JPH0421903A - Recording method for fdd - Google Patents

Abstract

PURPOSE:To enable the recording of a FDD with a high reproducing S/N by seeking a recording/reproducing head from a positioning position in the beginning of a distance corresponding to positioning error to an inner periphery and an outer periphery, and recording a new data at the first positioning position after erasing a former data. CONSTITUTION:The recording/reproducing head is set at a track positioning position 2 and seeked to an inner peripheral seek position 3 for 3mum in the direction of an inner peripheral side 4. The former data is erased by letting a direct current flow to the recording/reproducing head. The head is seeked to an outer peripheral seek position 4 for 6mum in the direction of an outer peripheral side 6. The former data is erased by letting the direct current flow to the recording/reproducing head. Then, the head is seeked to the track positioning position 2 for 3mum in the direction of an inner peripheral side 4. Finally, the new data is recorded by the recording/reproducing head. Thus, the data is reproduced by the above-mentioned recording method and according to a ratio between the former recording data and the new recording data, the S/N can be improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to an FDD (floppy disk device, hereinafter abbreviated).
The present invention relates to a recording method for a PDD having a servo system, and specifically relates to a recording method for a PDD having a servo system.

[Conventional technology]

The storage capacity of FDDs is increasing as portable computers and word processors become more popular.

This increase in storage capacity is achieved not only by increasing the linear recording density in the circumferential direction of the FD (floppy disk), but also by increasing the track density in the radial direction.
The number of tracks per inch (hereinafter omitted) has been achieved.

In such a high track density FDD, a servo system is employed, and the target track is positioned within the positioning error range of the system.

In addition, in devices that employ such a high trunk density, the recording/reproducing track width is, for example, 40 μm, which is significantly 1.5 μm. ＜Small.

For this reason, when using the conventional tunnel erase type magnetic head shown in FIG.
2 must be set to, for example, 10 μm or less, but it has become difficult to provide such a magnetic head by mass production.

Therefore, in the above-mentioned high track density FDD, a single gap write/read head without an erase head is used.

[Problem to be solved by the invention]

However, in an FDD that uses a recording/reproduction-only head that does not have such a tunnel erase type erase head, when a conventional recording method is used, the following occurs.
There is a problem that old data may remain unerased.

As shown in FIG. 3, when a new recording track 16 is overwritten on an old recording track 14 that has already been recorded, an unerased track 20 whose width corresponds to the positioning error 18 of the servo system used in the worst case occurs.

The data of the old recording left on this unerased track 20 is included as noise in the reproduced data of the new recording due to positioning error during reproduction, deteriorating the S/N ratio during reproduction and impairing the reliability of the device. There is a problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording method that does not leave old data unerased and has an excellent reproduction signal-to-noise ratio even when using a single-gap recording/reproduction-only magnetic head.

[Means to solve the problem]

In the present invention, after positioning the recording/reproducing head on a target track, the recording/reproducing head is sought to the inner and outer peripheries from the initial positioning position by a distance corresponding to the positioning error of the servo system, and the target track is located at each position. The above problem is solved by a recording method in which new data is recorded at the original position after erasing the old data in the sector, and the FD has an excellent playback S/N ratio without leaving any old data unerased.
This made it possible to provide the recording method D.

[Effect]

In place of the conventional method of erasing old data by overwriting, in which recording and erasing are performed simultaneously, the present invention employs a recording method in which erasing old data and recording new data are performed separately.

The recording/playback head seeks from the initial positioning position to the inner and outer sides by an amount equivalent to the maximum positioning error expected, and at each seek position, the data of the target sector is sent to the recording/playback head using direct current or Because the data is erased by applying low-frequency alternating current, no old data remains unerased.

The details of the present invention will be explained below based on the drawings and examples.

〔Example〕

FIG. 1 is a conceptual diagram of the track position showing an embodiment of the recording method of the present invention. The example assumes a track density of 540 TI'I, and the inherent positioning error of the servo system is ±3μ.
This is an example in the case of m.

1) Position the recording/reproducing head at track positioning position 2. (a) 2) Seek 3 μm to inner circumferential seek position 6 in four directions on the inner circumferential side. (b) 3) Delete old data by passing DC current through the recording/reproducing head.

4) Seek 6 μm to the outer periphery seek position 4 in 6 directions on the outer periphery side. (C) 5) Delete old data by passing DC current through the recording/reproducing head.

6) Seek 3 μm to track positioning position 2 in four directions on the inner circumferential side. td) 7) Record new data with the record/playback head.

When the data recorded using the above recording method was reproduced and the S/N ratio based on the ratio of the old recorded data to the new recorded data was measured, it showed an excellent S/N ratio of 51 dB.

〔Effect of the invention〕

As mentioned above, as a result of the significant improvement in the SN ratio due to unerased old recorded data, the reliability of the FDD as a device has increased and commercialization has been realized. 7. Furthermore, since the recording method is a method of erasing old data and recording new data separately, recording and erasing can be performed under optimal conditions for each. As a result, it was possible to significantly reduce noise, which was a problem with overwriting in the past, and achieve a comfortable S/N ratio, making it easier to design the device and increasing productivity.

[Brief explanation of the drawing]

Fig. 1 shows a conceptual diagram of track positions showing an embodiment of the present invention, Fig. 2 shows a conventional tunnel erase type magnetic head, and Fig. 3 shows a conceptual diagram showing the process by which old data remains unerased. It is a diagram. 1...Positioning error, 2...Track positioning position, 6...
Inner circumference seek position, 4...Outer circumference seek position.

Claims (1)

[Claims] By means of a servo system with inherent positioning error,
This is an FDD recording method in which a single-gap recording/reproducing head is positioned on a target track and recording is performed in a target sector of the track, and after positioning the recording/reproducing head on the target track, The recording/reproducing head is sought from the positioning position to the inner circumference and outer circumference by a distance corresponding to the positioning error, and after erasing old data in the target sector at each seek position, new data is recorded at the original positioning position. An FD characterized by a recording method that prevents old data from remaining unerased due to positioning errors.
How to record D.