JPH01317283A - Head positioning control method and disk device using the same - Google Patents

Abstract

PURPOSE:To shorten the overall processing time by varying the positioning process cycle based on the servo information. CONSTITUTION:When a microprocessor 14 performs the positioning and following processes with high accuracy to a desired track of a head 3, a sector pulse N detours a counter circuit 28 and enters directly an input port P2 of the processor 14. Then the head 3 is positioned by the interruption processing every time the servo information Ic prepared are each boundary of sectors passes through the head 3. In case the high positioning accuracy is not required, the processor 14 inputs the pulse N to the port P2 via the circuit 28. Thus the pulse N is inputted to the processor 14 every (n) times (n: >=2). As a result, the redundant positioning process frequency due to the interruptions can be reduced and the overall processing time is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to head positioning control technology, and in particular to a disk device that positions a head relative to a disk based on servo information recorded in advance on a storage medium such as a disk. Concerning techniques that are effective when applied to, etc.

[Conventional technology]

For example, in a magnetic disk device, a method for controlling the positioning operation of a magnetic head based on servo information recorded in advance on a magnetic disk, which is a storage medium, is as follows.
U.S. Patent No. 4,424,543, U.S. Patent No. 4.51
1938 and US Pat. No. 4,669,004 are known.

In other words, servo control information such as the track number to which the sector belongs and the amount of positional deviation in the width direction of the track is displayed at the boundary of each sector, which is formed by dividing each of a plurality of concentric tracks on a magnetic disk in the circumferential direction. Information is recorded, and the servo information is captured and the magnetic head is positioned based on this servo information at a fixed cycle, triggered by the time when the boundary of the sector where the servo information is recorded passes the magnetic head as the magnetic disk rotates. It performs processing.

[Problem to be solved by the invention]

However, when positioning the magnetic head is performed uniformly at a fixed period determined by the rotational speed of the magnetic disk, the number of sectors, etc., as in the conventional technology described above, it is difficult to perform operations such as high-speed seek operations or recording/reproducing information. The period is set based on the case where highly accurate positioning of the magnetic head with respect to the track center is required. As a result, information is not recorded or reproduced on the magnetic disk, and unnecessary positioning processing is performed even when high-precision positioning operation is not necessarily required, resulting in a problem that processes other than positioning processing are delayed. .

For example, a single microprocessor built into the magnetic disk device is used to control the operation of the magnetic disk device itself and control the exchange of information between the upper information processing device and the magnetic disk device. In the system, positioning processing based on servo information as described above is performed by interrupting the microprocessor at regular intervals, but the microprocessor also requires processing such as sending and receiving information with the upper information processing device and analyzing commands. This results in frequent interruptions, which delays the overall processing time and causes an increase in the response time of the magnetic disk device.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a head positioning control technique that can reduce the frequency of wasteful head positioning processing and shorten the time required for the entire processing.

Another object of the present invention is to provide a disk device with good responsiveness.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

That is, a head of a disk device that performs at least one of recording and reproducing information on a disk via the head, and also performs positioning processing of the head with respect to an arbitrary area of the disk based on servo information recorded in advance on the disk. This is a positioning control method in which the period of head positioning processing based on servo information is variable.

[Effect]

According to the above-mentioned means, when high accuracy is required for positioning the head relative to the disk, such as when recording/reproducing information or during high-speed seek operations, it is possible to achieve the desired positioning accuracy at a predetermined period. In addition to performing head positioning processing, in other cases where high positioning accuracy is not necessarily required, the frequency at which redundant positioning processing is performed is reduced by making the period in which positioning processing is performed relatively long. The time required for the entire process can be shortened.

Further, by using the head position determination control method according to the first aspect, the responsiveness of the disk device is improved.

[Embodiment 1] FIG. 1 is a block diagram showing an example of the configuration of main parts of a disk device to which a head positioning control method according to an embodiment of the present invention is applied, and FIG. 2 is an exploded view of the disk device. The perspective view and FIG. 3 are block diagrams showing an example of the overall configuration of the disk device.

First, as shown in FIG. 2, the disk device of this embodiment has a plurality of disc-shaped disks 1 as information storage media, and the plurality of disks 1 are arranged at predetermined intervals in the axial direction of a drive shaft. The spindle motor 2 is supported in parallel.

The plurality of disks 1 are provided on the side portions thereof so as to face the respective planes of the plurality of adjacent disks 1, and the disks 1 are
A plurality of heads 3 for recording and reproducing information on the disk, and a voice coil motor 5 for driving the heads 3 in the radial direction of the disk 1 via a plurality of arms 4 are located. A disk assembly 7 is configured by being fixed to a common housing 6.

A control board 8 is provided on the lower surface of the casing 6 and holds a group of logic elements constituting each block described later.

On the other hand, as shown in FIG. 3, the control board 8 includes:
An interface controller 10 that controls the exchange of information and commands with an external higher-level information processing device (not shown), and the interface controller XO.
A buffer RAM II in which information exchanged via the buffer RAM II is temporarily stored, a DMA controller 12 that controls exchange of information stored in the buffer RAM II with the outside, and a DMA controller 12 between the buffer RAM II and the disk assembly 7. A storage controller 13 that controls the exchange of information and commands is provided, and these operations are configured to be centrally controlled by a microprocessor 14.

The storage controller 13 converts the NR2 signal to 2-5 based on the synchronization signal from the variable frequency oscillator 15, for example.
Encoder/decoder for converting to a coding system 16. Pulse detector 1 that converts analog signals to digital signals
7. AGC (automatic gain control) amplifier 18. The information recorded on the disc 1 is reproduced through the head amplifier 19 and the like, and the information is recorded through the encoder/decoder 16 and the head amplifier 19 on the side of the disc assembly 7. .

In this case, the disk 1 is provided with a plurality of concentric tracks serving as information recording areas, as shown in FIG. 4, for example. Furthermore, an arbitrary track n is divided into a plurality of sectors in the circumferential direction, and at the boundary between an arbitrary sector m of each track and an adjacent sector m+1, there is a space where the number of the track to which the sector belongs is recorded. Code 1a and head 3 from the center position of the track
A servo information IC including a burst pattern 1b indicating the amount of positional deviation is provided.

When the servo information IC provided at the boundary of the sector passes through the head 3, the digital signal of the servo information IC obtained at the output side of the pulse detector 17 is input to the servo demodulation controller 20. In response to the input, a sector pulse N is sent to the microprocessor 14, and a part of the digitized servo information IC is restored to a clay code via a clay code demodulator 21 whose operation is controlled by the servo demodulation controller 20. The data is configured to be input to the microprocessor 14 after being processed.

Also, when the servo information IC passes through the head 3, the AGC
The analog signal of the servo information IC obtained at the output side of the amplifier 18 is input to the position information demodulator 22 controlled by the servo demodulation controller 20, so that the amount of positional deviation from the center of any track of the head 3 can be determined. The burst pattern shown in FIG. 1 is restored as a burst pattern shown in FIG.

Between the microprocessor 14 and the voice coil motor 5 of the disk assembly 7, the information of the disk 1 of the head 3 that is sent out from the microprocessor 14 based on the servo information IC such as the clay code 1a and the burst pattern 1b is provided. A D/A converter 24 that converts command amounts such as displacement scenery and displacement speed in the radial direction into analogs;
A VCM driver 25 and the like that drive the voice coil motor 5 based on an analog signal from the /A converter 24 are interposed.

Similarly, the spindle morph 2 that rotates the disk 1 is configured to be driven by a spindle driver 26 that is controlled by the microprocessor 14.

Also, the microprocessor 14. VCM driver 25.
Operating power is supplied to the spindle driver 26 and the like from a power supply circuit 27.

Here, in the case of this embodiment, the positioning process (seek operation) of the head 3 between a plurality of tracks is performed by the microprocessor 14 based on the servo information IC such as the gray code 1a and the burst pattern 1b, and the Positioning processing (following operation) to the center position of the same trunk is triggered by the passage of the servo information IC provided at the boundary of a plurality of sectors to the head 3, and the servo demodulation controller 20 sends a message to the input port P2 of the microprocessor 14. It is configured to be executed by an interrupt process triggered by a sector pulse N input to the .

In this case, as shown in FIG. 1, the path of the sector pulses N from the servo demodulation controller 20 to the microprocessor 14 includes counting sector pulses N, and repeating the sector pulses N every time the counted value reaches a predetermined value n. A counter circuit 28 (control means) that inputs one sector pulse N to the microprocessor 14, and an output port P1 of the microprocessor 14.
a switch circuit 29 that is opened and closed by a control logic signal 14a output from the counter circuit 28 to control the input of the sector pulse N to the counter circuit 28; and a switch circuit 3 provided on the path of the sector pulse N that bypasses the counter circuit 28.
0 and an impark 31 that inverts the control logic signal 14a applied from the microprocessor 14 to the switch circuit 29.

The switch circuits 29 and 30 are set to operate so that they are connected when the control logic signal 14a is at the "L" level, and are disconnected when the control logic signal 14a is at the "H" level.
Due to the presence of the inverter 31, the connection or disconnection states of the switch circuits 29 and 30 are reversed each time the logic state of the control logic signal 14a changes, thereby generating sector pulses N in the servo demodulation controller 20.
is input to the microprocessor 14 sequentially via the switch circuit 30 side, or is input to the microprocessor 14 after being thinned out once every n times via the counter circuit 28. controlled.

The operation of this embodiment will be explained below.

First, an outline of general information exchange operations between the disk 1 and an upper-level information processing device (not shown) will be explained.

A command to write or read information to or from the disk 1 from a higher-level information processing device (not shown) is analyzed by the microprocessor 14 via the interface controller 10.

In the case of an information write operation, the head 3 is positioned on the target track of the disk 1 by positioning control as described later by the microprocessor 14, and the write data is stored in the buffer RAM 11 under the control of the DMA controller 12. Once stored, the data is transmitted to the storage controller 13, and then written in the 2-7 encoding system by the encoder/decoder 16.
The signal is converted into a signal, transmitted to the head amplifier 19, and recorded via the head 3 in a data area provided in a predetermined sector in a predetermined track of the disk 1 where the head 3 is positioned.

Conversely, in the case of a data read operation, the head 3 is positioned at the target trunk of the disk 1 under the control of the microprocessor 14, and at this time, the data is detected from the data area in the target sector of the target track via the head 3. The read data in the analog state is sent to the head amplifier 19.
．． After being amplified via an AGC amplifier 18 etc., it is converted into a digital signal by a pulse detector 17, and further converted from an NRZ signal into a 2-7 encoding system by an encoder/decoder 16, and then buffered via a storage controller 13. Stored in RAM11, DM
Under the control of the A controller 12 and the interface controller 10, the data is sent to an upper level information processing device (not shown) according to a predetermined procedure.

Here, positioning processing such as following and seeking operations of the head 3 with respect to the disk 1 by the microprocessor 14 in this embodiment is as follows.

First, the servo demodulation controller 20 outputs a sector pulse N to the microprocessor 14, triggered by the passage of the servo information IC provided at the sector boundary to the head 3, and requests execution of positioning processing.

During a following operation in which the head 3 follows the center position of an arbitrary track, the servo demodulation controller 20 suppresses the autonomous gain adjustment function of the AGC amplifier 18 and bursts the burst pattern in the servo information IC obtained for each sector. After the voltage level of 1b is amplified by the AGC amplifier 18, it is input to the position information demodulator 22 as the current positional deviation amount of the head 3 from the center position of the target track. The positional deviation amount is digitized and input to the microprocessor 14.

The microprocessor 14, which has grasped the amount of positional deviation,
The D/A converter 24. Positioning processing is performed to drive the voice coil motor 5 via the VCM driver 25 and the like.

Further, in a seek operation in which the head 3 is moved from an arbitrary track to another arbitrary track, the signal is amplified by the AGC amplifier 18 whose autonomous gain adjustment function is suppressed by the servo demodulation controller 20, and is amplified by the pulse detector 17 in the subsequent stage. The digitized Gray code 1a for each sector is demodulated via the Gray code demodulator 21 into information such as the track number on which the head 3 is currently located, and is input to the microprocessor 14.

The microprocessor 14 recognizes the current position of the head 3 with respect to the disk 1 from the gray code 1a and the amount of positional deviation, and reads the servo information IC at the previous sector boundary in the same or different track than the current one.
The moving speed of the head 3 is calculated based on the difference from the position obtained from the D/A converter 23. VCM driver 25
, the excitation force of the head 3 by the voice coil motor 5 is controlled so that the speed of the head 3 matches the target speed.

Here, in the conventional case, the sector pulse N generated from the servo demodulation controller 20 is transmitted every time the servo information IC provided at the sector boundary passes the head 3, regardless of the content of processing in the microprocessor 14. Generally, an interrupt is generated in the microprocessor 14 as a trigger to cause the microprocessor 14 to perform a series of positioning processes as described above, but in the case of this embodiment, the following operations are performed. .

That is, when the microprocessor 14 needs to position the head 3 with respect to a target track and follow the target track with high precision, such as when actually recording or reproducing data on the disk 1, the microprocessor 14 performs The control logic signal 14a output from the output capacitor P + is set to the "L" level to connect the switch circuit 30 and disconnect the switch circuit 29, so that the sector pulse N bypasses the counter circuit 28. so as to input it directly to the input port P2 of the microprocessor 14,
The servo information IC installed at the boundary of each sector
The microprocessor 14 sequentially performs the positioning process as described above by interrupt processing each time it passes through.

On the other hand, the microprocessor 14 controls the interface controller IQ, the DMA controller 12 . Unlike when controlling the storage controller 13, etc., actual data recording/reproducing operations are not performed on the disk 1, and high positioning accuracy of the head 3 with respect to a predetermined area of the disk 1 is not necessarily required. In this case, the microprocessor 14 sets the control logic signal 14a to “H”.
level so that the sector pulse N is input to the input port P2 via the counter circuit 28, so that the sector pulse N generated in the servo demodulation controller 20 is
The data is input to the microprocessor 14 once every n times.

As a result, in cases where high positioning accuracy is not required, the frequency of redundant positioning processing performed in the microprocessor 14 by interrupts triggered by the input of the sector pulse N is reduced, and the positioning processing performed by the microprocessor 14 is reduced. The overall processing time including processing other than the positioning processing is shortened.

This is shown in FIGS. 6 and 6 for the case of the first embodiment and the conventional case, focusing on the operation of the microprocessor 14 in the process of reading target data from the disk 1 including the seek operation. This is Figure 8.

That is, in the conventional case shown in FIG.
The read preparation process 304 requires positioning with high precision with respect to the disk 1. Seek end processing 3051 Rotation wait 306. Interface processing 301 other than data read processing 307 that does not require much precision. Command analysis processing 302, seek preparation processing 303. Regarding data transfer processing 308 and interface processing 309, high-precision following processing 310 and seek processing 311 are sequentially performed by the microprocessor 14 in relatively short cycles by interrupts triggered by sector pulse N.

On the other hand, in the case of the first embodiment shown in FIG. 6, the interface processing 301 does not necessarily require high precision.
．． Command analysis processing 302. Seek preparation process 303. Data transfer processing 308. During the interface processing 309, the control logic signal 14a is set to the "H" level, and the sector pulses N are thinned out through the counter circuit 28, that is, by lengthening the input period of the sector pulses N to the microprocessor 14, the microprocessor 14, the frequency of redundant high-precision following processing 310 performed in response to input of sector pulse N is reduced.

In addition, lead preparation process 3 requires high precision positioning.
04. When performing the seek end process 3051, rotation wait 306, and data read process 307, the control logic signal 14
a to L" level, all sector pulses N from the servo demodulation controller 20 are input to the microprocessor 14 bypassing the counter circuit 28, and seek processing 311 is performed.
and servo demodulation of high precision follow ink processing 310 =
20- Execute sequentially every time a sector pulse N occurs in the controller 20.

As a result, in the case of the first embodiment shown in FIG. 6, compared to the conventional case shown in FIG. This is reduced by an amount equivalent to six times the time occupied by the microprocessor 14.

In this way, for example, the time required when the microprocessor 14 performs processing other than positioning processing can be reduced by about 1 ms from about 3 ms.

As a result, responsiveness in exchanging information and commands between the disk device and the higher-level information processing device is improved.

In addition, in response to faster operation and increased storage density in disk devices, faster seek operations and higher accuracy of follow ink during recording and playback have been promoted, and as the cycle of positioning processing becomes shorter, The more complicated the interface processing with the higher-level information processing device, the greater the effects of this embodiment.

[Example 2] FIG. 5 is a flowchart showing a second embodiment of the present invention.

In the second embodiment, the sector pulse N generated by the servo demodulation controller 20 each time the area of servo information 1c provided at the boundary of a plurality of sectors passes the head 3.
The microprogram that controls the microprocessor 14 determines whether or not positioning processing is to be performed by interrupt when the input signal is input.

That is, when a sector pulse N is input from the servo demodulation controller 20, the microprocessor 14 executes a position determination process every time the sector pulse N is input based on a flag set in advance according to the content currently being executed. Determine whether or not to do so.

(Step 401) If it is required to perform positioning processing according to the input cycle of sector pulse N, it is further determined whether the required positioning processing is seek processing or follow ink processing. step 402), seek processing (step 404) or following processing (step 4
05).

On the other hand, if it is determined in step 401 that the positioning process according to the input period of the sector pulse N is not required, a
Step 4: Determine whether the value of the counter that is incremented each time the sector pulse N is input has reached a predetermined value.
03) If not reached, increment the counter every time sector pulse N is input (30 g).

If it is determined in step 403 that the value of the counter has reached a predetermined set value, a low-precision following process is performed (step 406), and the counter is reset to zero (step 407), and one operation is performed.

As a result, during processing that does not necessarily require high positioning accuracy of the head 3, by suppressing the execution of positioning processing by interrupt processing triggered by sector pulse N, the entire processing including positioning processing and other processing can be performed. The time required for processing can be shortened.

FIG. 7 shows this.

In the figure, the period determination process 313 executed in response to the input of the sector pulse N is performed at step 401 in the flowchart of FIG. It consists only of the determination processing in step 403 and the counter increment processing in step 408, and the required time is about 10 μS at most, which is extremely short compared to the time required to perform the actual positioning processing.

Therefore, in this embodiment, compared to the case of the prior art shown in FIG. will be shortened only.

As a result, the time required for the microprocessor 14 to perform processing other than positioning processing, for example, about 3 ms, can be reduced by about 1 ms.

As a result, responsiveness in exchanging information and commands between the disk device and the higher-level information processing device is improved.

In addition, in response to faster operation and increased storage density in disk devices, faster seek operations and higher accuracy of following during recording and playback have been promoted, and as the cycle of positioning processing becomes shorter, The more complicated the interface processing with the higher-level information processing device, the greater the effects of this embodiment.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nor.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

That is, the disk is configured to perform at least one of recording and reproducing information to and from the disk via a head, and to perform positioning processing of the head with respect to an arbitrary area of the disk based on servo information reserved and recorded on the disk. This is a head positioning control method for the device, in which the period of the positioning process based on the servo information is made variable, so that high precision head positioning with respect to the disk can be achieved, for example, when recording/reproducing information or during high-speed seek operations. In cases where high positioning accuracy is required, head positioning processing is performed at a predetermined cycle that achieves the required positioning accuracy, and in other cases where high positioning accuracy is not necessarily required, the cycle in which positioning processing is performed is compared. By reducing the frequency with which redundant positioning processing is performed by lengthening the target time, the time required for the entire processing can be shortened.

Further, by using the head positioning control method according to the first aspect, the responsiveness of the disk device is improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the configuration of main parts of a disk device to which a head positioning control system according to a first embodiment of the present invention is applied, FIG. 2 is an exploded perspective view of the disk device, and FIG. 3 is an exploded perspective view of the disk device. FIG. 4 is a block diagram showing an example of the overall configuration of a disk device; FIG. 4 is a conceptual diagram showing an example of an information storage format on a disk; FIG. A flowchart explaining an example, FIG. 6 is Example 1
FIG. 7 is a time chart explaining the effects of the second embodiment. FIG. 8 is a time chart of an example of the prior art. ■...Disc, 1a...Clay cord, lb...
・Burst pattern, 1c... Servo information, 2...
Spindle motor, 3... Hesode, 4... Arm,
5... Voice coil motor, 6... Housing, 7...
Disk assembly, 8... Control board, 10... Interface controller, 11... Buffer RAM,
12... DMA controller, 13... Storage controller, 14... Microprocessor, 14a
... Control logic signal, 15 ... Frequency variable oscillator, 1
6... Encoder/decoder, 17... Pulse detector, 18... AGC amplifier, 19... Head amplifier, 20... Servo demodulation controller, 21...
Gray code demodulator, 22...position information demodulator, 23
... A/D converter, 24... D/A converter, 25... VCM driver, 26... Spindle driver, 27... Power supply circuit, 28... Count circuit (control means), 29 .30... switch circuit, 31.
...Inverter, N...Sector pulse, P, ...
・Output port, P2...Input hold, 301...
Interface processing, 302...Command analysis processing, 303...Shiichi preparation processing, 304...Read preparation processing, 305...Seek end processing, 306...Rotation wait, 307...Data read Processing, 308...
Data transfer processing, 309...interface processing,
310...High precision following processing, 311...
Seek processing, 312...low precision following processing,
313... Cycle judgment processing, 401-408... Processing steps. Agent Patent Attorney Daiwa Tsutsui

Claims (1)

[Claims] 1. Performing at least one of recording and reproducing information on a disk via a head, and positioning the head with respect to an arbitrary area of the disk based on servo information recorded in advance on the disk. 1. A head positioning control method for a disk device, characterized in that the cycle of the positioning process based on the servo information is made variable. 2. The head according to claim 1, wherein the servo information is provided at boundaries of a plurality of sectors formed by circumferentially dividing a plurality of concentric tracks on the disk. Positioning control method. 3. The operation of the disk device including the positioning process is controlled by a built-in microprocessor, and by interrupt processing in the microprocessor triggered by a sector pulse generated every time the sector boundary passes the head. The positioning process is performed, and the input of the sector pulses to the microprocessor is thinned out by a control means controlled by the microprocessor, thereby making the cycle of the positioning process in the microprocessor variable. A head positioning control system according to claim 2. 4. A microprogram built into the microprocessor is provided with a function of determining whether or not execution of the positioning process triggered by input of the sector pulse to the microprocessor is to be inhibited depending on the type of current process. 3. The head positioning control system according to claim 2, wherein the cycle of said positioning process is made variable. 5. A disk device in which head positioning processing with respect to the disk is performed by any one of the head positioning control methods according to claims 1 to 4.