JPS63282907A - Magnetic disk recording device - Google Patents

Abstract

PURPOSE:To prevent the reduction of the residual magnetism of a track by rewriting the data of the prescribed track when the number of reading the specified track achieves a prescribed number. CONSTITUTION:When the reading processing of data is started, a magnetic head 3 is moved on a desired track 2 and the reading processing is executed. Next, whether the read track 2 is a specified track or not is investigated. When the read track of this time is the specified track, access number data N recorded in the prescribed area of the specified track are read. Next, whether these data N achieve a prescribed value A or not is investigated. When the data N achieve the prescribed value A, the data of a specified track are all read and they are once stored in a memory in a computer 15. Next, according to the stored data, the specified tracks are all rewritten. Thus, the reading allowance of a specified track is prevented from reduction and the sudden erasing of the data can be prevented.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to a magnetic disk recording device.

``Prior Art'' In magnetic disks such as floppy disks and hard disks, a specific track is generally used as a directory area in which management and identification information regarding data files is written.

The directory area is often set on the outermost track O. In such a specific track, data is only written when the magnetic disk is initialized and formatted, and there is little chance that the data will be updated during subsequent use. On the other hand, the specific tracks used as these directory areas are tracks from which the magnetic head seeks during the operation of magnetic disk recording tearing, and the data thereof is read very frequently.

If data is read many times on a particular track, the recording condition recorded as residual magnetism on the magnetic disk medium deteriorates, the signal level detected by the magnetic head decreases, and the read margin decreases. However, there was a problem in that it could sometimes lead to data loss.

This problem is particularly important in magnetic disk recording devices used in applications where only read operations are frequently performed, such as those used in game machines. Furthermore, in these devices, not only the tracks used as the directory area but also specific tracks in the data file area are read frequently, which may pose a problem.

"Problems to be Solved by the Invention" The present invention has been made to solve the above-mentioned problems, and it prevents the reading margin of a specific track from decreasing due to repeated reading, and prevents sudden loss of data. The object of the present invention is to provide a magnetic disk recording device that can perform the following steps.

"Means for Solving the Problem" Therefore, the present invention provides a means for storing the number of read ports of a specific track among tracks recorded on a magnetic disk, and a means for storing the number of read ports when the number of read ports reaches a predetermined number. , a means for rewriting all predetermined track data.

"Operation" According to the above configuration, every time the number of reads of a specific track reaches a predetermined number, the data of the predetermined track that is frequently read is rewritten, so that the residual magnetism of the track is prevented from decreasing. Data loss can be avoided.

"Example" Examples of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a block diagram showing a magnetic disk recording device.

A large number of tracks 2 are connected to a magnetic head 3 on a magnetic disk 1.
recorded by. The magnetic head 3 is positioned between the outer circumference and the inner circumference of the magnetic disk 1 by a step motor 4 .

The step motor 4 is of a two-phase excitation type equipped with two sets of excitation coils, and the feed system is configured so that the magnetic head 3 moves onto the adjacent track 2 by rotation of the step motor 4 through four step angles. has been done. Further, the magnetic disk 1 is rotationally driven by a rotary motor 5.

The magnetic disk drive circuit 11 that drives the magnetic head 1 includes:
The main elements are an integrated circuit (for example, Mitsubishi Electric 851017^P) that includes a read circuit section, a write circuit section, a stepping motor drive signal generation circuit section, a modulation/demodulation circuit section, and a logic circuit section in one package. It is configured. Magnetic disk drive circuit 11
directly drives the coil of the magnetic head 3, and drives the stepping motor 4 and the rotary motor 25 through drive circuits 12 and 13 each composed of power transistors. The magnetic disk drive circuit 11 is controlled by a magnetic disk control circuit 14.

The magnetic disk control circuit 14 is an integrated circuit (for example, M5W1793-0 manufactured by Mitsubishi Electric) that houses an interface section, a logic operation circuit section, various registers, etc. in one package.
2P) as the main elements. The magnetic disk control circuit 14 is connected to the computer 15 through various control lines such as a data bus and interrupt requests, and controls the magnetic disk drive circuit 11 based on information from the computer 15.
control.

The magnetic disk control circuit 14 executes control according to a pre-stored program, causes the drive circuit 12 to supply driving power to the rotary motor 5 to rotate the magnetic disk 1 at a constant rotational speed, and receives information from the computer 15. In accordance with the command, the drive circuit 13 supplies a drive pulse to the stepping motor 4 to position the magnetic head 3 at a designated location, and reads the signals stored on the magnetic disk 1 and transmits them to the computer 15. Further, the magnetic head 3 is positioned at a designated location according to a command from the computer 15, and the data transmitted from the computer 15 is written to the designated location on the magnetic disk 1.

The means for storing the number of times a particular track has been read and the means for determining and rewriting the number of times it has been read are realized as processing within the computer 15.

FIG. 2 is a flowchart showing the processing of the first embodiment. In this process, the number of times a particular track 2 has been read is recorded on the magnetic disk 1 and determined.

When the data reading process 100 is started, step 1
At step 01, a normal read process is performed in which the magnetic head 3 is moved onto a desired track 2 and data in a desired sector is read. Next, in step 102, it is checked whether the track 2 from which the data was read this time is a specific track.

A specific track is a track with a particularly high reading frequency.
For example, it is set to the outermost track 0, which is used as a directing area. If the track read this time is not a specific track, the process ends immediately.

If it is a specific track (track O), step 10
Proceed to step 3.

In step 103, access number data N recorded in a predetermined area of that particular track is read.

In a specific track, an area for recording the number of accesses N is pre-formatted. Next, in step 104,
Add 1 to the access number data N, and step 10
It is checked whether the access number data N added in step 5 has reached a predetermined value A. If the predetermined value A has not yet been reached, the process proceeds to step 111, where the added access count data N is written in a predetermined area of the track, and the process 100 ends.

If the access count data N reaches the predetermined value A, the process advances from step 105 to step 106. Stellar 1106 writes 0 to the access number data N of the predetermined area of the track. Next, in step 1.7, all data of a specific track (track 0) is read out along with the format.
It is temporarily stored in the memory within the computer 15. Then, in step 108, that particular track (track 0) is completely rewritten along with formatting according to the stored data.

Note that, depending on the type of program recorded on the magnetic disk 1, there may be a track that is frequently read not only in track O, which is a directory area, but also in track 2, which is a data file area. In such a case, a predetermined track that is read frequently (for example, track 2)
Regarding steps 2 to 25), the same processes as steps 107 and 108 are sequentially executed to rewrite all the data on the predetermined track.

In this way, the number of times a specific track (track 0) is read is recorded in that track, and when the number of reads reaches a predetermined number, rewriting is performed on the predetermined track (for example, track 0 and tracks 22 to 25), and the track is rewritten. Refresh the data.

This embodiment has the advantage that the number of times a particular track on the magnetic disk 1 has been read can be determined with certainty.

However, a special format must be used to record the access number data N on a specific track.

Therefore, the access number data N is not recorded on the magnetic disk 1, but is stored only in the memory in the computer 15, and rewriting of a predetermined track is performed according to the number of readings only while the power is turned on to the magnetic disk recording device. It is also possible to FIG. 3 is a flowchart showing a second embodiment that performs the processing described below. If the track on which the data read process (step 201) was performed is a specific track (track O), the process advances from step 202 to step 204, where the access number data N in the computer 15 is incremented and the access number data is If the predetermined value A is reached, the process proceeds from step 205 to step 206. In step 206, the access number data N is reset to O, and in steps 207 and 208, seven data of predetermined tracks (for example, track 0 and tracks 22 to 25) that are frequently read are rewritten and refreshed.

This embodiment is suitable for application to a magnetic disk recording device installed in business equipment, which is often used for a long period of time with the power turned on.

Furthermore, it is also possible to make it easier to refresh predetermined tracks that are frequently read out uniformly when the power is turned on. FIG. 4 is a flowchart showing a third embodiment for carrying out the above processing. When the power is turned on, the magnetic head 3 is positioned on a specific track (track 0) (step 301), and then all data of that track is read out along with the format and stored temporarily (step 302).
, format, rewrite, and refresh (step 303). This embodiment has a simple configuration;
has the advantage of being applicable to most magnetic disk recording devices.

Furthermore, instead of counting the number of reads of a specific track, it is also possible to directly measure the read margin of a specific track and rewrite the predetermined track according to the measurement result. . FIG. 5 is a flowchart showing a fourth embodiment for carrying out the above processing. This process 400 is executed at an appropriate idle time such as when the power is turned on or after a predetermined time has elapsed. When the process 400 is started, in step 401, the magnetic head 3 is positioned on a specific track (track O) that is frequently read.

Next, in step 402, processing is performed to detect the read margin in that track. To detect the read margin, move the magnetic head to track 0 as shown in Figure 6.
The central position S1 and the positions S2 and S3, which are moved by one step angle on the inner and outer peripheries thereof, are sequentially positioned, and each position Sl,
This is done by checking the number of sectors that the magnetic head 3 was able to read at 82.33. At the center position S1, the entire gap of the magnetic head 3 overlaps with the width of track 0, so a sufficient detection signal level can be obtained (indicated by 31 in the figure).
, position S2. shifted to the inner and outer circumferences. In S3, since the gap of the magnetic head 3 overlaps only half of the track 2 (indicated by 32.33 in the figure), the detection signal level decreases to about 1/2. Therefore, if all sectors can be read at positions S2 and 33 shifted to the inner and outer peripheries, it is determined that the read margin is sufficient. The read margin is detected by determining that the read margin has decreased.

If the read margin is sufficient, the process advances from step 403 to step 407, and the process 400 ends.

On the other hand, if it is determined that the read margin has decreased, the process advances from step 403 to step 404. In steps 404 and 405, all data on a specific track (track O) and a frequently used predetermined track are rewritten, and the process ends. This embodiment has the advantage that rewriting can be performed while grasping the decrease in read margin.

"Effects of the Invention" As described above, the present invention has the above configuration, and rewrites all data on a predetermined track that is frequently read before the recording state of a specific track on a magnetic disk deteriorates. Because of this, it has the excellent effect of preventing a reduction in read margin due to unbalanced use of repeated read operations and preventing sudden loss of data.

[Brief explanation of drawings]

The drawings show embodiments of the present invention; FIG. 1 is a block diagram showing a magnetic disk recording device, FIG. 2 is a flowchart showing the processing of the first embodiment, and FIG. 3 is a flowchart showing the processing of the second embodiment. FIG. 4 is a flowchart showing the processing of the third embodiment, FIG. 5 is a flowchart showing the processing of the fourth embodiment, and FIG. 6 is a schematic diagram explaining the read margin detection processing. 101. magnetic disk, 2. ,,) rack, 31.
. magnetic head, 15. ,,Computer. Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] The present invention includes means for storing the number of times a particular track has been read out of the tracks recorded on the magnetic disk, and means for rewriting all of the data on the predetermined track when the number of times the read has reached a predetermined number. Features of magnetic disk recording device.