JPH05234283A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To make a decision on the execution of a calibration.seek of the magnetic disk device, which performs a calibration.seek, based on the amount of off-tracks. CONSTITUTION:The device is provided with an interface system and an interface controlling circuit 101, a controlling circuit 102 of the magnetic disk device, an off-track amount measuring circuit 103, a reading circuit 104 and a magnetic disk enclosure 105. The circuit 102 periodically measures the amount of off- tracks regularly employing the circuit 103 and makes whether a calibration.seek be made or not based on the measurement result. The circuit 103 obtains the amount of off-tracks from the reading data of the enclosure 105 and outputs the amount to the circuit 102.

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, and more particularly to a magnetic disk device for performing a calibration seek.

[0002]

2. Description of the Related Art Today's magnetic disk devices have high track densities, so that accurate positioning is required during seek.

Further, since the magnetic disk device is off-track due to a temperature change, for accurate positioning,
This amount of off-track must be taken into consideration.

As one of the methods for obtaining the off-track amount, several servo correction reference cylinders are provided in the magnetic disk device, and the reference data for calculating the off-track amount of each cylinder is written therein. Keep it. The operation of seeking to these cylinders and collecting the reference data is called calibration seek.

Conventionally, the timing for performing this calibration seek is determined at a predetermined time by using a timer.

[0006]

In this conventional method of performing a calibration seek, the calibration seek is performed even if the off-track amount has not actually changed after the previous calibration seek. However, there is a problem in that the processing efficiency for the host device is reduced.

Further, even if the temperature change in the magnetic disk suddenly occurs for some reason, the calibration seek is not performed by the next predetermined time.
There is a problem that accurate positioning cannot be performed.

The object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a magnetic disk device that performs calibration seek based on the off-track amount.

[0009]

According to the apparatus of the present invention, in a magnetic disk apparatus for performing a calibration seek, the off-track amount is regularly measured, and the calibration seek is performed based on the off-track amount. It is configured to include means for determining whether or not.

Further, the apparatus of the present invention has a structure in which a signal read from a gap portion in a data track is input and an off-track amount is obtained from an integrated value of the signal for a certain time.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

The embodiment shown in FIG. 1 is an interface system and interface control circuit 101 for interfacing with a host device, and a control circuit 102 and control for directly controlling the calibration seek of the magnetic disk device, which are directly related to the present invention. An off-track amount measuring circuit 103 for providing an off-track amount required by the circuit 102,
In addition to the reading circuit 104, the magnetic disk enclosure 105 is provided.

The interface system and interface control circuit 101 interprets a command from the host device, sends a command signal to the control circuit 102 based on the command, and sends data from the host device to the control circuit 102. 102
Sends the data from the host to the host device.

The control circuit 102 is a control circuit of the magnetic disk device directly related to the present invention, which performs work and calibration seek based on command signals from the interface system and the interface control circuit 101, and also measures the off-track amount. Input terminal and a timer 1021.

The off-track amount measuring circuit 103 is also a circuit directly related to the present invention, and is the magnetic disk enclosure 1
The off-track amount is measured based on the data read from the head No. 05 and output to the control circuit 102.

The read circuit 104 controls the read / write of the magnetic disk enclosure 105 and modulates / demodulates the data.

FIG. 2 shows an off-track amount measuring circuit 1 of FIG.
It is a block diagram which shows the structure of 03.

FIG. 3 is a diagram showing the main signal waveforms of the off-track amount measuring circuit 103 of FIG. 1 together with the data track configuration contents. The operation of the off-track amount measuring circuit 103 shown in FIG. 2 will be described below with reference to FIG.

Index signal 201 and sector signal 202 provided from the magnetic disk enclosure 105
Is ORed in the OR circuit 1031 and input to the signal sampling timing creation circuit 1032.

The signal sampling timing generation circuit 1032 is
Immediately after the index signal 201 and the sector signal 202, a read clock 205 is read in order to capture the data in the gap portion shown in the format of the data track 203.
, And outputs the integration control signal 204 and the data acquisition control signal 206.

The integrating circuit 1034 filters the gap part signal of the read data 203 read from the head.
After passing through 33, the signal is fetched, integrated while the integration control signal 204 from the signal sampling timing creation circuit 1032 is true, and the integration result is output.

The result storage circuit 1035 has a data acquisition control signal 20 from the signal acquisition timing generation circuit 1032.
When 6 becomes true, the integration result is fetched from the integration circuit 1034 at that timing and continuously output to the control circuit 102 as the off-track amount measurement result.

The control circuit 102 determines whether or not the calibration seek is necessary based on the thus-provided off-track amount measurement result, and performs the calibration
Controls the execution of seeks.

FIG. 4 is a flow chart showing the procedure for determining execution of calibration seek in the embodiment of FIG.

A branch occurs from the main loop of step 301, and the process proceeds to the subsequent steps.

In step 102, the control circuit 102 first determines whether or not there is a work based on a command from the host device, and if not, the process proceeds to step 105.

If there is work based on a command from the host device, the routine proceeds to step 103, where it is determined whether or not the elapsed time from the time when the immediately preceding off-track amount was measured by the timer 1021 has timed out, If it has not timed out, in step 104, work is performed based on a command from the host device. If timed out, step 1
Go to 05.

The off-track amount is measured in step 105, and the process proceeds to step 106. From the result of measuring the off-track amount in step 105, calibration /
Determine if seek required, step 1 if not
Proceed to 07 to return to the main loop. Step 108 if necessary
Then, the procedure proceeds to step 109 to execute calibration seek, and the procedure proceeds to step 109 to return to the main loop.

In this way, the off-track amount is obtained by integrating the signal read from the gap portion in the data track for a certain period of time, and the execution of the calibration seek is decided based on this off-track amount. The off-track amount can be acquired and an efficient calibration seek can be executed without recording the data format for measuring the off-track amount.

[0031]

As described above, according to the present invention, whether or not to perform the calibration seek is determined based on the off-track amount, so that the off-track amount is large and the calibration seek is performed. If you need to do so, make sure to do so, and if the off-track amount is small and you do not need to perform calibration seek, select not to do it. It is possible to significantly reduce the instruction processing efficiency by significantly reducing the limitation of the execution time of the instruction work of the host device due to the calibration seek work time.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an off-track amount measuring circuit 103 in FIG.

FIG. 3 is a diagram showing a main signal waveform of the off-track amount measuring circuit 103 of FIG. 2 and a configuration of a data track together.

FIG. 4 is a flowchart for explaining the operation of calibration seek in the embodiment of FIG.

[Explanation of symbols]

101 interface system and interface control circuit 102 control circuit 103 off-track amount measuring circuit 104 reading circuit 105 magnetic disk enclosure 1031 logical sum circuit 1032 signal sampling timing creating circuit 1033 filtering circuit 1034 integrating circuit 1035 result storage circuit

Claims (2)

[Claims] 1. A magnetic disk device for performing a calibration seek, comprising means for periodically measuring an off-track amount and determining whether or not to perform a calibration seek based on the off-track amount. A magnetic disk device characterized by comprising: 2. The magnetic disk device according to claim 1, wherein a signal read from a gap portion in a data track is input and an off-track amount is obtained from an integrated value of the signal over a constant time.