KR20010053204A - Variable disc drive cylinder recording system - Google Patents

Abstract

A method for dynamically mapping known downstream execution heads for disk drives to reduce the likelihood of expensive manufacturing rework on the entire drive. Using heads in disk drives that perform better than average, the method can write many bits per density on a particular head. This is particularly appropriate when zone recording 300 is performed and is known to limit the recording density for cylinder groups 310, 330, 350 and 370. Frequency adjustment of the head (lower write frequency) within the cylinder allows for a variable logic block addressing configuration corresponding to the user's desired data access layout. Several tracks can be accessed, while others can be reserved for system data. The method described works particularly well in a headerless architecture. The performance of subordinate or "bad" heads can be improved.

Description

Variable disk drive cylinder recording system {VARIABLE DISC DRIVE CYLINDER RECORDING SYSTEM}

One of the main components of any computer system is a place for storing data. Computer systems have many different places where data can be stored. One common place for storing large amounts of data in computer systems is on disk drives. The most basic components of a disk drive are a rotating disk, an actuator for moving the transducer to various positions on the disk, and an electrical circuit used to write data to and read data from the disk. The disc drive also includes circuitry for encoding data so that it can be retrieved and written to the disc surface. The microprocessor controls most of the disk drive's operation as well as taking data from the requesting computer to pass the data back to the requesting computer and to store it on the disk.

The transducer is typically housed in the slider. The slider is a small ceramic block passed over the disc in transducing relationship with the disc. Small ceramic blocks, referred to as sliders, are generally aerodynamically designed to fly over the disc. Most sliders have an air bearing surface ("ABS") that includes a rail and a cavity between the rails. As the disk rotates, air is dragged between the rails and the disk surface causing the pressure, causing the head to be pushed away from the disk. At the same time, air rushing through the depressions in the air bearing face forms a negative pressure region. Negative pressure or suction neutralizes the pressure formed in the rails. The slider is attached to a load spring that creates a force on the slider that is directed towards the disk surface. Various forces are in equilibrium so the sliders fly over the surface of the disc at a specific flying height. Flying height is the gap between the disk surface and the transducing head or the thickness of the air lubrication film. This membrane eliminates friction and wear that occurs when the transducing head and disk are in mechanical contact during disk rotation. In some disc drives, the slider passes through a lubrication layer rather than flying over the surface of the disc.

Information representing the data is stored on the surface of the memory disk. The disc drive system reads and writes information on tracks of a memory disc. Transducers, which are in the form of read / write heads located on both sides of the memory disk and attached to the slider, read and write information on the memory disk when the transducer is correctly positioned over one of the designated tracks on the surface of the memory disk. The transducer is moved to the target track. Once the memory disk is rotated and the read / write head is correctly positioned on the target track, the read / write head can store data on the track by writing information representing the data on the memory disk. Similarly, reading data on the memory disk is accomplished by placing the read / write head over the target track and reading the stored material on the memory disk. To write on and read from a different track, the read / write head is moved radially across the track to the selected target track. Data is divided or grouped together on a track. In some disc drives, the track is a plurality of concentric circular tracks. In other disk drives, the continuous helix is one track on one side of the disk drive. Servo feedback information is used to accurately position the transducer. The actuator assembly is moved to the required position and maintained very accurately during read or write operations using servo information.

When the head actuators hold all the heads corresponding to all the disks together in the same proximal radial position, a vertical stack of tracks is formed, resembling a cylinder. That is, a "cylinder" is a combination of all tracks at a given radial position or at a predetermined head actuator position. In addition, as used herein, the term "zone" refers to a group of one or more cylinders. Zones appear on a single disc surface as groups or bands of recording tracks. In the past, a disc drive had a single "write frequency" defined for all the heads in a zone as the frequency of the entry of data or the writing of data on the disc rotating at fixed angular speeds. Each surface of the disc in the disc drive has an associated read / write or transducer. The transducer is an E-block or comb, a series of arms positioned so that a set of transducers can be moved in unison. During read and write operations, each head is turned on and off separately from the others. The disc surface has zones with different values of the recording density measured in bits per inch. As the disc rotates at a constant speed, different recording frequencies are associated with each zone. In the outer radiation zone, the recording frequency is higher. The data density is higher in the outer radiation zone. In general, the disc drive industry characterizes this reconstruction as "zone-bit write" because of the associated integrity of zones with varying write density values.

Recent attempts to improve read / write heads (here referred to as “heads” or “heads”) yields have resulted in software and hardware zone structures that allow the write frequency to vary uniformly within the zone. That is, the recording frequency of all the heads in the zone is changed to cover any bad performing heads. By lowering the recording frequency of all the heads in the zone, the performance of the "bad" heads can be improved. The result is a loss of the recording frequency of all the heads in the zone. The data capacity is reduced when the recording frequency is lowered. The degree to which the recording frequency is lowered depends on the number of heads in the drive and the amount of margin that a good head has. Some attempts to improve head yield require a constant recording frequency for all heads in the cylinder.

What is needed is a disk drive that can achieve good error rates in order to overcome poor yield problems and increase the performance of all "bad" heads.

The present invention relates to a mass storage device. In particular, the present invention relates to a system for varying the recording frequency per head in the cylinder of a disc drive.

1 is an enlarged view of a disk drive having multiple disk stack and lamp assemblies for loading the transducer to the surface of the disk and unloading the transducer from the disk surface.

2 is a block diagram of a recording channel.

Figure 3 shows the surface of a disk divided into zones.

4 shows a grid layout of a disk drive.

5 is a block diagram of an initial zone reconstructed into subzones.

Fig. 6 is a graphic diagram of bit density formatted in a sub zone.

7 illustrates sequential read / write access.

FIG. 8 shows serpentine type read / write access. FIG.

9 is a flowchart of a method for improving the error rate of a disk drive.

10 is a schematic diagram of a computer system.

The present invention is a method of dynamically mapping known defect heads for disk drives in order to reduce the possibility of expensive manufacturing rework on the entire drive. With heads in drives that perform better than average, the method allows writing high frequency or more bits per inch on a particular head. This is particularly accurate when zone recording is done and is known to limit the recording density for a group of cylinders.

In one embodiment, a method of improving reading and writing information to a disc of a disc drive is to read and write information at a first frequency when in a first zone with a first head, within the same first zone. Accessing the second storage surface includes reading and writing information at the second frequency. Part of the method involves determining that at least one read / write transducer causes less error when operating at a frequency other than the initially assigned frequency.

The method is used on disk drives. The disk drive includes a rotating disk assembly having a first disk surface and a second disk surface. The first read / write transducer operates in transducing relationship with the first disk surface at a first frequency of the first disk zone. The second read / write transducer operates in a transducing relationship with the first disk surface at a frequency different from the first frequency when operating in the first disk zone. In another embodiment, the magnetic disk storage system includes a magnetic disk having two recording surfaces. A read / write transducer is located near each of the recording surfaces of the magnetic disk to read and write information for each of the recording surfaces. The memory is coupled within the disk storage system and coupled to the read / write transducer. The memory contains the offset value of the servo position. The controller is coupled within the disk storage system and coupled to the read / write transducer and the memory. The controller positions the read / write transducer in the disk storage system via the target address as a result of the input based on the number of frequency adjusted heads.

In yet another embodiment, a system for reusing a lower performing read / write head includes a number of write zones for storing data. The change in frequency among the write zones reduces the overall error rate caused by the read / write head. The zone table is used to determine the number of heads served by the zone and the target zone.

Advantageously, the described method works particularly well in a headerless architecture environment. The performance of the lower execution head can be improved. Moreover, a better error rate is achieved and the yield problem is overcome. The present invention results in an increased list price of "arithmetic logic unit (ALU) resources", ie, "calculation resources" without changing the engine performing the calculation. In one aspect of the invention, a "computation resource" includes programmable logic, a computer, an ALU, a controller, or similar other devices capable of calculating head specific and zone to use the lowered recording frequency as derived from the error rate. In addition, it is unlikely that the drive will be discarded or reworked as a result of the lower performance head.

The invention described in this application is useful for all mechanical configurations of disc drives with either rotational or linear motion. In addition, the present invention is useful in all types of disk drives including hard disk drives, zip drives, floppy disks, and other types of drives where it is desirable to unload the transducer from the surface and park the transducer. 1 is an enlarged view of one type of disk drive 100 having a rotary actuator. The disk drive 100 includes a housing or base 112 and a cover 114. Base 112 and cover 114 form a disk seal. An actuator assembly 120 is rotatably attached to the base 112 on the actuator shaft 118. Actuator assembly 120 includes a comb structure 122 having a plurality of arms 123. An arm 123 on the comb 122 is attached with a load beam or load spring 124. The load beam or load spring is referred to as suspension. At the end of each rod spring 124 is attached a slider 126 that carries the magnetic transducer 150. The slider 126 along with the transducer 150 forms what is called a head several times. Many sliders have one transducer 150. The present invention is equally applicable to a slider having one or more transducers, such as referred to as an MR or magnetoresistive head where one transducer 150 is generally used for reading and the other used for writing. On the end of the actuator arm assembly 120 opposite the load spring 124 and the slider 126 is a voice coil 128.

The first magnet 130 and the second magnet 130 ′ are attached to the base 112. As shown in FIG. 1, the second magnet 130 ′ is associated with the cover 114. The first and second magnets 130, 130 ′ and the voice coil 128 are the main components of the voice coil motor that apply a force to the actuator assembly 120 to rotate around the actuator shaft 118. The base 112 is equipped with a spindle motor. The spindle motor includes a rotation called spindle hub 133. In this particular disk drive, the spindle motor is in the hub. In FIG. 1, a number of disks 134 are attached to the spindle hub 133. In other disk drives, a single disk or a different number of disks can be attached to the hub. The present invention disclosed herein is equally applicable to a disc drive having a single disc and a disc drive having a plurality of discs. The invention disclosed herein is equally applicable to a disk drive with a spindle motor under the hub in hub 133.

2 shows a block diagram of a partial response maximum likelihood (PRML) write channel available in disk drive 100. The information to be recorded is to provide a modulated coded output with a predefined runlength limit, such as zeros of the maximum run length and maximum and minimum number of consecutive zeros in odd and even recorded sequences in the entire recorded sequence. Applied to encoder 1001. Precoder 1002 follows encoder 1000 initiated by a 1 / (1-D ² ) operation, where D is a unit delay operator. The PRML precompensation circuit 1004 provides a modulated binary pulse signal applied to the recording circuit 1006 which provides a modulated write current for writing to the disk surface. The analog readout signal is obtained at the head and disk block 1008 initiated by a (1-D ² ) operation. The read signal is applied to a variable gain amplifier (VGA) 1009 and the amplified read signal is applied to a low pass filter 1010 that may or may not provide a Class IV response. The filtered read signal is converted to digital form by an analog-to-digital converter (ADC) 1012 providing 64 capable 6 bit sampled values. The gain and timing control circuit is generally designated by the reference character 1014. Typically, 6-bit samples of ADC 1012 are applied to a digital filter 1016, such as a 10 tap finite impulse response (FIR) digital filter. The filtered signal from the digital filter 1016 is applied to the Viterbi decoder 1018 coupled to the decoder 1020 again to complete the maximum likelihood (ML) detection process for data reading.

Gain and timing control functions include a capture mode of operation and a tracking mode of operation. During the acquisition mode, the gain and timing control circuits 1022 and 1026 are called sync fields that set the VGA amplification to a predetermined voltage level and set the ADC sampling phase to achieve a lock-on suitable for the sync field. The boolean is locked on a given data pattern. After the loop is concentrated during the tracking mode, the gain and timing control circuits 1022, 1026 track customer data to ensure that the signal is locked.

The gain and timing control circuit includes an acquisition gain and timing controller 1022 having a digital signal supplied by the ADC 1012 at line 1013. During the acquisition mode of operation, the acquisition gain and timing control 1022 generates a digital gain control signal on line 1024 to correct the gain of the VGA 1009 and corrects the timing applied to the voltage controlled oscillator (VCO). To generate a digital timing control signal on line 1022. The digital signal on line 1017 is supplied by digital filter 1016 to tracking gain and timing control 1026. Tracking gain and timing controller 1026 generates a digital gain control signal on line 1027A to adjust the gain of VGA 1009 and is applied to voltage controlled oscillator (VCO) 1024 during the tracking mode of operation. A digital timing control signal 1025 is generated to correct the timing. The disk drive 100 includes various electronics. Part of the electronics is the recording channel 1000.

Referring to Figure 3, disk 134 is shown to have zones 0, 1, 2. Each zone 0, 1, 2 and N includes a plurality of tracks. Corresponding tracks on different discs can be said to be similar to cylinders. Cylinders are groups of tracks at equal radial intervals. Zones 0, 1, 2 and N can be said to be formed of a plurality of cylinders when a plurality of recording surfaces are discussed.

The present invention operates on a disk drive such as the disk drive 100 shown in FIG. The invention utilizes a head that performs poorly in a cylinder rather than discarding and reworking during the manufacturing and testing process. Testing is performed to identify heads based on common quality criteria for specific drives and specific manufacturers. According to one aspect of the invention, lowering the recording frequency improves the data quality of the " frequency regulated head " (often " less-than-nomial head ") and provides better error rates to improve production. Bring. In situations where a frequency-controlled head is used at a lower recording frequency, the head is often referred to as an "optimized head" because the head is operated at a recording frequency optimized for the recording characteristics of a particular head. Thus, a nominal, unregulated or unoptimized head is a head that meets the desired data quality details of a particular drive and a particular manufacturer without changing the nominal recording frequency. Lowering the recording frequency is referred to as "optimizing" the recording frequency (optimizing the head includes causing the recording frequency to vary from head to head within the zone structure). Moreover, frequency regulation can reduce the need for remanufacturing of heads in disk drives. In addition, the masking or translation process via software assists the processor in locating the target physical address on the disk drive with a writing frequency that varies from head to head in the cylinder.

In some embodiments, a frequency adjusted head (ie, a head operated at a frequency lower than the nominal frequency in one or more zones) will write less data on the corresponding disk surface compared to the nominal amount of data for the surface. In this embodiment, one or more other heads (ie, nominal heads) are operated at high frequencies to compensate for lower amounts of data on the surface of the frequency adjusted head, recording more than the nominal amount of data and This will maintain the total amount of data on the disk drive at the desired level. For example, if each disk surface is designed to store one gigabyte of data in a disk drive with five platters and therefore ten disk surfaces, the entire disk drive will provide 10 gigabytes of data storage. It is proven to have the characteristic that one head operates at a predetermined error rate, for example, only when using a recording frequency of 99% of the nominal recording frequency (which results in less than one gigabyte of data on that surface) in one or more zones. If so, the other nine nominal heads would operate at about 100.2% of the nominal write frequency (which results in more than one gigabyte of data on its surface) in the same zone. Therefore, in this embodiment, the overall improved disk drive error rate lowers the recording frequency and slightly lowers the amount of denter for the transducer and any (but not all) of the corresponding disk surface, while the transducer and For others on the corresponding disk surface, this is achieved by increasing the amount of data and the recording frequency. At the same time, the total amount of data stored (or storeable) on such a disk drive can be maintained.

In one embodiment, the method is optimized for reading large amounts of data sequentially. In another embodiment, the method is optimized for a read / write function having a serpentine-like structure due to the frequency controlled head subzone intermixed with the unfrequency controlled subzone. The present invention also reconstructs the current zone structure to accommodate head frequency variations within the cylinder.

One embodiment divides the n initial zones into at least n + 1 subzones. Each subzone serves a variable number of cylinders with a fixed number of heads. A fixed number of heads can change from one subzone to another and remain fixed within the subzone. As a result, the number of heads is maintained as a zone specific parameter. One embodiment of the present invention is well suited for operation in a headerless architecture environment. This environment exists when the data address header or tag no longer resides on the disk itself. Instead, the header is in volatile random access memory, " RAM, " or memory of the controller, associated with circuit 160 shown in FIG.

4 shows a grid layout of the disk drive 100, with the heads logically addressed under a logical block address ("LBA") configuration. The block diagram 200 of FIG. 2 shows several heads 210 accessing several tracks 220. For example, cylinder 0 includes all tracks below head 210 (e.g., head 0, head 1, head 2, head 3, head 4), the head being the first track of several tracks. Vertically along each head corresponding to one cylinder face. Each disc 134 has two recording surfaces. Head 0 is associated with the top surface of the first disk 134 of the disk drive 100 and head 1 is associated with the bottom surface of the disk 134. The head 2 is associated with the upper surface of the second disk and the head 3 is associated with the lower surface of the second disk. The head 4 will be associated with one side of the third disk. Although the present invention describes a disk drive 100 having a plurality of disks, it may be applied to a disk drive using a single disk 134.

The cylinder 1 is the next vertical line of the track between several discs and is similar for cylinder 2 to cylinder n, which is the maximum number of cylinders usable universally. The red arrows 240, 242 and 244 indicate that the information under the various heads 210 is read for the entire cylinder during the read operation. In other words, in the cylinder 0, the information under the head 0 is first read, followed by the information under the head 1 and the information under the heads 2, 3 and 4. Dotted lines, such as dashed line 241, represent the next track and cylinder 1 and head switching from head 4 to head 0. The red arrow 242 represents the head switch after reading the information under the head of the cylinder 1. The red arrow 244 represents reading the entire track including the data or information of the cylinder 2. Dotted line 243 represents the switching between cylinders 1 and 2. One feature of the present invention is to determine if one or more heads (0, 1, 2, 3 or 4) perform poorly than the remaining heads. If the head is an insufficient performer, it is known that the performance is significantly improved by reducing the frequency of the read channel for the insufficiently executed head. Improvements can be seen by reducing errors associated with insufficiently executed heads. The read channel or data channel frequency is reduced for heads that are insufficiently executed in the zone. Thus, within a single zone the read channel operates at least two different frequencies, one frequency associated with the good head and the other frequency associated with the insufficiently executed head. The read frequency associated with a good head may be increased to maintain the information capacity of the zone equal to the capacity of the zone before frequency adjustment. The LBA increases horizontally from left to right, from cylinder 0 in the reserve zone 280 to the last cylinder. The reserve zone 280 is typically at the inner diameter of the disk 134. In the spare zone 280, system data exclusively resides in some named portion of the drive. Similarly, the heads 210 are numbered sequentially and vertically on the left side of the diagram in the range 0-4. A track is an accessible user track or extra track that is scattered throughout the drive. The spare track is a spare track that can be arranged for data when the standard user track includes a bet sector.

If the heads do not collide with the spare tracks, each head reads and writes along the corresponding tracks in the entire cylinder to access the data. Since only one head is available at any given moment, the head reads information at different times from the tracks under head 0, head 1, head 2, head 3 and head 4 . Thus, with respect to the cylinder 0, the heads 0 to 4 are not obstructed and all data in the cylinder starting at the head 0 and ending with the head 4 can be accessed. Thereafter, the actuator moves to the first track 220 of the cylinder 1, once again starting at the head 0 and ending with the head 4; Each head accesses the corresponding data on the track without any interruption. However, in the cylinder 2 the heads 3 and 4 collide with extra tracks which hinder data transfer.

Cylinders 0, 1 and 2 are arranged together to form a primitive zone 0, also referred to as zone 230. Similarly cylinders 3, 4, and 5 constitute a primitive zone 1, also referred to as zone 240. System data, including information about the quality of the transducer user head and about the formatting of the track, is located in several zones 280 consisting of several inaccessible cylinders arranged adjacently. In the raw zone shown in FIG. 2, the frequency of the read channel is the same for all heads in the raw zone. In other words, all heads 210 are well determined so that nothing has to be frequency tuned. Zones have different read densities in each zone. Similar cylinder groups exist for the remaining available cylinders. As a result, the number of unusable cylinders, including system data, constitutes a spare zone 280.

3 is a block diagram showing several source zones 310, 330 and 350 after the head of the disk drive is frequency tuned. Frequency adjustment of the head creates subzones for each zone. Subzones are created at different read frequencies at which the various heads operate. For example, if one head is determined to be insufficient execution head, each zone will contain two subzones. The subzone 00 will have information recorded at the first frequency and the subzone 01 will have information recorded at the frequency adjusted head frequency. As shown in Fig. 3, the zone will be divided into N subzones. The maximum number N of subzones will be equal to the maximum number of heads 210 of the disk drive 100. In other words, each head record at a different frequency will have its own subzone. Primitive zones are numbered 0, 1, ..., n. In an embodiment, the source zone 310 corresponds to the source zone (0) 230 of FIG. 4. Similarly, primitive zone (1) 330 corresponds to primitive zone (1) 240 of FIG. 4 and in this way zone (n) 350 of FIG. 5 corresponds to zone n of FIG. 4. . Each one of the original zones is divided into corresponding sub-zones 320, 340 and 360. In an embodiment, zone (0) 310 is a zone specific number order state, i.e. subzone 00, subzone 01, subzone 03, subzone 04, ..., subzone ( It has several subzones 320 sorted by zone identification of zero followed by 0n). Thus, the subzone 00 corresponds to the original zone 0 which is the subzone 0. Similarly, subzone 01 corresponds to original zone 0, which is subzone 1.

Zone (1) 330 has a subzone structure 340, where the zone identifier is one. Therefore, the zones 1 and 330 are divided into subzones 10, subzones 11, subzones 12, subzones 13, ..., subzones 1n. Additional zones and subzones are in the spirit of the present invention and are described as zones (N) 350 that are divided into NN subzones 360. In another embodiment, several subzones can be integrated into one, minimizing the total number of zones maintained by hardware and software. In another embodiment, consider a drive with a total of five heads that reads information from a disk 134 formatted with four raw zones and twelve tracks from twelve cylinders. Of course, the actual disk drive 100 will have more tracks and cylinders. Disk drives typically have even heads. If two of the five heads are tuned to a single low frequency, the four source zones are divided into two subzones. Each raw zone is divided into two subzones, one set of subzones acting as the first three logical heads on all cylinders, and another set of subzones acting as the next two logical heads on all cylinders. to be. In another embodiment, if the frequency of the frequency adjusted head is 0.5% lower for all zones of the original zone, then the original zone is divided into a total of eight subzones.

6 is a graph of frequencies in bit density for various zones and subzones. The zone graph 400 has a horizontal axis 402 composed of sequentially numbered source zones (zones (0) through zones (N)), and has increasing bit density with units of megabits per second (MB / s). It has a vertical axis 404 that represents. Zone (0) is the outermost zone and zone (n) contains the user information as the innermost zone. When the recording density of the zone decreases, a stepped function 406 occurs. Typically, at the outer diameter of the disk, which is zone 0, the highest frequency or bit density is recorded. Similarly, subzones of corresponding primitive zones are graphed along horizontal and vertical axis arrangements 472 and 474, respectively, and may have similar stepped responses 476 and 478. As shown in FIG. 6, the subzone 01 corresponds to an element of the raw zone 0 (such as the primitive zone 310 shown in FIG. 5) and the subzone of FIG. 01). However, one different point of the subzone graph 470 is that the same primitive zone collection 478 is lower than the other subzones in the same primitive collection 476 because there is a lower recording rate for a given head in the zone. Will have a bit density. In the above embodiment, one of the subzones has a higher head service load than the other set. Thus, it may be advantageous to align the subzones in descending (head service load) order as shown in FIG. 6.

Due to the order of the sub zones based on the head load, the maintained data transfer rate gradually decreases as the zone itself gradually decreases in bit density from the high density zone to the low density zone. However, the data transfer rate will increase as the zone expands toward the subzone 30 and enters the subzone 01, and then gradually decreases again. Due to the inclusion of lower execution heads, subzones (0-1) 477 will have lower bit densities than subzones (0-0) in the same source zone. The algorithm will be used to view and sort the subzones.

Since the head is still at the outer diameter, it can be a high bit density, but not as high as the density of a good head. In addition, the head in the new zone has a much higher density than the good head of the disc inner diameter. The frequency for good run at the lower run heads thus far depends on production considerations.

Another embodiment of the present invention is directed to a method of reusing a lower execution read / write head by changing the frequency of the read / write head in the cylinder. This invention determines the physical location of the target logical block address. One form of arithmetic logic unit (ALU) requires that the number of heads be known to translate a given LBA. As a result, the zone table is used to determine the target zone and the number of heads served by the zone. The firmware searches the zone table to determine the zone of the target LBA. Once the target zone is determined, the number of heads served by the zone may be determined based on the position in the zone table (in frequency alignment and head load alignment method). An alternative could use the ALU alignment itself to identify the zone to identify the number of heads.

Using the number of previously determined heads as input, the ALU resources can be reused to calculate the physical sector, head and cylinder positions of the target LBA. The number of heads returned by the ALU is the number of frequency adjusted heads in the subzone. If the target LBA is in a frequency adjusted head zone, the number of frequency adjusted heads will have to be adjusted.

In FIG. 7, a hatched portion of a logical block address (LBA) diagram 500 for sequential read / write access is shown. The grid layout is similarly configured as shown in FIG. That is, a user track in a single cylinder is accessed by the head until an extra track has crashed or this track is no longer available for access. In one embodiment, several user tracks are accessed according to three unfrequency heads (heads 0, 1 and 2) 510. Because of this, the unfrequency tuned heads (heads 0, 1, and 2) 510 sequentially access other tracks within other cylinders until all groups of cylinders known as zones are accessed. Within this example, all untuned subzones are accessed for the first time starting at cylinder 0 and proceeding to cylinder n. Finally, all frequency adjusted subzones 520 are accessed by frequency adjusted heads (heads 3 and 4) 512. Readings for all frequency adjusted heads start at cylinder 0 and proceed to cylinder n. In one embodiment, the addressing diagram has a reserved zone. The reserved zone does not store user data, including system data, independently in the cylinder. In one embodiment, the frequency adjustment of the head does not occur in the reserved zone. All heads of the reserved cylinders will share the same frequency to avoid firmware complexity in handling the frequency adjusted heads in the reserved zone.

Thus, according to the example shown in FIG. 7, the original zone is divided into sub zones. In this embodiment, the LBA diagram is optimized to read large amounts of data sequentially and with less disturbance. When reading the disk 134 in the embodiment shown in Fig. 5, all unregulated heads read all information in the unregulated head state. Thus, the actuator moves from the outer diameter to the inner diameter and from one neighboring cylinder to the next. Access time is minimized. The time spent at the switching frequency in the recording channel is also minimized. Next, the actuator is returned to cylinder 0 and the data is read from all frequency adjusted heads in a similar manner. Again, access is minimized because movement moves from cylinder to neighboring cylinders. Frequency switching is also minimized. Resolution runs are larger using specific LBA diagrams.

8 shows an LBA diagram in which all subzones of a primitive zone are accessed before accessing a subzone of another primitive zone. First, the non-tuned head of the zone, then the frequency-adjusted head of the same zone (a separate zone of the original zone) is accessed. All subzones of the original zone are read before moving to another zone. This is known as serpentine-by-head and is based on a frequency adjusting head. The reserved zone for system data is also present in FIG. 8, similar to the reserved zone of FIG. In the embodiment shown in FIG. 8, the LBA diagram is constructed in a serpentine-like manner because the frequency adjusting head subzone is mixed with the unfrequency adjusted head subzone. Such LBA diagrams are suitable for accessing small data segments and require more access time than the sequential LBA diagram of FIG. However, resolution execution may suffer from frequent access disturbances, sometimes referred to as seek times (ie, time increases to obtain undisturbed information). Increased access time is described as repeatedly accessing a high density zone prior to the low density zone.

Embodiments In a headerless format where a data segment has a data segment, the format map is typically located in RAM to identify the drive where a sector is located on each track and eventually which sector is marked for lower performance.

9 is a flowchart 700 of an embodiment that provides a method for improving the error rate of a disk drive having a read / write head. The method includes a disk assembly for transducing data at a first frequency (block 720), transducing data at a second frequency (730), dividing a zone into subzones (block 740) and configuring a zone (block 750). Determining the storage face of block 715).

10 is a schematic diagram of a computer system. Preferably, the present invention is well suited to the user in computer system 2000. Computer system 2000 may also be referred to as an electronic system or information handling system and is a system bus 2030 for communicatively coupling with central processing unit 2004, memory and central processing unit 2004, and random access memory 2032. ). The information handling system 2002 comprises a disk drive device comprising the lamp described above. The information handling system 2002 may include an input / output bus 2010 and several peripheral devices such as 2012, 2014, 2016, 2018, 2020 and 2022 may be added to the input / output bus 2010. Peripherals include hard disk drives, magneto optical drives, floppy disk drives, monitors, keyboards, and other peripherals. Computer system 2000 operates as a standalone computer system and operates in a networked environment that uses logical connections to one or more remote computers. Certain types of disk drives may use a method of loading or unloading sliders onto the disk surface as described above.

Preferably, the described method for changing the recording frequency on the head base in the cylinder of the disc drive is particularly well performed in a headerless structure environment. The performance of low performance heads can be improved. In addition, an improved error rate is achieved to overcome the computational problem. The present invention may allow for improved precision of arithmetic logic unit (ALU) calculations without changing the engine for performing the calculations. In addition, there is little abandonment or rework of the entire drive as a result of the low execution head.

conclusion

It is a feature of the present invention to provide a method of improving the reading and writing of information for a disk drive having a read / write transducer. The method comprises data transducing at a first frequency when in the first zone of the first storage face of the disc assembly and a different frequency than the first frequency when accessing the first raw zone of the second storage face of the disc assembly. Transducing the data at two frequencies. The dividing step extends the first raw zone structure to subzones, and also maintains a parameter for each subzone representing the number of heads associated with the subzone.

In an embodiment of the described method, the number of heads is maintained as a zone specific parameter. In another embodiment, several subzones are integrated into one. In another embodiment, one subzone constituting from a zone has a different bit density than another subzone constituting from the same subzone.

In an embodiment of the method described above, dividing the subzones includes comparing the number of sectors in the nominal transducer domain with the total number of sectors in the frequency adjusted transducer domain and in the nominal transducer domain. Use a nominal transducer domain where the total number of sectors is significantly greater than the total number of sectors in the frequency tuned transducer domain. Another embodiment of the method described above comprises the steps of incorporating zones, using the recorded frequencies of the subzones, comparing the recording densities of one nominal subzone with successive nominal subzones, and a cylinder switch. Analyzing whether it is offset.

Another feature of the present invention provides an improved disk drive. The disk drive includes a rotating disk assembly having a first disk face and a second disk face. The disk drive includes a first head operating in a transducing relationship for the first disk plane and at a first frequency in the first disk raw zone and in a transducing relationship for the second disk plane but in the first raw disk zone. And a second head operating at a frequency different from the first frequency. In addition, the aforementioned first zone comprises the same radius range of the corresponding track on each storage surface. In one embodiment of the disk drive, the first zone is divided into a plurality of subzones, the first subzone being associated with the first head and the second subzone being associated with the second head. In an embodiment of the disc drive, the predetermined frequency of the sub zones is selected such that the associated first head and the second head perform an increased execution. Another embodiment of the present invention provides an alignment method wherein the first and second sub-zones are aligned based on the head rod. Another embodiment provides an alternative alignment method wherein the first and second subzones are aligned based on frequency.

Another feature of the present invention includes a magnetic disk storage system that includes a magnetic disk having a recording surface positioned approximately at a read / write transducer. The record / read transducer reads and records the information on the record side. At the same time, the memory is coupled within the disk storage system and similarly coupled to the read / write transducer. The memory contains the offset value of the servo position and the controller is coupled within the disk storage system. The controller, memory and read / write transducer are combined. Moreover, the controller places the read / write transducer in the disk storage system as a result of the input based on the number of frequency adjusted heads, where the frequency adjusted heads are heads operated at low frequencies. The described magnetic disk storage system includes a data segment having a headerless format.

Another embodiment of the described system includes a primitive zone that includes the same radius range of the corresponding track and each of a plurality of such zones on each storage surface. As a result, the subzone is part of the original zone that includes the same radius range of the corresponding track of each storage surface. In an embodiment of the described system, the information handling system is effectively coupled to transfer data to or from the magnetic disk with an input / output system that is effectively coupled to input and output data for the information handling system, and eventually to the information handling system. It includes a combined memory.

In addition, another feature of the present invention provides a system for reusing a low performance read / write head. A system that reuses low performance read / write heads includes a plurality of write zones for storing data between write zones. Thus, the error rate caused by the low execution read / write head is significantly improved. In addition, a plurality of read / write heads for reading and writing data on a storage medium, a plurality of cylinders for adjusting read / write head frequency changes, and a zone table for determining the number of heads served by a target zone and zone have. In another embodiment, the ALU resource is used to identify the number of heads associated with the zone and the system described above. In another embodiment, the ALU resource calculates the physical sector, head and target LBA to be frequency adjusted head count in the subzone.

Another feature of the invention is a disc drive comprising a disc having a first side further comprising a first zone and a second zone. Similarly, the disc drive has a second side further comprising a first zone and a second zone, wherein the track of the first zone of the second side coincides with the track of the first zone of the first side. In addition, the disk drive includes means for minimizing the error rate in one of the first zones.

While the foregoing has been described, it should be understood that it is not limited. Many other embodiments will be apparent to those skilled in the art upon review of the foregoing. Accordingly, the spirit of the invention will be determined with reference to the appended claims, along with all the spirit of the scope of the claims.

Claims (22)

A method for improving reading and writing information to a disk drive, the disk drive having a read / write transducer, the disk drive comprising a disk assembly having at least a first storage surface and a second storage surface, The first storage surface and the second storage surface are formatted with at least a first raw zone and a second raw zone, the first raw zone comprising an equivalent range of a corresponding track on the respective storage surfaces; In the record improvement method, (a) transducing information at a first frequency when in the first source zone of the first storage surface; And (b) transducing information at a second frequency that is different from the first frequency when in the first source zone of the second storage surface of the disk assembly. The method of claim 1, (c) dividing the first source zone into at least two subzones. 3. The method of claim 2, wherein for each of the read / write transducers, the dividing step (c) further comprises maintaining a parameter for each subzone indicating the number of transducers associated with the subzones. How to. 4. The method of claim 3, wherein the dividing step (c) further comprises configuring one subzone starting from one zone according to a bit density value different from other subzones starting from the same zone. How to. The method of claim 1, wherein the dividing step (c) comprises: (c) (i) comparing the total number of sectors in the frequency adjusted transducer domain with a plurality of sectors in the nominal transducer domain; And (c) (ii) further comprising using the nominal transducer domain with a total number of sectors in the nominal transducer domain significantly higher than the total number of sectors in the frequency adjusted transducer domain. . The method of claim 1, (d) configuring the subzone, The sub zone configuration step, (d) (i) using the recording frequency of the subzone; (d) (ii) comparing the recording density of one nominal subzone with the next nominal subzone; And (d) (iii) analyzing whether the cylinder switch is offset. In the disk drive, A rotating disk assembly having a first disk surface and a second disk surface; A first transducer operating in a transducing relationship with the first disk surface at a first frequency in a first disk source zone; And A second transducer operating in a transducing relationship with the second disk surface at a frequency different from the first frequency when operating in the first raw disk zone, the first zone corresponding to each storage surface. A disc drive comprising an equivalent radius range of a track. 8. The disk drive of claim 7, wherein the first zone is divided into a plurality of sub zones, the first sub zone is associated with a first transducer and the second sub zone is associated with a second transducer. 10. The method of claim 8, wherein at least one of the frequencies of one subzone has increased data quality performance compared to the other of the associated first and second transducers, wherein one of the associated first and second transducers is present. Characterized in that it is selected. 9. The disk drive of claim 8, wherein the first and second sub-zones are classified based on transducer rods. 9. The disk drive of claim 8, wherein the first and second sub-zones are classified based on frequency. In a magnetic disk storage system, A magnetic disk assembly having at least first and second recording surfaces; A read / write transducer positioned proximate to a first recording surface of the magnetic disk for reading and writing information on the first recording surface; A memory coupled within the disk storage system and coupled to the read / write transducer, the memory comprising an offset value of a servo position; And A controller coupled within the disk storage system and coupled to the read / write transducer and a memory, the controller storing the disk through a target address as a result of input based on a total number of optimized transducers. Positioning a read / write transducer within the system, wherein the optimized transducer is a transducer operating at a low frequency. 13. The magnetic disk storage system of claim 12, wherein the data segment recorded on the first recording surface has a headerless format. 13. The magnetic disc of claim 12, wherein the raw zone formatted on the first and second recording surfaces includes an equivalent radius range of a corresponding track on each of the storage surfaces, the plurality of zones being predetermined. Storage system. 15. The magnetic disk storage system of claim 14, wherein the subzone is a division of the primitive zone including an equivalent radius range of the corresponding track on the respective storage surfaces. The method of claim 12, An information processing system coupled to transfer data to and from the magnetic disk; An input / output subsystem coupled to input and output data to the information processing system; And And a memory coupled to the information processing system. A system for reusing a sub-period read / write transducer, the system comprising: A plurality of recording zones for storing data having a change in frequency among the plurality of recording zones to improve the error rate caused by the lower performing read / write transducer; A plurality of read / write transducers for reading and writing information on the storage medium; A plurality of cylinders for receiving read / write transducer frequency changes; And And a zone table for determining the number of transducers serviced by the zone and the target zone. 18. The system of claim 17, wherein an arithmetic logic unit (ALU) resource is used to identify the number of zones and transducers. 19. The system of claim 18, wherein the ALU resource calculates cylinder positions of physical sectors, transducers, and target block addresses (LBAs) to form a frequency regulated number of transducers within a subzone. In the disk drive, A disk having a first surface comprising a first zone and a second zone; A second face comprising a first zone and a second zone, the track of the first zone of the second face corresponding to the track of the first zone of the first face; And And means for minimizing an error rate in one of the first zones. In the disk drive, First and second read / write transducers; And And a disk assembly having a first storage surface in a transducing relationship with the first read / write transducer and a second storage surface in a transducing relationship with the second read / write transducer. 2 a storage surface is formatted with at least a first zone and a second zone, said first zone comprising an equivalent range of corresponding tracks on said respective storage surfaces, wherein a first amount of data is a first zone of said first storage surface And a second amount of data that is different from the first amount of data is written to the first zone of the second storage surface. 22. The disk drive of claim 21, wherein the first zone is divided into a plurality of subzones, the first subzone is associated with a first transducer, and the second subzone is associated with a second transducer. .