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Fujitsu MHT2040BH, MHT2060BH, MHT2080BH Caching operation, Commands that are targets of caching

Models: MHT2080BH MHT2060BH MHT2040BH

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Operations

6.4.2 Caching operation

The caching operation is performed only when the commands listed below are received. If any of the following data are stored on the data buffer, the data is sent to the host system.

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•

All of the sector data that this command processes.

A part of the sector data including the start sector, that this command processes.

If part of the data to be processed is stored on the data buffer, the remaining data is read from disk media and sent to the host system.

(1) Commands that are targets of caching

The commands that are targets of caching are as follows:

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•

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READ SECTOR (S) (EXT)

READ MULTIPLE (EXT)

READ DMA (EXT)

READ FP DMA QUEUED

However, if the caching function is prohibited by the SET FEATURES command, the caching operation is not performed.

(2) Data that is a target of caching

The data that is a target of caching are as follows:

1)Read-ahead data that is read from disk media and saved to the data buffer upon completion of execution of a command that is a target of caching.

2)Pre-read data that is read from disk media and saved to the data buffer before execution of a command that is a target of caching.

3)Data required by a command that is a target of caching and has been sent to the host system one. If the sector data requested by the host has not been completely stored in the read cache portion of the buffer, this data does not become a target of caching. Also, If sequential hits occur continuously, the caching-target data required by the host becomes invalid because that data is overwrited by new data.

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Fujitsu MHT2040BH, MHT2060BH Caching operation, Commands that are targets of caching, Data that is a target of caching

Contents

MHT2080BH, MHT2060BH, MHT2040BH Disk Drives Product ManualFor Safe Operation Handling of This ManualRevision History This page is intentionally left blank Preface Overview of ManualOperating Environment Conventions for Alert MessagesConventions Liability Exception This page is intentionally left blank Important Alert Items Important Alert MessagesThis page is intentionally left blank Manual Organization MHT2040BH Disk Drives Maintenance ManualMHT2040BH Disk Drives Product Manual This page is intentionally left blank Contents Installation Conditions Theory of Device OperationInterface 102 Operations Acronyms and Abbreviations AB-1 GL-1IN-1 Illustrations FiguresResponse to power-on when the host is powered Recommended connector specifications for the host system TablesRelationship between combination of Identifier and Security Device Overview Functions and performance FeaturesAdaptability Interface Specifications 1/2 Device SpecificationsSpecifications summary MHT2080BH MHT2060BH MHT2040BHMHT2080BH Specifications 2/2Model and product number Examples of model names and product numbersInput Voltage Power RequirementsRipple 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 Host-initiated Interface Power Management Hipm Interface Power Management IPMDevice-initiated Interface Power Management Dipm Interface power management This page is intentionally left blank Device Configuration Device Configuration Drive connection System ConfigurationSata interface Read/write circuitThis page is intentionally left blank Installation Conditions Dimensions DimensionsIntegration Guidance C141-E144 MountingOrientation Limitation of mounting FramePCA Location of breather Ambient temperature Service area Handling cautionsSumitomo 3M ESDHios Device connector Connections with Host SystemSignal segment and power supply segment Connector specifications for host systemRecommended connector specifications for the host system Sata interface cable connection This page is intentionally left blank Theory 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 RLL code MeeprmlAGC circuit Read circuitProgrammable filter circuit D converter circuit Digital PLL circuitFIR circuit Viterbi detection circuitServo control circuit Servo ControlMicroprocessor unit MPU A converter DAC Power amplifierServo burst capture circuit Spindle motor control circuitData area Data-surface servo formatInner guard band IGB Outer guard band OGBPhysical sector servo configuration on disk surface Servo frame format Seek operation Actuator motor controlOperation to move the head to the reference cylinder Track-following operationAcceleration mode Start modeSpindle motor control Stable rotation mode This page is intentionally left blank Interface Interface signals Physical InterfaceComwake Comreset / Cominit5VDC/GND Signal interface regulation Out of band signalingPrimitives descriptions Electrical specifications Physical Layer Electrical Requirements 1/2Physical Layer Electrical Requirements 2/2 COMRESET/COminit Connector pinouts Connector pinoutsConceptual diagram of communication layers Logical InterfaceLink layer Communication layersPhysical layer Transport layerOutline of the Shadow Block Register Shadow Block RegisterRegister Host to Device Outline of the frame information structure FISFIS types Register Host to Device FIS layoutRegister Device to Host DMA Active Device to HostDMA Setup Device to Host or Host to Device Bidirectional TAGBist Active Bidirectional Bist combinationsData Host to Device or Device to Host Bidirectional Data FIS Bidirectional layoutShadow block registers Error FieldUNC Sector Number Field exp Features Field expSector Count Field exp Cylinder Low Field expHS3 HS2 HS1 HS0 Cylinder High Field expDevice/Head Field HS3Status field Bit Device Write Fault DF bitBit Error ERR bit Bit 7 Busy BSY bitDevice Control Field Command FieldBit 2 Software Reset Srst EStatus FieldCommand code and parameters Host CommandsCommand code and parameters 1/3 Command code and parameters 2/3 Command code and parameters 3/3 Command descriptions Error reporting conditions Recalibrate X’10’ to X’1F’Read Sectors X’20’ or X’21’ LBA LSB LBARead Long X’22’ or X’23’ Write Sectors X’30’ or X’31’ 00 *1 Error information Write Long X’32’ or X’33’ Cylinder No. LSB Write Verify X’3C’ Host Commands Read Verify Sectors X’40’ or X’41’ Host Commands Seek X’70’ to X’7F’ Execute Device Diagnostic X’90’ Diagnostic codeInitialize Device Parameters X’91’ Download Microcode X’92’ Operation of Download MicrocodeError reporting conditions Standby Immediate X’94’ or X’E0’ Idle Immediate X’95’ or X’E1’ Standby X’96’ or X’E2’ Idle X’97’ or X’E3’ Host Commands Check Power Mode X’98’ or X’E5’ ’FF’Comreset Sleep X’99’ or X’E6’Smart X’B0’ Features Field values subcommands and functions 1/3 Smart Disable Operations Features Field values subcommands and functions 2/3Smart Enable Operations Smart Read LOG’DB’ Smart ENABLE/DISABLE Auto OFF-LINE Features Field values subcommands and functions 3/3Smart Return Status Key C2h 10 Format of device attribute value data 11 Format of guarantee failure threshold value data1FF Data format version number Attribute IDAttribute value for the worst case so far Status FlagCurrent attribute value Raw attribute valueSelf-test execution status 12 Off-line data collection status13 Self-test execution status 14 Off-line data collection capability 16 Drive error logging capability15 Failure prediction capability flag Checksum Guarantee failure thresholdSmart error logging 17 Log Directory Data Format18 Data format of Smart Summary Error Log 1/2 Error data structure 18 Data format of Smart Summary Error Log 2/2Command data structure Total number of drive errors19 Data format of Smart Comprehensive Error Log Smart Self-TestSelf-test number 20 Smart self-test log data format1FC Self-test indexTest Span 21 Selective self-test log data structureCurrent LBA under test Current Span under test Feature Flags22 Selective self-test feature flags Selective Self-test pending time minDevice Configuration Freeze Device Configuration XB1Device Configuration Restore Device Configuration IdentifyDevice Configuration Restore Features Field = C0h Device Configuration Freeze Lock Features Field = C1hDevice Configuration Identify Features Field = C2h Device Configuration SET Features Field = C3h23 Device Configuration Identify data structure Word Value ContentRead Multiple X’C4’ Execution example of Read Multiple command LBA LSB Write Multiple X’C5’ At command issuance Shadow Block Registers setting contents SET Multiple Mode X’C6’ Host Commands Read DMA X’C8’ or X’C9’ LBA Write DMA X’CA’ or X’CB’ Host Commands Read Buffer X’E4’ Flush Cache X’E7’ Write Buffer X’E8’ Identify Device X’EC’ Identify Device DMA X’EE’ 24 Information to be read by Identify Device command 1/3 ’3FFF’24 Information to be read by Identify Device command 2/3 24 Information to be read by Identify Device command 3/3 Interface Bit 0 Reserved C141-E203-01EN FIS Host Commands Word Bit Bit 0 1 = Supports the Mode C141-E203-01EN Interface SET Features X’EF’ 25 Features field values and settable modes 1/225 Features field values and settable modes 2/2 Data Transfer Mode Advanced Power Management APM Serial ATA Functions Automatic Acoustic Management AAM26 Contents of Security SET Password data Error reporting conditions When the user password is selected When the master password is selectedSecurity UNLOCKX’F2’ Host Commands Security Erase Prepare X’F3’ Security Erase Unit X’F4’ Security Freeze Lock X’F5’ Error reporting conditions 28 Contents of security password Error reporting conditions Read Native MAX Address X’F8’ LbalsbSET MAX X’F9’ SET MAX AddressSET MAX SET Password Features Field = 01h Password information SET MAX Lock Features Field = 02h SET MAX Unlock Features Field = 03h SET MAX Freeze Lock Features Field = 04h CL EXP Read Sector S EXT X’24’ DescriptionSN EXP Read DMA EXT X’25’ Description Read Native MAX Address EXT X’27’ Read Multiple EXT X’29’ Read LOG EXT X2F CL EXP SN EXP 29 Data format of Read Log Ext log page 10h 30 Tag field informationWrite Sector S EXT X’34’ Description Write DMA EXT X’35’ Description SET MAX Address EXT X’37’ SET MAX LBA Write Multiple EXT X’39’ Write LOG EXT X3F Error information 132 C141-E203-01EN Read Verify Sector S EXT X’42’ Flush Cache EXT X’EA’ Write Multiple FUA EXT XCE Write DMA FUA EXT X3D Read FP DMA Queued Write FP DMA Queued Command Name Error posting31 Command code and parameters 1/2 Sfrw Sfrr31 Command code and parameters 2/2 Non-data command protocol Command ProtocolExecute Device Diagnostic Initialize Device Parameters Host PIO data-in command protocol PIO data-out command protocol Piosu Data12 PIO data-out command protocol PiosuDMA data-in command protocol Read DMA EXT Identfy DMADMA data-out command protocol Write DMA EXT FUA EXTNative Command Queuing protocol Read FP DMA Queued Write FP DMA Queued15 Read FP DMA Queued command protocol 16 Write FP DMA Queued command protocol Power-on and Comreset 17 Power-on sequence18 Comreset sequence Operations Reset and Diagnosis Response to power-onReset and Diagnosis Response to Comreset Response to ComresetResponse to a software reset Response to a software resetActive mode Power SavePower save mode Active idle modeStandby mode Sleep modePower commands Power save mode of the interface Interface Power SavePartial mode Slumber mode Data buffer structure Read-ahead Cache8MB buffer Caching operation Commands that are targets of cachingData that is a target of caching Invalidating caching-target data Using the read segment buffer Miss-hitSequential hit Full hitHAP end location of the previous read command Partial hit Cache operation Command that are targets of cachingWrite Cache Invalidation of cached dataCashing function when power supply is turned on Status report in the event of an errorComreset and software reset response Enabling and disablingThis page is intentionally left blank Glossary PIO Programmed input-output Power save modeRotational delay PositioningAcronyms and Abbreviations This page is intentionally left blank Block diagram IndexIndex Device-initiated interface power Frame information structure FIS Moving head to reference cylinder .4-13 Read Native MAX Address RLL algorithm run length limitedSensing and compensating for IN-8 C141-E203-01EN Disk Drives Product Manual Comment FormJapan This page is intentionally left blank C141-E203-01EN This page is intentionally left blank