JPH0696511A - Magnetic disk apparatus - Google Patents

Abstract

PURPOSE:To obtain a magnetic disk apparatus wherein, even when a shock nor a vibration is given, data can be written to the center of a track and no error is caused in a readout operation. CONSTITUTION:A shock sensor 5 which detects a shock/a vibration given to a magnetic head 2 is installed. During the write period of data onto a data part, the shock/the vibration given to the magnetic head 2 is detected. When the shock/the vibration which is larger than a certain extent is given during the period, the data is written again.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device mounted on, for example, a portable computer.

[0002]

2. Description of the Related Art Portable computers are often subject to shock and vibration during use. Therefore, the magnetic disk device mounted on the portable computer is required to have shock resistance and vibration resistance. For example, when shock or vibration is applied to the magnetic head when writing data on the magnetic disk,
The magnetic head causes off-track, and data is written off the center of the track. Therefore, a read error occurs when reading data onto the magnetic disk. Therefore, conventionally, the positioning error is monitored based on the servo data written on the magnetic disk, and when an error of a certain value or more occurs, the writing of data on the magnetic disk is temporarily prohibited, and then rewriting is performed. I was going to do it.

However, in the magnetic disk device adopting the servo sector system, since the positioning error can be monitored only during the period when the servo data of each sector is written, a short-term shock or vibration applied to the sector data area period is detected. Can not do it. Therefore, in this case,
The data is written off the center of the track, an error occurs during reading, and it is necessary to perform error processing.
In some cases, an uncorrectable error occurred.

[0004]

As described above, in the conventional magnetic disk drive employing the servo sector method, data is written off the center of the track due to a short-term shock or vibration, and an error occurs during reading. was there.

The present invention has been made in view of the above circumstances, and provides a magnetic disk device in which data can be written in the center of a track even when shock or vibration is applied, and an error does not occur during reading. The purpose is to do.

[0006]

In order to solve such a problem, the present invention provides a method for reading / writing data onto / from a magnetic disk.
A magnetic head for writing and a shock applied to the magnetic head when writing data on the magnetic disk.
An impact / vibration detecting means for detecting the vibration and a control means for controlling to rewrite the data on the magnetic disk when the impact / vibration detecting means detects the impact / vibration more than a predetermined value. To have.

[0007]

In the present invention, the shock / vibration detecting means for detecting the shock / vibration applied to the magnetic head is provided, and the data is rewritten when the shock / vibration detecting means detects a shock / vibration more than a predetermined value. Therefore, data can be written in the center of the track even if shock or vibration is applied,
No error occurs during reading.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a magnetic disk device according to an embodiment of the present invention. This magnetic disk device employs a servo sector system.

In the figure, 1 is a spindle motor for driving the magnetic disk D to rotate, and 2 is a magnetic head for reading / writing data on the front and back sides of the magnetic disk D, respectively. The magnetic head 2 is attached to the tip of the carriage arm 3 and is moved in the radial direction of the magnetic disk D by driving the voice coil motor 4. An impact sensor 5 is attached to the carriage arm 3 to detect an impact / vibration applied to the magnetic head 2. Impact sensor 5
For example, PKS1-4A1 (manufacturer Murata Manufacturing Co., Ltd.) that outputs an electric signal (for example, voltage value) according to external shock / vibration is used. Impact sensor 5
The electrical signal output from is input to the shock signal processing unit 6.

Further, 7 is a disk controller for controlling the operation of data transfer performed with the host, 8 is a read / write circuit for encoding / decoding data, and 9 is a signal read from the magnetic disk D. A head amplifier 10 that amplifies a signal to be written to the magnetic disk D is a CPU that controls the operation of the entire apparatus.

FIG. 2 is a circuit diagram showing the configuration of the shock signal processing section 6. The shock signal processing unit 6 shown in the figure includes a comparator 11, an AND circuit 12, and a flip-flop 13. In the comparator 11, the electric signal S1 output from the shock sensor 5 is compared with a predetermined threshold level L, and when the electric signal S1 is higher than the predetermined threshold level L, the comparator 11
Signal S2 is output. The predetermined threshold level L is, for example, a value corresponding to shock / vibration to the extent that the magnetic head 2 causes off-track. The signal S2 output from the comparator 11 is logically ANDed with the write signal WG output when the data output from the disk controller 7 is written to the magnetic disk D by the AND circuit 12. The signal S3 output from the AND circuit 12 is held by the flip-flop 13. The signal (write fault signal) S4 output from the flip-flop 13 is input to the CPU 10. Since this magnetic disk device adopts the servo sector system, each track of the magnetic disk D used in this device is divided into a plurality of sectors as shown in FIG. As shown in FIG. 4A, a servo data section in which a servo signal is written and a data section in which original data is written are formed. Therefore, the write signal WG is input to the AND circuit 12 only during the period of the data section as shown in FIG. When a shock or vibration is applied to the write signal WG for a certain period or more, a signal S2 is output from the comparator 11 as shown in FIG. As a result, the write fault signal S4 as shown in FIG. 4 (d) is output.

Now, the write operation of the magnetic disk device thus constructed will be described with reference to the flow chart shown in FIG.

When a data write command is received, first the magnetic head 2 is moved to a target track on the magnetic disk D (step 501), and data write is started from this track (step 502). When the data writing is completed (step 503), it is confirmed whether or not the write fault signal S4 is output from the flip-flop 13 (step 504). When the write fault signal S4 is output from the flip-flop 13, the process returns to step 501 and data is rewritten from the beginning. To rewrite the data, the fact may be notified to the host and the data may be retransmitted from the host. Alternatively, although not shown, the data may be retransmitted from the sector buffer provided in the magnetic disk device. .

As described above, in the magnetic disk device of this embodiment, the impact sensor 5 for detecting the impact / vibration applied to the magnetic head 2 is provided, and the impact / impact applied to the magnetic head 2 during the writing of data in the data section. Vibration is detected,
Data is rewritten if shock / vibration is applied to some extent during that period, so data can always be written in the center of the track even if shock or vibration is applied for an extremely short period of time. . Therefore, an error does not occur at the time of reading, and there is no need to perform error processing and no uncorrectable error occurs.

[0015]

As described above, according to the present invention, since the data is rewritten when the shock / vibration detecting means detects a shock / vibration more than a predetermined value, the shock / vibration is not applied. Data can be written in the center of the track, and errors will not occur during reading.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a magnetic disk device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a shock signal processing unit shown in FIG.

FIG. 3 is a diagram for explaining the contents of a magnetic disk adopting the servo sector method.

FIG. 4 is a waveform diagram for explaining the operation of the shock signal processing unit shown in FIG.

FIG. 5 is a flowchart showing a write operation of the magnetic disk device according to the embodiment of the present invention.

[Explanation of symbols]

2 ... Magnetic head, 5 ... Impact sensor, 6 ... Impact signal processing unit, 7 ... Disk controller, 8 ... Read / write circuit, 10 ... CPU.

Claims (1)

[Claims] 1. Read / write of data on a magnetic disk
A magnetic head for writing, an impact / vibration detecting means for detecting an impact / vibration applied to the magnetic head when writing data on the magnetic disk, and an impact / vibration exceeding a predetermined level by the impact / vibration detecting means. And a control means for controlling to rewrite the data on the magnetic disk.