information of the servo data to generate an error signal, and that a track address and a sector address of the servo data are X and Y coordinates, Image signal generation for generating a position error image signal using the error signal as a Z-axis coordinate When the servo writer for a large-capacity flexible disk and having a position error display for displaying the position error image signals as a three-dimensional image is obtained.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

Referring to FIG. 1, a servo writer for a large-capacity flexible disk (hereinafter, simply referred to as a servo writer) according to an embodiment of the present invention shown in FIG. 1 transmits servo data including a track address, a sector address and position information. It has a servo data storage unit 10 for storing and a writing unit for writing servo data.

The writing unit is a magnetic disk medium 11
Motor 12, a motor control circuit 13 for controlling the drive motor 12, a head carriage 15 supporting a magnetic head 14 for writing data to the magnetic disk medium 11, and a carriage drive for driving the head carriage 15. The apparatus includes a device 16, a carriage control circuit 17 for controlling the carriage driving device 16 to control the movement of the head carriage, and a writing circuit 18 for receiving the servo data and supplying the position information to the magnetic head for writing. The driving motor 12 and the carriage driving device 16 are supplied with a driving power supply (represented by PS).

The servo writer further includes a motor control circuit 13, a head carriage 15, and a carriage control circuit 1.
7 and a control circuit 19 for controlling the writing circuit 18. Note that the servo data storage unit 10 and the control circuit 19 can be configured by a CPU 20. Also, C
A keyboard 21 is connected to the PU 20 so that an operator of a servo writer can manually input commands and data.

According to the present invention, the servo writer further has a reading unit for reading information from a magnetic disk medium to check writing of servo data. The read unit is connected to the magnetic head 14 and reads a position information recorded on the magnetic disk medium as a position signal. The read unit 22 compares the position signal from the read circuit 22 with the servo data in the servo data storage unit 10. ,
A signal processing circuit 23 for generating an error signal; an image signal generating circuit 24 for generating a position error image signal using the track address and sector address of the servo data as X and Y coordinates and the error signal as Z axis coordinates; It has a position error display 25 for displaying an error image signal as a three-dimensional image.

The reading circuit 22, the signal processing circuit 24,
The image signal generation circuit 24 and the position error display 25 operate under the control of the control circuit 19 described above.
The signal processing unit 23 and the image signal generating unit 24
20.

Hereinafter, the operation of the present servo writer will be described.

At the time of writing the servo data, when a write command is input by the operator from the keyboard 21, the control circuit 19 reads the servo data from the servo data storage unit 10 and controls the motor control circuit 13 and the carriage control circuit 17. Then, the drive motor 12 is driven to rotate the magnetic disk medium 11 and the position of the head carriage 15 is controlled. At the same time, the position information is supplied to the writing circuit 18 and written to the magnetic disk medium 11 via the magnetic head 14. Thus, a track is constructed on the magnetic disk medium 11 based on the servo data, each track is divided into a plurality of sectors, and the position information of the track and the sector is recorded. That is, the servo data is written. This operation is similar to the operation of the conventional servo writer.

When the writing of the servo data is completed, a writing check operation is started. The start of this check operation is programmed in the control circuit and is automatically performed. Alternatively, the end of writing may be displayed on a monitor display (not shown) so that the operator confirms the end of writing and then inputs a read or check operation start command from the keyboard 21.

When the check operation is started, the control circuit 1
Numeral 9 reads out servo data from the servo data storage unit 10, and reads the motor control circuit 13 and the carriage control circuit 17.
, The drive motor 12 is driven to rotate the magnetic disk medium 11, and the position of the head carriage 15 is controlled. At the same time, a reading instruction is given to the reading circuit 22. Thus, the position information recorded on the magnetic disk medium 11 is read from the magnetic head 14 as a position signal.

This position signal is supplied to a signal processing circuit 23, where it is compared with servo data supplied via a control circuit 19 to generate a difference signal from position information, that is, an error signal. This error signal is supplied to the image signal generation circuit 24 together with the track address and the sector address of the servo data.

The image signal generation circuit 24 receives this,
The track address and the sector address are X and Y coordinates,
A position error image signal having the error signal as a Z-axis coordinate is generated. This position error image signal is displayed on the position error display 25 as a three-dimensional image. A print command can be input from the keyboard 21 as needed, and the printer 26 can print out a three-dimensional image of the position error.

FIG. 2 shows that the servo data is written and checked by the servo writer,
6 is an example of a three-dimensional image of the position error printed out by No. 6. (A) is data on the first surface of the magnetic disk medium, and (b) is data on the second surface, which is the back surface. Since a smaller position error is better, it is desirable for a magnetic disk medium to have less and less irregularities on the image. Thus, the quality of the magnetic disk medium on which the servo data has been written can be easily checked visually by the unevenness on the image.

The position error display 25
Can be used also as the monitor display described above. Further, it is possible to add a configuration in which the signal processing circuit 23 performs signal processing for obtaining a Bode diagram as shown in FIG. 3 and displays the signal on the Bode diagram display 27.

In the above-described embodiment, the configuration in which the check after writing the servo data is performed by the same servo writer has been described. However, the check operation part may be configured as another device. In this case, the servo data may be written to the magnetic disk medium by a conventional servo writer, and then the magnetic disk medium may be set in the other device to perform a check. In this case, although the number of steps is increased, the quality of the magnetic disk medium on which the servo data is written can be easily visually checked as compared with the conventional check.

[0029]

As described above, according to the method of the present invention, the quality of a magnetic disk medium on which servo data has been written can be easily visually checked. Also,
ADVANTAGE OF THE INVENTION According to the servo writer of this invention, since it is not necessary to reset a magnetic disk medium to another apparatus for a check, a check can be performed easily and there exists an effect which can reduce the number of processes and cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a servo writer according to the present invention.

2A and 2B are examples of a three-dimensional image of a position error output by the servo writer of FIG. 1; FIG. 2A shows data on one surface of a magnetic disk medium, and FIG. .

FIG. 3 is an example of a Bode diagram of a large-capacity flexible disk measured after writing servo data with a conventional servo writer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Magnetic disk medium 12 Drive motor 13 Motor control circuit 14 Magnetic head 15 Head carriage 16 Carriage drive device 17 Carriage control circuit 18 Writing circuit 19 Control circuit 20 CPU 21 Keyboard 22 Reading circuit 23 Signal processing circuit 24 Image signal generation circuit 25 Position error Display 26 Printer 27 Bode diagram display

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshinori Tanki 1601 Sakai, Atsugi-shi, Kanagawa Mitsumi Electric Co., Ltd.

Claims (2)

[Claims] 1. A track is constructed on a magnetic disk medium of a large-capacity flexible disk based on servo data including a track address, a sector address and position information, and each track is divided into a plurality of sectors. In a method of checking servo data written on the magnetic disk medium by recording position information, the recorded position information is read out as a position signal for each of the constructed tracks from the magnetic disk medium, and the position information is read. A signal is compared with the position information of the servo data to generate an error signal, a track address and a sector address of the servo data are set to X and Y coordinates, and a position error image signal is set to set the error signal to Z axis coordinates. ,
A servo data check method for a large-capacity flexible disk, comprising displaying the position error image signal as a three-dimensional image on a position error display, and judging recorded servo data from the three-dimensional image. 2. A servo data storage unit for storing servo data including a track address, a sector address and position information, and a track is constructed on a magnetic disk medium of a large-capacity flexible disk based on the servo data. A writing unit for writing the servo data by dividing the number of sectors and recording the position information of the track and the sector, and reading the recorded position information from the magnetic disk medium for each of the constructed tracks as a position signal A read unit, a signal processing unit for comparing the position signal with the position information of the servo data to generate an error signal, a track address and a sector address of the servo data as X and Y coordinates, and the error signal as a Z axis An image signal generator for generating a position error image signal as coordinates, A servo writer for a large capacity flexible disk, comprising: a position error display for displaying an image signal as a three-dimensional image.