JP2674216B2 - Magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial Field B Outline of the Invention C Conventional Technology (Fig. 8) D Problems to be Solved by the Invention (Figs. 9 and 10) E Means for Solving Problems F Action G Implementation Example (G1) Configuration of data format (FIGS. 1 to 4) (G2) Configuration of magnetic disk device (FIGS. 5 to 7) (G3) Other embodiment H Effect of the invention A Industrial 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 which can improve tracking accuracy.

B. Summary of the Invention According to the present invention, in the magnetic disk device, by inserting the servo data in the read / write data portion, it is possible to improve the servo performance while preventing the data capacity from decreasing as much as possible.

C Conventional Technology Conventionally, in magnetic disk devices such as hard disk devices and floppy disk devices, as shown in FIG.
J sectors SECT _j (j = 1, 2 ... J) are provided for each recording track for one revolution formed on the disk DISK, and a preamble PRE and a postamble PST are added to these sector rows SECT _{1 to} SECT _j. In addition, a plurality of recording tracks are concentrically formed.

By the way, in order to read each sector SECT _{1 to} SECT _j ,
It is necessary to accurately track and access the sectors that make up each recording track, and write the servo information SVO of about 50 bytes in advance at the beginning of each sector as the tracking information, and write the data in the write mode, Alternatively, the sector assigned to each recording track can be accessed by controlling the operation of the servo mechanism based on the servo information SVO in the read mode for reading data.

D Problems to be solved by the invention By the way, in this type of conventional magnetic disk device,
As shown in FIG. 9, each sector SECT _j (j = 1, 2, ...
J) has a servo information recording zone SVO _j (j
= 1, 2,... J), followed by an ID information recording zone ID _j and a data information recording zone DATA _j (j =
1, 2 ... J) are sequentially arranged, and the servo information recording zone SVO _j , the ID information recording zone ID _j , and the data information recording zone DATA _j each have the data format shown in FIG. Is designed to be assigned.

In FIG. 10, the servo information recording zone SVO _j has an inter-sector gap data IS that divides adjacent sectors in sequence.
G is assigned and the servo mechanism part of the disk device is controlled by picking up the servo data recorded in a part of the inter-sector gap data ISG.

In the ID information recording zone ID _j , a PLL (phase locked loop) provided in the data processing circuit of the disk device is provided.
p) PLL that generates a reference clock signal by operating the oscillation circuit in synchronization with the data transmission speed of the disk DISK
For synchronization data PLO SYNC, ID data byte synchronization data BYTE SYNC, and the sector number of the sector SECT _j ,
ID data representing information such as head number and sector number
ID, data transmission timing and dummy data PA for adjusting the time delay during data processing in the data processing circuit section
D, and the inter-information gear gap data SPL indicating that the ID information as the data to be transmitted ends and enters the data information,
It is designed to be sequentially assigned in that order.

Further, in the data information recording zone DATA _j , first, the PLL synchronization data PLO SYNC for synchronizing the PLL oscillation circuit of the pickup circuit, the byte synchronization data BYTE SYNC of the read / write data, the read / write data DATA, and the corresponding read The error detection / correction data ECC of the / write data DATA and the dummy data PAD for adjusting the time delay during the data processing in the data processing circuit section are sequentially assigned in that order.

By the way, according to the data format as shown in FIG. 10, for example, the number of sectors J per recording track is set under the conditions of the data transfer rate R _t = 10 [Mbps] and the disk rotation speed N = 60 [rps]. When allocating only J = 32 sectors, the number of bytes B per sector is become.

Therefore, the number of bytes l of the read / write data DATA is 1 =
When 512 [bytes] is selected, in order to read / write the read / write data DATA of the 512 [bytes], in addition to the read / write data DATA, B−l = 651−512 = 319 [bytes] (2 ) Requires 139 [bytes] of redundant bytes,
Therefore, the recording efficiency of read / write data DATA is become.

In this way, based on the data format of FIG. 10, each sector SECT _j (j = 1, 2, ... J) is provided with about 512 [bytes] of data for one sector of read / write data.
It can be seen that when attempting to read and write as DATA, it is necessary to read and write approximately 20 [%] redundant bytes at the same time as the read / write data DATA.

Here, the tracking accuracy and access time of the servo mechanism portion in the disk device can be determined according to the number of servo information recording SVO _j (j = 1, 2, ... J) of each track, and the number of servo information recording zones. As the number of servo errors increases, the number of times the servo error is corrected increases, so that tracking accuracy can be improved.

As a method of improving the performance of the tracking servo in this way, the read / write data DATA is divided by an integer,
For example, a method of dividing into 1/2 and assigning each divided data as read / write data DATA in the data format of FIG. 10 to read / write as one sector of data can be considered.

This method substantially means increasing the number of sectors per recording track, and by doing so, it is considered that the servo performance can be improved by increasing the number of sectors.

However, in this case, there is a problem that the ratio of the read / write data DATA to the data amount for one sector (that is, data recording efficiency) is reduced in the data format of FIG.

In the data format of Fig. 10, read /
Considering the case where the number of bytes l of the write data DATA is selected to be half of the above case, that is, l = 256 [bytes],
Redundant byte count 139 [bytes] described above for equation (2)
Is a disk of read / write data DATA for 1 sector.
Since the management data is necessary for reading and writing to the DISK, even if the read / write data DATA is halved, one sector worth of read / write data DATA is allocated as long as one sector of data format is allocated. Since the management data cannot be reduced, when the read / write data DATA is halved to 1 = 256 [bytes], the ratio of the read / write data DATA to all data is It is still insufficient in that the recording capacity of the disk DISK cannot be effectively utilized as a result, as compared with the case of the equation (3).

The present invention has been made in consideration of the above points, and proposes a magnetic disk device capable of further improving the servo performance while preventing the data recording efficiency of read / write data with respect to the recording capacity of the disk from decreasing as much as possible. Is what you are trying to do.

E Means for Solving the Problems In order to solve the problems, in the present invention, the read / write data parts DATA _k1 , DATA _k2 and the ID data part ID corresponding to the read / write data parts DATA _k1 , DATA _{k2 k}
A read / write data portion DATA _k1 while servo-driving a disk in which unit data sectors configured by the above and first servo data sectors SVO _k1 are sequentially arranged alternately based on the servo data of the servo data sectors. , DATA _k2
In a magnetic disk device configured to write or read read / write data to and from a first servo sector SVO _k1 and SVO _k2 by inserting a second servo sector SVO _k2 at a position where a unit data sector is divided into a plurality of parts. The servo drive is performed based on the servo data of.

F action A new second position is set at the position where the unit data sector is divided into a plurality of parts.
Insert the servo sector SVO _k2 of the
Also, the servo drive can be performed using the servo data of the second servo sectors SVO _k1 and SVO _k2 , and the frequency of detecting the servo data increases. As a result, the servo performance can be further improved as compared with the case where the servo drive is performed only by the servo data of the first servo sector SVO _k1 .

By doing so, by not inserting a new ID data section into the second servo sector SVO _k2 ,
Therefore, the data recording efficiency for the disk DISK can be improved.

G Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

(G1) Structure of Data Format As shown in FIG. 1, the disk DISK has k sectors SECT _k (k = k) for each recording track formed concentrically.
1,2 ... K), and each sector SECT _k (k = 1, 2)
.. (K), as shown in FIG. 2, a first servo information recording zone SVO _k1 , an ID information recording zone ID _k , a first data information recording zone DATA _k1, and a second servo information recording It has a structure in which the zone SVO _k2 and the second data information recording zone DATA _k2 are sequentially arranged in that order.

Here, the first servo information recording zone SVO _k1 and the ID information recording zone ID _k correspond to the servo information recording zone SVO _j and the ID information recording zone ID _j described above with reference to FIG.
As shown in the figure, data having the same structure as the conventional case described above with reference to FIG. 10 is recorded.

That is, in the first servo information recording zone SVO _k1 , the inter-sector gear gap data IS including servo data in part is included.
G is recorded.

In addition, in the ID information recording zone ID _k , the synchronization data for PLL is sequentially
PLO SYNC, byte sync data BYTE SYNC, ID data I
D, dummy data PAD, and information gap data SPL are recorded in that order.

However, in the case of FIG. 3, in the first and second data information recording zones DATA _k1 and DATA _k2 , the read / write data DATA (tenth data) assigned to the data information recording zone DATA _j described above with reference to FIG. (Figure) 1st and 2nd division read / write data which is divided into the first half and the latter half
Second servo information recording zone SVO between DATA1 and DATA2
Data having the same configuration as that provided with _k2 is recorded.

That is, in the first data information recording zone DATA _k1
Sync data for PLL PLO SYNC and byte sync data BYTE
SYNC and the first divided read / write data DATA1 (the number of bytes 1/2 = 256 [bytes] first half data) are recorded.

On the other hand, in the second data information recording zone DATA _k2 , the second divided read / write data DATA2 (byte number l / 2
= 256 [bytes] latter half data), error detection / correction data ECC, and dummy data PAD are recorded.

Also, the first and second data information recording zones DATA _k1 and
Second servo information recording zone SVO provided between DATA _{k2
In k2} , a predetermined number of bytes, for example, 50 bytes of insertion servo data SHV is recorded.

As shown in FIG. 4, the insertion servo data SHV includes dummy data PAD for time delay adjustment, servo data SERVO, and restart synchronization data RESYNC indicating the timing at which the processing of the second divided read / write data DATA _k2 should be restarted. Composed of.

If data is written in or read from the disk DISK by the above data format, two servo information recording zones SVO _k1 and SVO _k2 (k
= 1, 2, ..., K), the number of times servo error information can be supplied to the servo mechanism section in the disk device can be doubled, so that the servo performance can be further improved.

In doing so, the second data information recording zone SVO _k2
As the insertion servo data SVH to be recorded in (Fig. 4), the restart synchronization data RESYNC is inserted after the servo data SERVO, so that when the restart synchronization data RESYNC is picked up, the strong 2-division read / write data DATA is immediately output.
2 (FIG. 3) may be processed for writing or reading,
As a result, the number of redundant bytes of the data amount to be allocated to one sector SECT _k (k = 1, 2 ... K) can be prevented from increasing so much.

When the data format shown in Fig. 9 and Fig. 10 is used, 512 [bytes] is used as the data for one sector.
Minute read / write data DATA and 139 [byte] redundant data, and 139 [byte] redundant data includes 50 [byte] servo information data. On the other hand, in the case of FIGS. 2 to 4, the read / write data DATA is divided into two.
Except that the second servo information data of 50 [bytes] is inserted as redundant data between the first and second divided read / write data DATA _k1 and DATA _k2 of 256 [bytes]. For redundant data, just as in the past
139 including 50 bytes of first servo information data
It is sufficient to have redundant data for [bytes], and thus the amount of servo information data can be dramatically increased without significantly reducing the data recording efficiency of read / write data in the entire disk DISK. .

Incidentally, in the case of FIGS. 2 to 4, the data recording efficiency of the read / write data with respect to the total number of data of one sector is Therefore, it becomes lower than 78% in the case of the formula (3), but it can be prevented from lowering to 64% as in the case of the formula (4).

(G2) Structure of magnetic disk device Magnetic disk device 10 having a structure shown in FIG. 5 as a structure for reading and writing the first and second divided read / write data DATA1 and DATA2 using the data format shown in FIGS.
Can be applied.

In FIG. 5, a magnetic disk device 10 is driven to rotate data to be sent by a read / write data processing circuit 11, a magnetic head 13 and a read / write data circuit 12, and a spindle motor 14. Data is written in or read from the disk 15.

That is, in the write mode, in the sequencer 21 of the read / write data processing circuit 11, the write signal S1 transmitted based on the externally supplied information INF _W to be written is written in the modulator 24 of the modulation / demodulation unit 23 as the write data.
The write amplification circuit 25 of the read / write circuit 12 modulated by S2
It is written on the disk 15 by being supplied to the magnetic head 13 as a write signal S3 via.

On the other hand, in the read mode, the read signal S11 picked up by the magnetic head 13 from the disk 15 is supplied to the peak detection circuit 27 of the read / write data processing circuit 11 via the read amplification circuit 26, and the peak detection is performed. The read data S12 obtained by the differential and zero-cross detection processing in the circuit 27 is AND gate output S through the AND gate circuit 28.
13 is supplied to the data synchronizer 29.

The data synchronizer 29 generates the reference clock signal S14 by pulling the internal PLL oscillation circuit to the synchronous operation state with respect to the PLL synchronization data PLO SYNC included in the AND gate output S13, and modulates and demodulates this. In addition to being supplied to the unit 23, it is supplied to the sequencer 21 as the reference clock signal S15 through the AND gate circuit 30.

Further, the data synchronizer 29 has an AND gate output S1.
When the byte cycle data BYTE SYNC included in 3 is received, the ID data ID and the 1st and 2nd divided read / write data DATA1 and DATA2 that follow are received as a read / write data S16 as a modulation / demodulation unit. It supplies to the demodulator 31 of 23.

It is sent from the sequencer 21 as the leading information INF _R by supplying a read signal S17 obtained by demodulating the read read / write data S16 in the demodulator 31 to the sequence 21.

Thus, the sequencer 21 discards the write information INF _W supplied from the outside to the read / write data processing circuit 11.
Writing on 15, or sent to an external lead information INF _R read from the disk 15 as the output of the read / write data processing circuit 11.

In the read mode described above, when the disk 15 reaches a rotation position where the magnetic head 13 passes the boundary position of each sector, a sector pulse generated at that timing
S19 is supplied to the sequencer 21, which causes the sequencer 2
Sequence processing is executed so that 1 always takes in the corresponding read signal S17 in synchronization with each sector of the disk 15.

In addition to the above configuration, of the read signal S11 picked up from the magnetic head 13 (FIG. 6A), the servo data picked up from the first and second servo information recording zones SVO _k1 and SVO _k2 (first 3) is taken into the servo circuit 41 from the read amplifier circuit 26, and the servo circuit 41 drives the servo based on the servo data.

At the same time, in the servo circuit 41, the magnetic head 13 scans the recording zone in which the servo data SERVO is recorded among the first and second servo information recording zones SVO _k1 and SVO _{k2 based on} the received servo data. During time (6th
As shown in FIG. 6 (A)) and FIG. 6 (B), a miute signal MUTE falling from the logic "H" level to the logic "L" level.
To the control signal generation circuit 42.

When the read / write data processing circuit 11 is in the write mode, this mute signal MUTE is transmitted to other servo data SERVO recorded in the first and second servo information recording zones SVO _k1 and SVO _k2 of the disk 13. It is prevented from being erased by overwriting the data, and in the read mode, the first and second servo information recording zones SVO _k1 and SVO.
_{Prevents the} data synchronizer 29 from malfunctioning (due to input of a servo signal of a signal format different from normal data) due to the servo data SERVO written in _k2 being taken into the read / write data processing circuit 11. As shown in FIG. 6, the control signal generation circuit 42 generates the write inhibit signal WGEN (FIG. 6 (D5)) or the read inhibit signal RGEN based on the mute signal MUTE.
(Fig. 6 (E5)) occurs.

Here, in FIG. 6, the sequencer 21 and the disk 15 are
First data information recording zone at the timing of time points t _{1 to} t _B
An operation when _performing sequence processing of data corresponding to DATA _k1 , the second servo information recording zone SVO _k2, and the second data information recording zone DATA _k2 will be illustrated.

First, in the sequence 21 (FIGS. 6A and 6C) in which the disk 15 is in the first data information recording zone DA in the write mode, the sequencer 21 operates synchronously with the disk 15.
Timing comes to the rotational position of the synchronization signal PLOSYNC of TA _k1 (t ₁₎ write gate signal WG (FIG. 6 (D1)) which rises to the logic "H" level to generate. Along with this, in the sequencer 21, the disk 15 is the first data information recording zone DATA.
_When byte synchronization data BYTE SYNC of _k1 ends t ₃
At the time t ₄ when the first divided read / write data DATA1 ends by counting the number of data pieces of the first divided read / write data DATA1 that has been fetched subsequently after rising to the logic “H” level in A data count signal CNT-1 (FIG. 6 (D2)) falling to the "L" level is generated.

This write gate signal WG and data count signal CNT
-1 is given to the control signal generation circuit 42, and the control signal generation circuit 42 falls of the data count signal CNT-1 (time point t ₄ ).
To fall to the logical "L" level and then the disk
When 15 comes to the rotational position where the restart synchronization data RESYNC of the second servo information recording zone SVO _k2 ends (time t ₅ ), the inhibit signal INH (the sixth signal) that rises to the logic “H” level
Figure (D3)) is generated as an internal signal.

The control signal generation circuit 42 executes a logical product operation of the inhibit signal INH and the write gate signal WG supplied from the sequencer 21, and as shown in FIG. 6 (D4), the clock stop signal CLKENW ( = WG ・ INH) D gate control signal to AND gate circuit 30 through OR gate 50
Give as LCKEN.

At this time, the AND gate circuit 30 is the data synchronizer.
The reference clock signal S14 sent from 29 is prohibited from passing, and thus the reference clock signal S1 is sent to the sequencer 21.
5 is not supplied.

Therefore, at this time, the sequencer 21 is controlled to a state in which the data processing procedure cannot proceed by suspending the sequence processing operation between time points t _{4 and} t ₅ as shown in FIG. 6 (C).

At the same time, the control signal generation circuit 42 executes a logical product operation of the miute signal MUTE (FIG. 6 (B)) and the write gate signal WG (FIG. 6 (D1)) supplied from the servo circuit 41 and the sequencer 21. , As shown in FIG. 6 (D5), the operation result is sent out as a write inhibit signal WGEN (= WG · MUTE), and the write inhibit circuit WGEN causes the write amplifier circuit 25 to be in the write disabled state. The write signal S3 is controlled so that it cannot be supplied to the magnetic head 13.

Here, the disk 13 is the servo data for the miute signal MUTE.
Since it is generated at the timing at the rotation position of the SERVO recording zone, (Figs. 6 (A) and (B)), the write signal S3 cannot be overwritten on the recording zone of the servo motor SERVO. , The servo data SERVO written on the disk 13 is protected.

Thus, in the write mode, the read / write data processing circuit 11 servos the disk 15 at the timing when the second servo information recording zone SVO _k2 passes through the position of the magnetic head 13 in the period from time t _{4 to} time t _{5 in} FIG. At the same time that the data SERVO is protected, the sequencer 21 is controlled so as to stay in the current processing procedure so as not to proceed to the next processing procedure.

When the second servo information recording zone SVO _k2 of the disk 15 finishes passing the position of the magnetic head 13 at time t ₅ in FIG. 6, the control signal generating circuit 42 causes the clock stop signal CL
KENW (FIG. 6 (D4)) is raised to the logic "H" level, and is applied to the AND gate circuit 30 via the OR gate circuit 50 as the gate control signal CLKEN. The operation of supplying the reference clock S15 based on the signal S14 to the sequencer 21 is started.

Therefore, the sequencer 21 is released from the sequence operation halt state at the time point t ₅ to restart the progress to the next processing step, whereby the second write signal S1 is output.
Start sending divided read / write data DATA2.

At this time, the control signal generation circuit 42 becomes the second divided read / write data DATA2 by raising the write inhibit signal WGEN to the write amplification circuit 25 to the logic "H" level (FIG. 6 (D5)). The write data S2 is supplied to the magnetic head 13 as the write signal S3 via the write amplifying circuit 25, whereby the second data information recording zone DATA _k2 of the disk 15 is supplied.
For this, the second divided read / write data DATA2 and the dummy data PAD are written.

Eventually, from the sequencer 21 to the second point at time t ₈ in FIG.
When the transmission of all the data to be recorded in the data information recording zone DATA _k2 of is completed, the sequencer 21 lowers the write gate signal WG (FIG. 6 (D1)) to the logic “L” level to make it logical. The clock stop signal CLKENW (Fig. 6 (D4)) and the write inhibit signal WGEN (Fig. 6)
(D5)) is lowered to the logic "L" level, and the data write operation for the sector SECT _k (k = 1, 2 ... K) is completed.

Thus, in the write mode, the magnetic disk device 10
Are the first and second servo information recording zones SVO _k1 and SVO
It is possible to reliably record the data of the data format shown in FIGS. 2 to 4 to each sector while protecting the servo data previously recorded in _k2 .

In the read mode, the control signal generating circuit 42 corresponds to FIGS. 6 (D1) to (D5) and corresponds to FIGS. 6 (E1) to (E5).
As shown in FIG. 6, when the disk 15 reaches the rotation position of the first data information recording zone DATA _k1 at the time t ₁ in FIG. 6, the sequencer 21 raises the read gate signal from the logic “L” level to the “H” level. G is supplied to the control signal generation circuit 42, and at the time t ₃ , when the byte synchronization data BYTE SYNC falls from the disk 15 and the timing of reading the first divided read / write data DATA 1 comes, the data count signal CNT− By applying 1 (Fig. 6 (E2)) to the control signal generating circuit 42, the control signal generating circuit 42 operates to generate an inhibit signal INH (Fig. 6 (3)).

The control signal generation circuit 42 executes a logical product operation of the inhibit signal INH and the miute signal MUTE (FIG. 6 (B)) supplied from the servo circuit 41 and the read gate signal RG, and FIG. 6 (E4). And (E5), the operation result is sent as a clock stop signal CLKENR (= RG.INH) and a read inhibit signal RGEN (= RG.MUTE), respectively.

Here, the clock inhibit signal CLKENR is at the time points t _{4 to} t _{5 in} FIG.
At the timing at which the inserted servo data SVH, that is, the dummy data PAD, the servo data SERVO, and the restart synchronization data RESYNC (FIG. 4) are read from the disk 15, the logical level falls to the logical “L” level, which is the OR gate circuit 50.
AND gate circuit 3 as gate control signal CLKEN through
By giving 0 as a closing control signal, the reference clock signal S14 of the data synchronizer 29 is controlled so that it cannot be supplied to the sequencer 21 as the reference clock signal S15, and as a result, the sequencer 21 cannot proceed to the next processing procedure. To control.

The sequencer 21 then inserts the servo data SVH
The process waits for the next sequence processing step until the restart synchronization data RESYNC (FIG. 6A) is read. After that, at time t ₅ , the restart synchronization data RESY
When the inhibit signal INH returns to logic "H" due to the fall of NC, the clock stop signal CLKENR rises to logic "H" level and the sequencer 21 restarts the sequence operation. Restarts processing of divided read / write data DATA2.

Further, the read inhibit signal RGEN falls to the logic "L" level (Fig. 6 (E5)) at the timing when the servo data SERVO (Fig. 6 (A)) of the inserted servo data SVH is read from the disk 15. When this is given to the AND gate circuit 28 as a closing control signal, the read data S12 output from the peak detection circuit 27 is transferred to the data synchronizer 29.
Is controlled so that the data cannot be supplied to the device, thereby protecting the data synchronizer 29 from malfunction.

Incidentally, the servo data SERVO has a peculiar signal format in which the servo circuit 41 easily operates in response, and if this is input to the data synchronizer 29 as it is, the data synchronizer 29 may malfunction.

Thus, in the read mode, the servo data SERVO read from the second servo information recording zone SVO _k2 is added to the servo data read from the first servo information recording zone SVO _k1 provided at the head position of each sector. Then, since the servo circuit 41 can perform the tracking servo operation, the tracking accuracy can be further enhanced.

In doing so, the first data information recording zone DATA _k1
After reading the first divided read / write data DATA1 from, the sequence operation of the sequencer 21 is paused while the insertion servo data SVH is being read.
By restarting the sequence operation of the sequencer 21 by the restart synchronization data RESYNC read as the end data of the inserted servo data SVH, the sequencer 21 reads the second divided read / read after the inserted servo data SVH. The write data DATA2 can be processed without excess or deficiency, and the redundant bit can be prevented from extremely increasing in doing so.

The response operation of the magnetic disk device 10 for the inserted servo data SVH in the second servo information recording zone SVO _k2 has been described above, but the servo circuit 41 similarly operates for the servo data in the first servo information recording zone SVO _k1. By sending the miute signal MUTE to the control signal generating circuit 42, it is possible to perform a servo data protect operation in the write mode and a servo data input prohibit operation to the data synchronizer 29 in the read mode.

Second servo information recording zone SVO _k2 (Fig. 6 (A))
The sequencer 21 has a restart data processing circuit 61 having the configuration shown in FIG. 7 as a means for writing or reading the restart synchronization data RESYNC at the end of the.

The restart data processing circuit 61 stores, for example, 1 [byte] of restart synchronization data pattern in the restart synchronization data pattern memory.
In the state in which the original write signal S1X is stored in 61A and the write signal S1X is sent from the first input terminal P1 of the switch circuit 62 as the write signal S1 as the recording data corresponding to each sector in the write mode, the write signal S1 is When it is time to write the restart synchronization data RESYNC in Fig. 6 (A),
The restart synchronization data stored in advance in the restart synchronization data pattern memory 61A is read out in time series and is output from the second input terminal P2 of the switch circuit 62 as the write signal S1 to the modulator 24.
To be sent to the user.

At this time, the modulator 24 writes the write data S2 including the restart synchronization data RESYNC to the disk 15 via the write amplifier circuit 25 and the magnetic head 13 in sequence.

On the other hand, in the read mode, the restart synchronization data RESYNC read from the disk 15 as a part of the read data S11.
The read signal S17 is sent to the restart data processing circuit 61 through the read amplifier circuit 26, the peak detection circuit 27, the AND gate circuit 28, the data synchronizer 29, and the demodulator 31 of the modulation / demodulation unit 23.
Supplied as

In the case of this embodiment, the restart synchronization data RESYNC of the read signal S17 is taken into the shift register 61B for 1 [byte], and the data of each bit is stored in the pitch determination circuit 61C as the restart synchronization data pattern of the restart synchronization data pattern memory 61D. It is determined whether or not each bit matches, and when they match, the sequence operation restart signal REST indicates the match determination circuit 61.
It is sent from C to the sequencer 21.

At this time, the sequencer 21 directly takes in the read signal S17 from the demodulator 31 and immediately restarts the sequence processing of the read signal S17 when the sequence operation start signal REST is generated.

According to the configuration of FIG. 7, the restart synchronization data RESYNC of the second data information recording zone SVO _k2 can be surely read and written to each sector of the disk 15.

According to the above configuration, the first servo information recording zone SVO _k1 is provided at the head position of each sector, and read / write data divided into two, that is, the first and second divided read / write data DATA1 and DATA2. First and second data information recording zones DATA _k1 and DATA for respectively recording
_A second servo information recording zone SVO _k2 is provided between _k2 , and the servo circuit 41 is servo-controlled by using the servo data of these two servo information recording zones SVO _k1 and SVO _k2. As compared with the case where SVO _k2 is not provided, it is possible to obtain the magnetic disk device 10 having significantly better servo performance.

In doing so, the second servo information recording zone SVO _k2
While the insertion servo data SVH is read from, the sequence operation of the sequencer 21 is paused and the completion of the insertion servo data SVH is restarted. Synchronization data RESYN
By reading out C and restarting the sequence operation of the sequencer 21, the amount of redundant data to be newly added can be reduced to the necessary minimum, and thus the read / write data It is possible to easily obtain the magnetic disk device 10 having good data recording efficiency.

(G3) Other Embodiments (1) In the above-mentioned embodiment, one servo information recording zone, that is, the second servo information recording zone SVO _k2 other than the servo information recording zone SVO _k1 provided at the head position of each sector. However, the number of servo information recording zones newly provided is not limited to one,
Even if two or more are selected as needed, the same effect as the above case can be obtained.

(2) In the embodiment shown in FIG. 5, the restart data processing circuit 61 is provided between the sequencer 21 and the modulator unit 23, but instead of this, it is provided on the read / write circuit 12 side of the modulation / demodulation unit 23. It may be provided.

By the way, in this case, if the deviation of the operation timings of the modulation / demodulation unit 23 and the sequencer 21 is set accurately, the same effect as the above case can be obtained.

(3) In the above embodiment, the insertion servo data SV
Servo data SERVO as H followed by restart synchronization data RE
By inserting SYNC, the word division of the second divided read / write data DATA2, which is serial data to be transmitted subsequently, is achieved. However, for example, the second servo information recording zone SVO _k2 becomes longer, Data synchronizer 2 for processing divided read / write data DATA2
If it is necessary to resynchronize the PLL circuit of 9, the PLL synchronization data PLO SYNC may be newly added before the restart synchronization data RESYNC.

H Effect of the Invention As described above, according to the present invention, by inserting the servo information recording zone in the read / write data portion, the servo information is written on the disk while suppressing the expansion of the redundant data number as much as possible. Therefore, a magnetic disk device capable of improving tracking information and access time can be easily realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showing a disk used in an embodiment of a magnetic disk device according to the present invention, FIG. 2 is a schematic diagram showing the structure of its recording zone, and FIG. 2 is a schematic diagram showing the data format in the recording zone of FIG. 2, FIG. 4 is a schematic diagram showing the structure of the insertion servo data, and FIG. 5 is a block diagram showing an embodiment of the magnetic disk device according to the present invention. FIG. 6 is a signal waveform diagram for explaining the writing / reading operation of the servo data, FIG. 7 is a block diagram showing a restart data processing circuit, FIG. 8 is a plan view showing a conventional disk, and FIG. FIG. 10 is a schematic diagram showing the structure of a recording zone, and FIG. 10 is a schematic diagram showing a conventional data format. 10 ... magnetic disk device, 11 ... read / write data processing circuit, 12 ... read / write circuit, 13 ... magnetic head, 14 ... spindle motor, 15 ... disk, 41 ...
Servo circuit, 42 ... Control signal generation circuit, 61 ... Restart data processing circuit, 62 ... Switch circuit.

Claims (1)

(57) [Claims] 1. A read / write data section and the read / write
A disk in which a unit data sector composed of an ID data part corresponding to the write data part and first servo data sectors are sequentially arranged alternately is driven based on the servo data of the servo data sector. In a magnetic disk device configured to write or read read / write data in the read / write data section while performing the above, a second servo sector is inserted at a position where the unit data sector is divided into a plurality of parts, A magnetic disk device, characterized in that the servo is driven based on servo data of a second servo sector.