Fujitsu MHV2060AT Actuator motor control, Operation to move the head to the reference cylinder

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Theory of Device Operation

4.7.4 Actuator motor control

The voice coil motor (VCM) is controlled by feeding back the servo data recorded on the data surface. The MPU fetches the position sense data on the servo frame at a constant interval of sampling time, executes calculation, and updates the VCM drive current.

The servo control of the actuator includes the operation to move the head to the reference cylinder, the seek operation to move the head to the target cylinder to read or write data, and the track-following operation to position the head onto the target track.

(1) Operation to move the head to the reference cylinder

The MPU moves the head to the reference cylinder when the power is turned. The reference cylinder is in the data area.

When power is applied the heads are moved from the outside of media to the normal servo data zone in the following sequence:

a)Micro current is fed to the VCM to press the head against the outer direction.

b)The head is loaded on the disk.

c)When the servo mark is detected the head is moved slowly toward the inner circumference at a constant speed.

d)If the head is stopped at the reference cylinder from there. Track following control starts.

(2) Seek operation

Upon a data read/write request from the host, the MPU confirms the necessity of access to the disk. If a read/write instruction is issued, the MPU seeks the desired track.

The MPU feeds the VCM current via the D/A converter and power amplifier to move the head. The MPU calculates the difference (speed error) between the specified target position and the current position for each sampling timing during head moving. The MPU then feeds the VCM drive current by setting the calculated result into the D/A converter. The calculation is digitally executed by the firmware. When the head arrives at the target cylinder, the track is followed.

(3) Track following operation

Except during head movement to the reference cylinder and seek operation under the spindle rotates in steady speed, the MPU does track following control. To position the head at the center of a track, the DSP drives the VCM by feeding micro current. For each sampling time, the VCM drive current is determined by filtering the position difference between the target position and the position clarified by the detected position sense data. The filtering includes servo compensation. These are digitally controlled by the firmware.

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C141-E218

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Contents MHV2120AT, MHV2100AT, MHV2080AT MHV2060AT, MHV2040AT Disk Drive Product ManualFor Safe Operation Handling of This ManualRevision History This page is intentionally left blank Preface Overview of ManualConventions Conventions for Alert MessagesOperating Environment Liability Exception This page is intentionally left blank Damage Interface cable connection Important Alert ItemsImportant Alert Messages This page is intentionally left blank Disk Drive Product Manual Disk Drive Maintenance ManualManual Organization This page is intentionally left blank Contents Installation Conditions Theory of Device OperationContents Interface101 Write Multiple EXT X’39’ Option customizing Operations Glossary GL-1 Acronyms and Abbreviations AB-1 Index IN-1 Illustrations FiguresExecution example of Read Multiple command Surface temperature measurement points and standard Tables25 Relationship between combination of Identifier This page is intentionally left blank Device Overview Adaptability FeaturesFunctions and performance Connection to ATA interface Error correction and retry by ECCHigh resistance against shock Data bufferSpecifications 1 Device SpecificationsSpecifications summary Examples of model names and product numbers Specifications 2Model and product number Ripple Power RequirementsInput Voltage Current Requirements and Power Dissipation Current and power dissipationPower on/off sequence Environmental SpecificationsCurrent fluctuation Typ. at +5 V when power is turned on Environmental specificationsAcoustic Noise Acoustic noise specificationShock and vibration specification Shock and VibrationReliability Service lifeData assurance in the event of power failure Mean time between failures MtbfPositioning error Error RateUnrecoverable read error Media DefectsAdvanced Power Management Advanced Power Management Advanced Power ManagementThis page is intentionally left blank Device Configuration Device Configuration 2 1 drive connection System ConfigurationATA interface Read/write circuit2 drives configuration 3 2 drives connectionInstallation Conditions Dimensions DimensionsOrientation MountingIntegration Guidance C141-E144 PCA FrameLimitation of mounting Location of breather Ambient temperature Service area Handling cautionsHandling cautions Device connector Cable ConnectionsDevice connection Cable connector specificationsCable connector specifications FCILocation of setting jumpers Jumper SettingsPower supply connector CN1 Factory default setting Master drive-slave drive settingCsel setting 14 Csel settingPower up in standby setting 16 Example 2 of cable selectTheory of Device Operation Disk OutlineSubassemblies SpindleServo circuit Circuit ConfigurationAir filter Spindle motor driver circuitPower supply configuration PCA Power-on Sequence Power-on operation sequenceSelf-calibration contents Self-calibrationCommand processing during self-calibration Execution timing of self-calibrationWrite circuit Read/write CircuitRead/write preamplifier PreAMP Write precompensationProgrammable filter circuit Read circuitAGC circuit D converter circuit Digital PLL circuitFIR circuit Viterbi detection circuitServo Control Servo control circuitServo burst capture circuit Power amplifierMicroprocessor unit MPU A converter DACDriver circuit VCM current sense resistor CSRData area Data-surface servo formatInner guard band Outer guard bandPhysical sector servo configuration on disk surface Servo frame format Seek operation Actuator motor controlOperation to move the head to the reference cylinder Track following operationStable rotation mode Start modeAcceleration mode Spindle motor controlThis page is intentionally left blank Interface Interface signals Physical InterfaceDA1 PDIAG-, Cblid DA0 DA2 Signal assignment on the connectorSignal assignment on the interface connector Dasp GNDStop MstrDiow DiorDasp PdiagCblid IordyLogical Interface DA2 DA1 DA0 1 I/O registersI/O registers Data register X’1F0’ Command block registersError register X’1F1’ UNC IdnfSector Count register X’1F2’ Features register X’1F1’SET Multiple Mode Cylinder High register X’1F5’ Sector Number register X’1F3’Cylinder Low register X’1F4’ Status register X’1F7’ Device/Head register X’1F6’DEV HS3 HS2 HS1 HS0 BSYInterface Alternate Status register X’3F6’ Command register X’1F7’Control block registers Device Control register X’3F6’ Host CommandsCommand code and parameters HOB SrstCommand code and parameters 1 Parameter UsedCommand code and parameters 2 EXT Write Multiple FUA EXT Flush Cache EXTHost Commands Command descriptions Host Commands Recalibrate X’10’ to X’1F’ Read Sectors X’20’ or X’21’ MSBEnd head No. / LBA MSB Write Sectors X’30’ or X’31’ 1F7HST Status information 1F6HDH Write Verify X’3C’ Read Verify Sectors X’40’ or X’41’ Seek X’70’ to X’7F’ Execute Device Diagnostic X’90’ Diagnostic codeHost Commands Initialize Device Parameters X’91’ Download Microcode X’92’ Operation of Download Microcode Standby Immediate X’94’ or X’E0’ Unload Feature Unload Immediate Command Host Commands Standby X’96’ or X’E2’ Idle X’97’ or X’E3’ Interface Check Power Mode X’98’ or X’E5’ ’FF’Sleep X’99’ or X’E6’ Smart X’B0 Features register values subcommands and functions 1 Smart Disable Operations Features register values subcommands and functions 2Smart Enable Operations Smart Read LOGSmart Return Status Features register values subcommands and functions 3’DB’ Smart ENABLE/DISABLE Auto OFF-LINE Host Commands Format of insurance failure threshold value data Format of device attribute value data1FF Data format version number Attribute IDAttribute value for the worst case so far Status FlagCurrent attribute value Raw attribute value11 Self-test execution status 10 Off-line data collection statusSelf-test execution status Failure prediction capability flag Off-line data collection capability12 Off-line data collection capability 13 Failure prediction capability flagCheck sum Error logging capability14 Error logging capability Insurance failure thresholdSmart error logging 16 Data format of Smart Summary Error Log Total number of drive errors Command data structureError data structure 17 Data format of Smart Comprehensive Error Log1FC Smart self-test18 Smart self-test log data format Self-test numberCurrent LBA under test 19 Selective self-test log data structureTest span Current span under testSelective self-test pending time min Feature flags20 Selective self-test feature flags Device Configuration Freeze Device Configuration XB1Device Configuration Restore Device Configuration IdentifyDevice Configuration Identify FR = C2h Device Configuration Restore FR = C0hDevice Configuration Freeze Lock FR = C1h Device Configuration SET FR = C3hInterface 21 Device Configuration Identify data structure Interface Execution example of Read Multiple command Read Multiple X’C4’MSB Write Multiple X’C5’ Interface SET Multiple Mode X’C6’ Interface Read DMA X’C8’ or X’C9’ End head No. / LBA MSB Write DMA X’CA’ or X’CB’ Interface Read Buffer X’E4’ Flush Cache X’E7’ Write Buffer X’E8’ Identify Device X’EC’ Identify Device DMA X’EE’ 22 Information to be read by Identify Device command 1 ’3FFF’22 Information to be read by Identify Device command 2 Word Command without interrupt supports 2, 4, 8 and 16 sectors = Supports the Host Protected Area feature set = Supports the CFA Compact Flash Association feature set Interface Host Commands Interface Host Commands Word Bit Reserved Security level High, 1 Maximum ’BB’ SET Features X’EF’23 Features register values and settable modes ’CC’Data Transfer Mode Advanced Power Management APM Automatic Acoustic Management AAM 24 Contents of Security SET Password data At command issuance I-O register contents 1F7hCM Security UNLOCKX’F2’ When the master password is selectedWhen the user password is selected Interface Security Erase Prepare X’F3’ Security Erase Unit X’F4’ Security Freeze Lock X’F5’ At command issuance I-O register contents 1F7hCM 26 Contents of security password Interface Read Native MAX Address X’F8’ SET MAX X’F9’ SET MAX AddressSET MAX SET Password FR = 01h SET MAX Lock FR = 02h SET MAX Unlock FR = 03h SET MAX Freeze Lock FR = 04h Host Commands Read Sectors EXT X’24’ Option customizing Description Read DMA EXT X’25’ Option customizing Description Error reporting conditions Read Multiple EXT X’29’ Option customizing Description Read LOG EXT X2F Optional command Customize Description Host Commands Write Sectors EXT X’34’ Option customizing Description Write DMA EXT X’35’ Option customizing Description SET MAX Address EXT X’37’ Option customizing Description SET MAX LBA Write Multiple EXT X’39’ Option customizing Description Write DMA FUA EXT X’3D’ Option customizing Description Write LOG EXT X’3F’ Optional command Customize Description Host Commands Read Verify Sectors EXT X’42 Option customizing Description Write Multiple FUA EXT X’CE’ Option customizing Description Flush Cache EXT X’EA’ Option customizing Description Error posting 27 Command code and parameters 127 Command code and parameters 2 Execute Device Diagnostic Initialize Device Parameters Command ProtocolPIO Data transferring commands from device to host Read Sectors Command protocol Protocol for command abort PIO Data transferring commands from host to device Write Sectors command protocol Commands without data transfer Read Multiple EXT Write Multiple EXT/FUA EXT Sleep Other commandsDMA data transfer commands Read DMA EXT Write DMA EXT/FUA EXT Indentify Device DMANormal DMA data transfer Ultra DMA Feature Set OverviewInitiating an Ultra DMA data in burst Phases of operationUltra DMA data in commands Pausing an Ultra DMA data in burst Data in transferTerminating an Ultra DMA data in burst Ultra DMA Feature Set Interface Ultra DMA data out commands Initiating an Ultra DMA data out burstPausing an Ultra DMA data out burst Data out transferTerminating an Ultra DMA data out burst Interface Ultra DMA CRC rules DIOR-HDMARDY-HSTROBE Series termination required for Ultra DMA28 Recommended series termination for Ultra DMA DIOW-STOPPIO data transfer timing TimingPIO data transfer 10 Multiword DMA data transfer timing mode Multiword data transferUltra DMA data transfer 11 Initiating an Ultra DMA data in burstName Mode Comment Strobe29 Ultra DMA data burst timing requirements 2 MIN MAXMode Name Comment 30 Ultra DMA sender and recipient timing requirementsDD150 at device Dstrobe at host Sustained Ultra DMA data in burstDstrobe at device DD150 at hostDmack Host pausing an Ultra DMA data in burstDmarq HdmardyDevice terminating an Ultra DMA data in burst StopDA0, DA1, DA2 CS0, CS1 Host terminating an Ultra DMA data in burstHost 16 Initiating an Ultra DMA data out burst Hstrobe at device DD150 at device Sustained Ultra DMA data out burstHstrobe at host DD150 at host Hstrobe host DD150 Host Device pausing an Ultra DMA data out burstDevice DMACK- host Stop host DDMARDY- device Host terminating an Ultra DMA data out burst 19 Host terminating an Ultra DMA data out burstDD150 Host Device terminating an Ultra DMA data out burstDmarq device DMACK- host Only master device is present Power-on and resetMaster and slave devices are present 2-drives configuration Operations Device Response to the Reset Response to power-onResponse to hardware reset Response to power-onResponse to hardware reset Response to software reset Response to software resetResponse to diagnostic command Response to diagnostic commandActive mode Power SavePower save mode Active idle modeStandby mode Sleep modeSpare area Power commandsDefect Processing Track slip processing Alternating processing for defective sectorsSector slip processing Automatic alternating processing Automatic alternating processing8MB buffer 8,388,608 bytes Read-ahead CacheData buffer structure Data that is a target of caching Commands that are targets of cachingCaching operation Invalidating caching-target dataSmart Using the read segment buffer Miss-hitSequential hit Full hit Partial hit Cache operation Command that are targets of cachingWrite Cache Invalidation of cached dataCaching function when power supply is turned on Status report in the event of an errorReset response Enabling and disablingWrite Cache This page is intentionally left blank Glossary PIO Programmed input-output Power save modeRotational delay PositioningStatus VCMThis page is intentionally left blank Acronyms and Abbreviations This page is intentionally left blank Index AAMIndex Host terminating ultra DMA data Read Sectors Command Read Native MAX AddressSurface temperature measurement This page is intentionally left blank Comment Form JapanThis page is intentionally left blank MHV2120AT, MHV2100AT, MHV2080AT, MHV2060AT, MHV2040AT C141-E218-01ENThis page is intentionally left blank
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