CN100458916C - Disk servo information calibration method and its device - Google Patents
Disk servo information calibration method and its device Download PDFInfo
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- CN100458916C CN100458916C CNB2006101253811A CN200610125381A CN100458916C CN 100458916 C CN100458916 C CN 100458916C CN B2006101253811 A CNB2006101253811 A CN B2006101253811A CN 200610125381 A CN200610125381 A CN 200610125381A CN 100458916 C CN100458916 C CN 100458916C
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Abstract
The invention relates to a disk servo information verification method and its equipment. It belongs to the disk servo carve and verification domain, the step of this invention method is: (1) the disk piece installs in the servo carving machine; (2) carries on the servo carve; (3)directly verifies the disk servo signal in servo carving machine; (4) the plate piece servo signal is normal to carry on the step (5), otherwise carry on the step (6); (5) loads the plate piece on the disk driver, carries on finally test; (6) examines whether the plate piece can repair. Can repair transfers the step (2) re-carve the servo signal; otherwise discards the plate piece. This invention equipment includes the servo carve equipment, the filter and the enlargement electric circuit, the partial response biggest likelihood read channel of the piece system chip. This invention has realized the disk servo information verification in the servo carving machine; reduced manual control process and the risk, avoided the processing of duplicating loading and removing disk piece, reduced the carve and verification time of disk servo information.
Description
Technical field
The invention belongs to magnetic disk servo and inscribe and the verification field, be specifically related to a kind of disk servo information calibration method and device thereof.
Background technology
Servo-information is very important for disk, and a fully blank magnetic disk media can't use, need the writing servo signal after, magnetic head could position by servosignal; But in the commercial production of reality, the quality of disc itself and the deficiency of technical existence make and tend to inscribe out inadequately good in the servo carving process or even do not reach the servosignal of requirement, so the verification of servo-information is just seemed very necessary.In the production of disk, disc sheet also need just can further be processed through the test in some steps through behind the servo carving.
The servo code calibration technology of traditional magnetic disk is with the disc of the carving servo-information disk driver interior of packing into, utilizes the read channel of disc driver and control circuit to carry out verification.The flow process of servo carving and verification is as shown in Figure 2: the servo code of a disc sheet is inscribed and verification need be passed through three phases, be loading tray sheet, servo carving, checking signal, three phases all must be finished in clean room, if the underproof situation of verification takes place, then needs to carry out the work of extra dismounting disc.The actual servo verification qualification rate of high-density disk production now is not that very high, the traditional so outer servo code verification of inscription machine can bring following two problems naturally:
1. manually-operated is too much, brings risk for the quality of product.
Load disc and the dismounting disc all needs manually-operated, therefore very easily produce static discharge and damage the circuit elements device.In the present commercial production, though take all multi-methods to reduce the harmfulness of static discharge, but can't avoid fully.Large scale integrated circuit and pring circuit board assembly all will be controlled static discharge, what especially present magnetic disc head was used is the large reluctance magnetic head technology, it requires Electrostatic Control is the highest in the present electronic product, and wherein only electrostatic potential requires to be controlled at below 100 volts or even 50 volts.The static discharge that too much manually-operated brings has very big injury to the circuit board in magnetic disc head and the disc driver, must influence the performance of disk.
2. repetition loading and dismounting disc sheet process have caused the increase of disk production cost.
When servo code verification qualification rate when not being very high, inevitably repetition loading disc and these two processes of dismounting disc have repeatedly caused a large amount of wastes in time, cause the unnecessary waste of material simultaneously.Repetition loading and dismounting disc sheet these two processes can increase disc and rest on time clean room in repeatedly, also can reduce the utilization factor of the servo carving machine of costliness simultaneously, and consequence is to have increased the disk production cost of products.
Summary of the invention
The invention provides a kind of disk servo information calibration method and device thereof, purpose is in verification, improve the utilization factor of servo carving machine, reduce manually-operated and production procedure, thereby reduce disc sheet carries out servo carving and verification under clean room environment time loss, improve the quality of products and reduce cost of products.
A kind of disk servo information calibration method of the present invention comprises the steps:
(1) the sabot sheet is to the servo carving machine;
(2) carry out servo carving;
(3) the direct servosignal of verification disk on the servo carving machine comprises servo carving UC substep and on-chip system chip control substep; The location of servo carving UC substep control head, magnetic head read and write magnetic disk media, the quantized signal that verification is come from the parallel port data line passback of hard disk; On-chip system chip control substep is provided with the every register value in the on-chip system chip, by interrupt handling routine, and the signal amplitude of each hard disk sector after the quantification that generation is used for returning;
(4) servosignal of disc normally then carries out step (5), otherwise carries out step (6);
(5) load disc to disc driver, carry out final test;
(6) can the check disc be repaired, and can repair then changes step (2) and inscribe servosignal again; Otherwise give up disc.
Described disk servo information calibration method, it is characterized in that, described servo carving UC substep is: (1) carries out verification in zone, the disc sheet center of circle, zone line and outer edge area 500～2000 roads of sampling respectively, and head position is to sampling verification magnetic track; (2) the servo carving machine sends check command by the parallel port of hard disk to the on-chip system chip of hard disk; (3) read head of servo carving machine reads servosignal; (4) servosignal that reads is sent to on-chip system chip and carries out analog to digital conversion and quantification treatment, the servosignal that obtains quantizing after filter amplification circuit is handled; (5) give the servo carving machine with the servosignal that quantizes by the parallel port loopback of hard disk, in the servo carving machine, carry out verification; (6) after verification finishes, keep the result of verification with document form.
Described disk servo information calibration method, it is further characterized in that: in the described servo carving UC substep, the checking algorithm that carries out verification in the servo carving machine comprises the steps: that in proper order (1) is provided with abnormality mark ExcFlag and verification number of times Count, is initialized as 0; (2) the array BurstFlag[that comprises 100 status informations is set], initialization value is 0; (3) give BurstFlag[according to being sampled the magnetic track sector auxiliary information] set; (4) judge whether abnormality mark ExcFlag is 1, if not, continue step (5), if ExcFlag is 1, change step (8); (5) the servo carving machine is analyzed the quantized data that returns (BurstFlag[]), and each value of array is 1, continues step (6), otherwise changes step (7); (6) servo carving machine magnetic head is moved to next sampling verification magnetic track, change step (2) then; (7) abnormality mark ExcFlag is put 1, the verification number of times is added 1, and current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[], forward step (2) then to; (8) with current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[]; (9) whether verification number of times Count is not to continue step (10) less than 5, is then to change step (2); (10) calculate BurstFlag[SecNum] in 5 verification mean values of non-1 element number, and record continues step (6).
Described disk servo information calibration method is characterized in that, described on-chip system chip control substep is in proper order: (1) on-chip system chip initialization; (2) wait for the order that transmits from the parallel port data line; (3) judge whether the order that receives is check command, is then down to carry out, continue to wait for otherwise change (2); (4) opening servosignal interrupts; (5) on-chip system chip reads simulating signal and the processing through each hard disk sector after the filter amplification circuit; (6) handle after with orderly being kept in the defined array of the amplitude of every kind in servosignal signal; (7) closing servosignal interrupts; (8) quantized signal after handling by the parallel port loopback is to the servo carving machine.
A kind of disk servo information calibration equipment of the present invention, comprise servo carving equipment, the read head that it is characterized in that servo carving equipment is connected with the partial response maximum likelihood read channel PRML order electric signal of filter amplification circuit, on-chip system chip, and the partial response maximum likelihood read channel PRML output of on-chip system chip is delivered on the servo carving equipment.
Described disk servo information calibration equipment is characterized in that described filter amplification circuit is 7 rank low-pass filtering and amplification Bei Saier circuit.
The present invention to servo carving equipment, has carried out a series of improvement to the servo carving machine with the signal processing applications of disk driver interior:
1. in order to obtain correct check results, the good signal source is essential, designs a cover signal filtering amplifying circuit for this reason.
2. for checking signal is effectively analyzed, filtering must be become digital signal with the analog signal conversion that amplification obtains afterwards.The front filter amplification circuit is handled after the partial response maximum likelihood read channel PRML processing of signal later by the on-chip system chip on the printed circuit-board assembly of disk, just finishes the analog-digital conversion process of signal.Simultaneously, give the servo carving machine with the quantized data loopback that obtains.
3. design the new servo checking algorithm of a cover, finish servo verification.
The servosignal verification has three key links: extract servosignal from servo disc, set up the read channel of magnetic signal, servosignal is quantified as analyzable digital signal.The present invention to servo carving equipment, combines closely servo carving process and signal checking the signal processing applications of disk driver interior, has realized the disk servo information verification in the servo carving machine; The risk that has reduced manually-operated process and may bring has been avoided repeatedly repetition loading and the process of dismantling disc, has reduced the time of disk servo information writing and verification.
Description of drawings
Fig. 1 is a servo-information method of calibration schematic flow sheet of the present invention;
Fig. 2 is existing servo carving and signal checking schematic flow sheet;
Fig. 3 is a servo carving UC substep schematic flow sheet;
Fig. 4 is the schematic flow sheet of checking algorithm;
Fig. 5 is on-chip system chip control substep schematic flow sheet;
Fig. 6 is a servosignal calibration equipment structural representation of the present invention;
Fig. 7 is the circuit diagram of filter amplification circuit.
Embodiment
As shown in Figure 1, method of the present invention is to realize checking procedure in the following manner: behind the servo-information of having write a disk, be not to carry out the verification servosignal as traditional pattern-loading disc in disc driver, the servo-information to disk carries out verification but do not break away under the situation of servo carving machine immediately at disc sheet.If the servo-information of disc normally then disc carrier is carried out final test in disc driver, disc can not repaired then disc directly enters erasable flow process and inscribes the raw material of servosignal as secondary if the servo-information of disc reaches requirement, otherwise enters the flow process of giving up.
The servosignal step of verification disk comprises two parts in the method for the present invention: servo carving UC substep, on-chip system chip control substep.Wherein the major function of servo carving UC substep is the location of control head, magnetic head read and write magnetic disk media, and the verification quantized signal of coming from the parallel port data line passback of hard disk.On-chip system chip control substep then is mainly used to be provided with the every register value in the on-chip system chip, by interrupt handling routine, and the signal amplitude of each hard disk sector after the quantification that generation is used for returning.
Fig. 3 represents servo carving UC substep schematic flow sheet.Nowadays the track density of disk is very high, is that 1.0 inches micro harddisks of 6G are example with the capacity, and track density is about 100K, if adopt the mode of magnetic track verification one by one, will expend time in a large number.Therefore the present invention is a model with the sampling checking algorithm, servo-information inscribe finish after, the zone in the close disc center of circle of disc sheet, the zone line of disc and carry out verification away from 1000 roads of sampling out respectively, the zone in the disc center of circle.When head position arrived certain one, the parallel port of being passed through hard disk by the servo carving machine sent check command to the on-chip system chip of hard disk.In order to obtain servosignal to be detected, then the read head by the servo carving machine reads servosignal.Because the check information that can analyze must be the data that quantize, so thereby the servosignal that reads is sent to on-chip system chip after filter amplification circuit is handled carry out the servosignal that quantification treatment obtains quantizing.Servosignal after will quantizing is again given the servo carving machine by the parallel port loopback of hard disk.The servosignal of the quantification that verification passback is come in the servo carving machine is kept the result of verification simultaneously with document form, after verification finishes, the result of whole checking procedure is sent to management node, and according to the result evaluation grade of verification.
Checking algorithm proposed by the invention belongs to the sampling verification, zone in the close disc center of circle of disc, the zone line of disc and extract 1000 roads respectively out away from three zones, zone in the disc center of circle and carry out verification is looked at the information whether each road can both be read 100 hard disk sectors normally.Because following several abnormal conditions may appear in the problem of external interference factor and disc in the middle of checking procedure:
1: if disc exists the situation of error code or scratch in the middle of the process that writes, cause several hard disk sector signal errors, microprocessor in the hard disk on-chip system chip may can't receive the servo interrupt signal when handling these several hard disk sectors, cause can't entering interruption all the time.
2:, can't enter interruption because extraneous disturbance factor causes certain normal hard disk sector signal can't start the servo interrupt signal in the verification first time.
In view of above several situations, so set up cover checking algorithm mechanism as shown in Figure 4:
1. abnormality mark ExcFlag and verification number of times Count are set, are initialized as 0.
2. because each magnetic track has 100 sectors, therefore the array BurstFlag[that comprises 100 status informations is set], initialization value is 0, if obtain normal certain hard disk sector SecNum, and the servo-information of this sector is correct, then with BurstFlag[SecNum] be set to 1.
3. perfect condition is 100 interruptions of microprocessor startup in the hard disk on-chip system chip, promptly by each sector start information of magnetic track as the down trigger condition, and will be through the BurstFlag[SecNum of the sector correspondence that verification is justified] assignment is 1, final array BurstFlag[SecNum] each is 1.The experiment proved that the probability that this situation exists is approximately 75%.
4. whether abnormality mark ExcFlag is 1, if not, then show abnormal conditions up to the present not occur, and forward algorithm steps 5 to.If ExcFlag is 1, then forward algorithm steps 7 to.
5. the servo carving machine is analyzed the quantized data that returns (BurstFlag[]), if the situation of array element non-1 is arranged, then enters algorithm steps 6.Perhaps each value of array is 1, then forwards algorithm steps 10 to.
6. abnormality mark ExcFlag is put 1, the verification number of times is added 1, and current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[], forward algorithm steps 2 then to.
7. with current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[], enter algorithm steps 8 then.
8. whether verification number of times Count is less than 5, if not then entering algorithm steps 9; If then change algorithm steps 2, continue duplication check.First kind of considering light degree is unusual, or second kind of unusual possibility occurrence, when the situation of array element non-1 takes place, not necessarily just represent disc that problem is arranged or can not solve by repairing or shielding, when therefore unusual situation takes place, the verification number of times of this magnetic track is brought up to 5 times.
9. after adding up 5 verifications, calculate BurstFlag[SecNum] in 5 verification mean values of non-1 element number, and note, enter algorithm steps 10 then.
10. servo carving machine magnetic head is moved to next sampling verification magnetic track, forward algorithm steps 2 then to.
Like this by trizonal 1000 continuous road sample survey, the result to verification correctly assesses according to the standard of quality testing, can determine the fine or not degree of disc; If the machine or the disc of servo carving machine have serious scratch or damage simultaneously, can find in time that also the slip-stick artist just can finely tune servo carving equipment in time like this, and handle accordingly repairing disc.
Fig. 5 represents the flow process of on-chip system chip control substep.At first with the on-chip system chip initialization, make on-chip system chip be configured to the pattern of verification work, the value of reasonably regulating each register makes the verification task of not finishing with not clashing.Wait for that the parallel port data line sends order, judge whether this order is check command, interrupt entering interrupt handling routine, otherwise continue to wait for if then open servosignal.In interrupt handling routine, read through each hard disk after the filter amplification circuit
The simulating signal of sector with orderly being kept in the defined array of the amplitude of every kind in servosignal signal, then being closed servosignal and is interrupted after the processing.Quantized signal after handling by the parallel port loopback at last is to the servo carving machine.
Fig. 6 is a servosignal calibration equipment of the present invention, read a pair of difference servosignal RDX and the RDY of disc from the read head of servo carving equipment, carry out filtering through filter amplification circuit, the people's likelihood read channel analog to digital conversion of local acknowledgement by on-chip system chip again, obtain the magnetic signal after the quantification treatment, deliver on the servo carving equipment by the parallel port data line of hard disk, the servo checking data to passback carries out verification on servo carving equipment again.
Required hardware comprises three parts, servo carving equipment, filter amplification circuit and on-chip system chip in the check system.Servo carving equipment adopts the W-1442 type servo carving equipment of Pemstar company, is mainly used to control a pair of difference servosignal of inscribing magnetic disk media and reading disc in this system.Filter amplification circuit is partly finished the preposition amplification of signal, and elimination high frequency noise signal wherein.On-chip system chip is utilized the partial response maximum likelihood read channel of the on-chip system chip on the existing disk pring circuit board assembly, just can with servosignal complete be quantified as effective digital signal.
Fig. 7 represents the circuit diagram of filter amplification circuit, the fundamental purpose of filter amplification circuit is to filter out the high-frequency signal that mixes among RDX and RDY in the middle of the present design, guarantee that simultaneously the frequency between RDX and the RDY is consistent, so the filter amplification circuit that adopts is Bei Saier 7 rank low-pass filtering amplifying circuit models.Can derive the value of the electronic component among Fig. 7 according to the bilateral model of the monolateral model of the computing formula of Bei Saier and Bei Saier 7 rank low-pass filtering amplifying circuits and Bei Saier 7 rank low-pass filtering amplifying circuits:
C
3＝8.6341pF C
4＝41.0619pF C
5＝68.0785pF C
6＝151.5552pF
L
1＝0.127324uH L
2＝0.127324uH L
3＝0.275338uH
L
4＝0.275338uH L
5＝0.427331uH L
6＝0.427331uH R
1＝R
2＝50
Claims (6)
1. a disk servo information calibration method comprises the steps:
(1) the sabot sheet is to the servo carving machine;
(2) carry out servo carving;
(3) the direct servosignal of verification disk on the servo carving machine comprises servo carving UC substep and on-chip system chip control substep; The location of servo carving UC substep control head, magnetic head read and write magnetic disk media, the quantized signal that verification is come from the parallel port data line passback of hard disk; On-chip system chip control substep is provided with the every register value in the on-chip system chip, by interrupt handling routine, and the signal amplitude of each hard disk sector after the quantification that generation is used for returning;
(4) servosignal of disc normally then carries out step (5), otherwise carries out step (6);
(5) load disc to disc driver, carry out final test;
(6) can the check disc be repaired, and can repair then changes step (2) and inscribe servosignal again; Otherwise give up disc.
2. disk servo information calibration method as claimed in claim 1, it is characterized in that, described servo carving UC substep is: (1) carries out verification in zone, the disc sheet center of circle, zone line and outer edge area 500～2000 roads of sampling respectively, and head position is to sampling verification magnetic track; (2) the servo carving machine sends check command by the parallel port of hard disk to the on-chip system chip of hard disk; (3) read head of servo carving machine reads servosignal; (4) servosignal that reads is sent to on-chip system chip and carries out analog to digital conversion and quantification treatment, the servosignal that obtains quantizing after filter amplification circuit is handled; (5) give the servo carving machine with the servosignal that quantizes by the parallel port loopback of hard disk, in the servo carving machine, carry out verification; (6) after verification finishes, keep the result of verification with document form.
3. disk servo information calibration method as claimed in claim 2, it is characterized in that: in the described servo carving UC substep, the checking algorithm that carries out verification in the servo carving machine comprises the steps: that in proper order (1) is provided with abnormality mark ExcFlag and verification number of times Count, is initialized as 0; (2) the array BurstFlag[that comprises 100 status informations is set], initialization value is 0; (3) give BurstFlag[according to being sampled the magnetic track sector auxiliary information] set; (4) judge whether abnormality mark ExcFlag is 1, if not, continue step (5), if ExcFlag is 1, change step (8); (5) the servo carving machine is analyzed the quantized data that returns (BurstFlag[]), and each value of array is 1, continues step (6), otherwise changes step (7); (6) servo carving machine magnetic head is moved to next sampling verification magnetic track, change step (2) then; (7) abnormality mark ExcFlag is put 1, the verification number of times is added 1, and current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[], forward step (2) then to; (8) with current BurstFlag[] in the array non-1 element number record an overall array ErrorSec[]; (9) whether verification number of times Count is not to continue step (10) less than 5, is then to change step (2); (10) calculate BurstFlag[SecNum] in 5 verification mean values of non-1 element number, and record continues step (6).
4. as claim 1,2 or 3 described disk servo information calibration methods, it is characterized in that described on-chip system chip control substep is in proper order: (1) on-chip system chip initialization; (2) wait for the order that transmits from the parallel port data line; (3) judge whether the order that receives is check command, is then down to carry out, continue to wait for otherwise change (2); (4) opening servosignal interrupts; (5) on-chip system chip reads simulating signal and the processing through each hard disk sector after the filter amplification circuit; (6) handle after with orderly being kept in the defined array of the amplitude of every kind in servosignal signal; (7) closing servosignal interrupts; (8) quantized signal after handling by the parallel port loopback is to the servo carving machine.
5. disk servo information calibration equipment, comprise servo carving equipment, the read head that it is characterized in that servo carving equipment is connected with the partial response maximum likelihood read channel PRML order electric signal of filter amplification circuit, on-chip system chip, and the partial response maximum likelihood read channel PRML output of on-chip system chip is delivered on the servo carving equipment.
6. disk servo information calibration equipment as claimed in claim 5 is characterized in that described filter amplification circuit is 7 rank low-pass filtering and amplification Bei Saier circuit.
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| CNB2006101253811A CN100458916C (en) | 2006-12-08 | 2006-12-08 | Disk servo information calibration method and its device |
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| CNB2006101253811A CN100458916C (en) | 2006-12-08 | 2006-12-08 | Disk servo information calibration method and its device |
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| CN100458916C true CN100458916C (en) | 2009-02-04 |
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| KR20110094299A (en) * | 2008-12-01 | 2011-08-23 | 지라텍스 테크놀로지 리미티드 | Measuring a signal with a spin stand |
| CN114333917B (en) * | 2021-12-30 | 2023-11-03 | 山东云海国创云计算装备产业创新中心有限公司 | RDP erasure algorithm-based data error correction method, device, equipment and medium |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5465182A (en) * | 1992-05-06 | 1995-11-07 | Fujitsu Limited | Recording method of servo information |
| JP2004062942A (en) * | 2002-07-25 | 2004-02-26 | Fujitsu Ltd | Quality evaluation method for servo track writer head |
| US20060126203A1 (en) * | 2004-12-13 | 2006-06-15 | Hitachi Global Storage Technologies Netherlands B.V. | Servo information write method and apparatus |
| CN200979798Y (en) * | 2006-12-08 | 2007-11-21 | 华中科技大学 | A magnetic disk servo information check device |
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2006
- 2006-12-08 CN CNB2006101253811A patent/CN100458916C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5465182A (en) * | 1992-05-06 | 1995-11-07 | Fujitsu Limited | Recording method of servo information |
| JP2004062942A (en) * | 2002-07-25 | 2004-02-26 | Fujitsu Ltd | Quality evaluation method for servo track writer head |
| US20060126203A1 (en) * | 2004-12-13 | 2006-06-15 | Hitachi Global Storage Technologies Netherlands B.V. | Servo information write method and apparatus |
| CN200979798Y (en) * | 2006-12-08 | 2007-11-21 | 华中科技大学 | A magnetic disk servo information check device |
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