JPH0487075A - Signal recording method of magnetic disk device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a signal recording method for recording signals on a recording medium such as a flexible magnetic disk device or a fixed magnetic disk device.

BACKGROUND OF THE INVENTION Conventionally, this type of magnetic disk drive has been configured to use a rotating magnetic disk as a recording medium, and to record and read signals and data using a magnetic head, which is a transducer. . Information is stored on a magnetic disk by forming recording areas on concentric circles called a plurality of tracks as a regular series of magnetization reversals.

Also, the track is divided into small fan-shaped areas called sectors, and these sectors are the basic units of information storage.

By the way, when recording and reproducing (reading) information, it is necessary for the magnetic head to accurately follow the track. For this purpose, a signal (servo signal) for knowing the following state of the magnetic head is set on the track separately from the information to be recorded, this servo signal is read by the magnetic head, and based on the read result, the magnetic head A method called tracking servo that slightly changes the position of the servo is generally adopted.

One of these tracking servo systems is a sector servo system, in which a servo signal is formed between each sector. In this case, since the servo signal exists between sectors, the servo signal is generated at regular time intervals.

As a result, tracking servo is executed at fixed time intervals according to the detection timing of the servo signal. Therefore, for a servo control system, the period in which a servo signal is generated is one of the important parameters as a design element of the control system.

Problems to be Solved by the Invention However, in the conventional configuration as described above, when attempting to increase the recording capacity using the equal density method, the number of sectors differs between the inner and outer circumferences of the magnetic disk. It is necessary to change the characteristics of the control system for tracking servo. Therefore, there was a problem that the configuration became complicated.

The present invention solves the above-mentioned conventional problems, and aims to provide a signal recording method for a magnetic disk device that can increase the recording capacity using a uniform density method with a simple configuration. This is the purpose.

Means for Solving the Problems In order to achieve the above object, the present invention provides a magnetic disk having tracks formed concentrically with respect to the center of rotation. A servo signal is provided, and the number of sectors arranged between adjacent servo signals is made different between the inner circumference and the outer circumference.

Preferably, the number of sectors is greater at the outer circumference of the track than at the inner circumference so that servo signals can be generated at regular time intervals.

Further, in order to maximize the total recording capacity, it is desirable to make the number of sectors and the data transfer rate of the recording signal different between the inner circumferential portion and the outer circumferential portion.

Therefore, according to the present invention, the plurality of servo signals extending radially from the center of rotation are set to have equal time intervals, so that the time intervals of the servo signals are equal from the inner circumference to the outer circumference, and all tracks The same servo control system can be applied in both.

Furthermore, since the servo signal is provided at each angle, the number of sectors is greater at the outer circumference of the track than at the inner circumference. As a result, the amount of recorded information increases, making it possible to increase the recording capacity per magnetic disk.

Furthermore, by making the number of sectors and the data transfer rate of recording signals different between the inner circumferential portion and the outer a portion, it is possible to maximize the format capacity.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing an example of a magnetic disk recorded using the signal recording method according to the present invention, and FIG. 2 is a partially enlarged view of a track.

In FIG. 1, on the surface of a disk-shaped magnetic disk l,
A plurality of tracks 2 are formed concentrically at regular intervals in the radial direction from the center of rotation. Each track 2 is divided into a plurality of sectors 3 in the circumferential direction.

The tracks 2 are serially numbered from O to N from the outermost circumference toward the center. The outermost one is numbered 0 and the innermost one is numbered N. Furthermore, sectors 3 are numbered sequentially up to the Mth sector, with a certain predetermined position being the first sector.

Further, between each sector 3, a servo signal 4 is formed radially at a constant angle from the rotation center of the magnetic disk 1.

Next, a track format according to the present invention will be explained.

FIG. 3 is a track format diagram of the present invention.

As shown in FIG. 3, the track 2 rotates into servo signals 4 arranged at approximately equal intervals, a block 5 which is an area consisting of a single or multiple sectors 3 between the servo signals 4, and a beginning part and a final part. Due to factors such as fluctuations, the above servo signal 4
and a gap region 6 and a gap region 7 for protecting the block 5.

One of the sectors 3 is I indicating the contents of each information block.
It consists of a D (identification) area 8, a data area 9 that stores information to be recorded, and a gap 10 that separates the two areas, the ID area 8 and the data area 9.

ID area 8 and data area 9 are PL for motor drive.
Although it has further subdivided areas such as a 5YNC (synchronization) area used for synchronization of the L (phase φ locked loop) circuit, their explanation is omitted here as they are not related to the present invention. do.

Tracks 2 on the magnetic disk 1 are numbered from 0th to N'
It is divided into two areas: an outer circumferential area up to the th area and an inner periphery area from the (N'+1)th area to the Nth area. In these two areas, the number of sectors recorded on each track 2 and the data transfer speed of recording signals are recorded differently, so that the total recording capacity stored on the magnetic disk 1, that is, the format capacity is maximized. configured.

Note that the number of divided regions is not limited to two, and can be multiple, but for convenience of explanation, only two cases are illustrated here.

Next, the arrangement of sectors 3 and servo signals 4 in each block 5 divided as described above will be explained using FIGS. 4 and 5.

FIG. 4 is a diagram showing the arrangement of inner sectors and servo signals in the present invention, and FIG. 5 is a diagram showing the arrangement of sectors and servo signals in the outer periphery of the invention.

As shown in FIG. 4, two sectors 31 and 32 are provided between adjacent servo signals 4, and each sector 3
1.32 has a gap area 6, an ID area 8 and a data area 9.

On the other hand, as shown in FIG. 5, there are three sectors 33, 34, and 35 between adjacent servo signals 4 on the outer periphery. Note that the relative linear velocity between the head and the magnetic disk is larger than the number of servo signals 4 included in the inner circumference, so if the data transfer rate is set so that the linear recording density is equal to that of the inner circumference, A large amount of data can be recorded compared to the peripheral part. Therefore, on the outer circumferential side from a specific track 2, a greater number of sectors can be stored between servo signals than on the inner circumference as described above, so the recording capacity can be increased without changing the head or magnetic disk. be able to.

Here, the interval between the servo signals 4 is determined by the angular velocity, and unlike the linear velocity, this angular velocity is constant from the inner circumference to the outer circumference, which makes the above arrangement possible.

Furthermore, in a flexible magnetic disk drive, even if the track number is the same on two sides of the recording medium, the radius is different. Therefore, it is normal that the linear velocities are also different. Therefore, in order to increase the capacity of the magnetic disk, it is desirable to arrange the boundary tracks with different numbers of sectors between the servo signals mentioned above so that the track number becomes larger on the same track with a larger radius. .

Furthermore, when a magnetic disk device exchanges information with an external device, information of a size obtained by dividing a unit amount of information by an integer including 1 is stored in one sector.

FIG. 6 shows measurement data for a 3- and 5-inch flexible magnetic disk device according to the prior art, and FIG. 7 shows measurement data for a 3- and 5-inch flexible magnetic disk device according to the present invention. As is clear from FIGS. 6 and 7, according to the present invention, the recording capacity can be increased to about 125% of the conventional one.

Note that the present invention can be applied even if the size of the unit of information exchanged between the host computer and the magnetic disk device, that is, the block size and the sector size described above, do not match. For example, even if information is exchanged with the host computer in units of 512 bytes,
The present invention can be easily implemented by making two consecutive accesses to a 256-byte sector.

Effects of the Invention Since the present invention is configured as described above, it achieves the following effects.

In the signal recording method of a magnetic disk device according to claim 1, a plurality of servo drives extending radially with respect to the rotation center so as to cross all tracks on a magnetic disk having tracks formed concentrically with respect to the rotation center. Since the number of sectors arranged between adjacent servo signals is different between the inner and outer circumferences, the time intervals of the servo signals are equal from the inner circumference to the outer circumference, making it easy to Depending on the configuration, the same servo control system can be applied to all tracks.

In the signal recording method for a magnetic disk drive according to the second aspect, since the number of sectors is greater at the outer circumference than at the inner circumference of the track, servo signals can be generated at regular time intervals.

In the signal recording method of a magnetic disk device according to claim 3, since the number of sectors and the data transfer rate of the recording signal are made different between the inner circumference and the outer circumference, it is possible to maximize the format capacity. be.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an example of a magnetic disk recorded using a signal recording method according to an embodiment of the present invention, FIG. 2 is a partially enlarged view of the track in FIG. 1, and FIG. 3 is a track of the present invention. Format diagram, FIG. 4 is an arrangement diagram of inner sectors and servo signals in the present invention, FIG. 5 is an arrangement diagram of sectors and servo signals in the outer peripheral part of the invention, and FIG. 6 is a 3.5-inch arrangement according to the conventional technology. FIG. 7 is a diagram of measurement data for a 3.5-inch flexible magnetic disk device according to the present invention. 1... Magnetic disk, 2... Track, 3.31.
33.34.35...Sector, 4...Servo signal,
5...Block, 6.7...Gap area, 8...
- ID area, 9...data area, 10...gap. Figure 1 Figure 2 Name of agent Patent attorney Shigetaka Awano Figure 1

Claims (3)

[Claims] (1) For a magnetic disk having tracks formed concentrically with respect to the center of rotation, a plurality of servo signals are provided that extend radially to the center of rotation across all tracks, and these servo signals are arranged between adjacent servo signals. 1. A signal recording method for a magnetic disk device, characterized in that the number of sectors recorded is different between an inner circumferential portion and an outer circumferential portion. (2) The signal recording method for a magnetic disk device according to claim 1, wherein the number of sectors is greater at the outer circumference of the track than at the inner circumference. (3) Claim 1 characterized in that the number of sectors and the data transfer speed of the recording signal are made different between the inner circumference and the outer circumference.
The signal recording method of the magnetic disk device described above.