Microprocessor unit MPU, A converter DAC | Fujitsu MHU2100AT

4.7 Servo Control

(1) Microprocessor unit (MPU)

The MPU executes startup of the spindle motor, movement to the reference cylinder, seek to the specified cylinder, and calibration operations. Main internal operation of the MPU are shown below.

The major internal operations are listed below.

a.Spindle motor start

Starts the spindle motor and accelerates it to normal speed when power is applied.

b.Move head to reference cylinder

Drives the VCM to position the head at the any cylinder in the data area. The logical initial cylinder is at the outermost circumference (cylinder 0).

c.Seek to specified cylinder

Drives the VCM to position the head to the specified cylinder.

d.Calibration

Senses and stores the thermal offset between heads and the mechanical forces on the actuator, and stores the calibration value.

(2) Servo burst capture circuit

The servo burst capture circuit reproduces signals (position signals) that indicate the head position from the servo data on the data surface. From the servo area on the data area surface, via the data head, the burst signal of SERVO A, SERVO B, SERVO C, and SERVO D is output as shown in Figure 4.8 in subsequent to the servo mark, gray code that indicates the cylinder position, and index information. The servo signals do A/D-convert by Fourier-demodulator in the servo burst capture circuit. At that time the AGC circuit is in hold mode. The A/D converted data is recognized by the MPU as position information with A-B and C-D processed.

(3) D/A converter (DAC)

The control program calculates the specified data value (digital value) of the VCM drive current, and the value is converted from digital-to-analog so that an analog output voltage is sent to the power amplifier.

(4) Power amplifier

The power amplifier feeds currents, corresponding to the DAC output signal voltage to the VCM.

C141-E202-01EN

4-13

Image 69

Fujitsu MHU2100AT manual Microprocessor unit MPU, Servo burst capture circuit, A converter DAC, Power amplifier

Contents

MHU2100AT Disk Drive Product Manual Handling of This Manual For Safe Operation Revision History This page is intentionally left blank Overview of Manual Preface Conventions for Alert Messages Operating EnvironmentConventions Liability Exception This page is intentionally left blank Important Alert Messages Important Alert Items This page is intentionally left blank MHU2100AT Disk Drive Maintenance Manual Manual OrganizationMHU2100AT Disk Drive Product Manual This page is intentionally left blank Contents Theory of Device Operation Installation Conditions Interface Contents 100 120 Operations Glossary GL-1 Acronyms and Abbreviations AB-1 Index IN-1 Figures Illustrations Execution example of Read Multiple command Tables Surface temperature measurement points and standard 25 Relationship between combination of Identifier This page is intentionally left blank Device Overview Features Functions and performanceAdaptability Connection to ATA interface Error correction and retry by ECCData buffer Read-ahead cache system Device Specifications Specifications summarySpecifications 1 Model and product number Specifications 2MHU2100AT Examples of model names and product numbers Power Requirements Input VoltageRipple Current and power dissipation Current fluctuation Typ. at +5 V when power is turned on Environmental SpecificationsPower on/off sequence Environmental specifications Shock and vibration specification Acoustic noise specificationAcoustic Noise Shock and Vibration Data assurance in the event of power failure Service lifeReliability Mean time between failures Mtbf Unrecoverable read error Error RatePositioning error Media Defects Advanced Power Management Advanced Power Management Advanced Power Management This page is intentionally left blank Device Configuration Device Configuration ATA interface System Configuration2 1 drive connection Read/write circuit 3 2 drives connection 2 drives configuration Installation Conditions Dimensions Dimensions Mounting Integration Guidance C141-E144Orientation Frame Limitation of mountingPCA Location of breather Ambient temperature Handling cautions Service area Handling cautions Cable Connections Device connector Cable connector specifications Cable connector specificationsDevice connection FCI Jumper Settings Power supply connector CN1Location of setting jumpers Master drive-slave drive setting Factory default setting 14 Csel setting Csel setting 16 Example 2 of Cable Select Power Up in Standby setting Theory of Device Operation Subassemblies OutlineDisk Spindle Air filter Circuit ConfigurationServo circuit Spindle motor driver circuit Power Supply Configuration PCA Power-on operation sequence Power-on Sequence Self-calibration Self-calibration contents Execution timing of self-calibration Command processing during self-calibration Read/write preamplifier PreAMP Read/write CircuitWrite circuit RLL code Meeprml Read circuit AGC circuitProgrammable filter circuit FIR circuit Digital PLL circuitD converter circuit Viterbi detection circuit Servo control circuit Servo Control Microprocessor unit MPU Power amplifierServo burst capture circuit A converter DAC Spindle motor control circuit Driver circuitVCM current sense resistor CSR Inner guard band Data-surface servo formatData area Outer guard band Physical sector servo configuration on disk surface Servo frame format Operation to move the head to the reference cylinder Actuator motor controlSeek operation Track following operation Acceleration mode Start modeStable rotation mode Spindle motor control Theory of Device Operation Interface Physical Interface Interface signals Signal assignment on the interface connector Signal assignment on the connectorDA1 PDIAG-, Cblid DA0 DA2 Dasp GND Diow MstrStop Dior Cblid PdiagDasp Iordy Logical Interface 1 I/O registers I/O registersDA2 DA1 DA0 Error register X’1F1’ Command block registersData register X’1F0’ UNC Idnf Features register X’1F1’ SET Multiple ModeSector Count register X’1F2’ Sector Number register X’1F3’ Cylinder Low register X’1F4’Cylinder High register X’1F5’ DEV HS3 HS2 HS1 HS0 Device/Head register X’1F6’Status register X’1F7’ BSY Interface Command register X’1F7’ Control block registersAlternate Status register X’3F6’ Command code and parameters Host CommandsDevice Control register X’3F6’ HOB Srst Command code and parameters 1 Command NameParameter Used EXT Flush Cache EXT Command code and parameters 2 Host Commands Command descriptions Host Commands Recalibrate X’10’ to X’1F’ MSB Read Sectors X’20’ or X’21’ End head No. / LBA MSB Read Long X’22’ or X’23’ Write Sectors X’30’ or X’31’ 1F7 HST Status information 1F6 HDH Write Long X’32’ or X’33’ Write Verify X’3C’ Read Verify Sectors X’40’ or X’41’ Seek X’70’ to X’7F’ Diagnostic code Execute Device Diagnostic X’90’ Host Commands Initialize Device Parameters X’91’ Download Micro Code X’92’ Operation of Download Micro Code 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 ’FF’ Check Power Mode X’98’ or X’E5’ Sleep X’99’ or X’E6’ Smart X’B0 Features Register values subcommands and functions 1 Smart Enable Operations Features Register values subcommands and functions 2Smart Disable Operations Smart Read LOG Features Register values subcommands and functions 3 Smart ENABLE/DISABLE Auto OFF-LINE’DA’ Smart Return Status Interface Format of device attribute value data 1FFFormat of insurance failure threshold value data Attribute ID Data format version number Current attribute value Status FlagAttribute value for the worst case so far Raw attribute value 10 Off-line data collection status Self-test execution status11 Self-test execution status 12 Off-line data collection capability Off-line data collection capabilityFailure prediction capability flag 13 Failure prediction capability flag 14 Error logging capability Error logging capabilityCheck sum Insurance failure threshold Smart error logging 16 Data format of Smart Summary Error Log Error data structure Command data structureTotal number of drive errors 17 Data format of Smart Comprehensive Error Log 18 Smart self-test log data format Smart Self-Test1FC Self-test number Test Span 19 Selective self-test log data structureCurrent LBA under test Current Span under test Feature Flags 20 Selective self-test feature flagsSelective Self-test pending time min Device Configuration Restore Device Configuration XB1Device Configuration Freeze Device Configuration Identify Device Configuration Freeze Lock FR = C1h Device Configuration Restore FR = C0hDevice Configuration Identify FR = C2h Device Configuration SET FR = C3h Host Commands 21 Device Configuration Identify data structure Read Multiple X’C4’ Execution example of Read Multiple command 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’ ’3FFF’ 22 Information to be read by Identify Device command 1 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 Diagnosis Word Bit Reserved Security level High, 1 Maximum 23 Features register values and settable modes SET Features X’EF’’AA’ ’BB’ 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 1F7 hCM 1F6 hDH When the master password is selected When the user password is selectedSecurity UNLOCKX’F2’ Host Commands Security Erase Prepare X’F3’ Security Erase Unit X’F4’ Security Freeze Lock X’F5’ At command issuance I-O register contents 1F7 hCM 1F6 hDH 26 Contents of security password Host Commands Read Native MAX Address X’F8’ SET MAX Address SET MAX X’F9’ SET MAX SET Password FR = 01h SET MAX Lock FR = 02h SET MAX Unlock FR = 03h SET MAX Freeze Lock FR = 04h Interface Read Sectors EXT X’24’ Option customizing Description Read DMA EXT X’25’ Option customizing Description Error reporting conditions HOB=0HOB=1 Read Multiple EXT X’29’ Option customizing Description Read LOG EXT X2F Optional command Customize Description Interface 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 LOG EXT X’3F’ Optional command Customize Description Host Commands Read Verify Sectors EXT X’42 Option customizing Description Flush Cache EXT X’EA’ Option customizing Description 27 Command code and parameters 1 Error posting 27 Command code and parameters 2 Command Protocol PIO Data transferring commands from device to hostExecute Device Diagnostic Initialize Device Parameters Read Sectors Command protocol Protocol for command abort PIO Data transferring commands from host to device Write Sectors command protocol Commands without data transfer DMA data transfer commands Other commandsRead Multiple EXT Write Multiple EXT Sleep Read DMA EXT Write DMA EXT Indentify Device DMA Normal DMA data transfer Overview Ultra DMA Feature Set Phases of operation Ultra DMA data in commandsInitiating an Ultra DMA data in burst Data in transfer Pausing an Ultra DMA data in burst Terminating an Ultra DMA data in burst Interface Ultra DMA Feature Set Initiating an Ultra DMA data out burst Ultra DMA data out commands Data out transfer Pausing an Ultra DMA data out burst Terminating an Ultra DMA data out burst Ultra DMA Feature Set Ultra DMA CRC rules 28 Recommended series termination for Ultra DMA Series termination required for Ultra DMADIOR-HDMARDY-HSTROBE DIOW-STOP Timing PIO data transferPIO data transfer timing Multiword data transfer 10 Multiword DMA data transfer timing mode 11 Initiating an Ultra DMA data in burst Ultra DMA data transfer Strobe Name Mode Comment MIN MAX 29 Ultra DMA data burst timing requirements 2 30 Ultra DMA sender and recipient timing requirements Mode Name Comment Dstrobe at device Sustained Ultra DMA data in burstDD150 at device Dstrobe at host DD150 at host Dmarq Host pausing an Ultra DMA data in burstDmack Stop Device terminating an Ultra DMA data in burst Host terminating an Ultra DMA data in burst HostDA0, DA1, DA2 CS0, CS1 16 Initiating an Ultra DMA data out burst Sustained Ultra DMA data out burst Hstrobe at host DD150 at hostHstrobe at device DD150 at device Device pausing an Ultra DMA data out burst Device DMACK- host Stop host DDMARDY- deviceHstrobe host DD150 Host 19 Host terminating an Ultra DMA data out burst Host terminating an Ultra DMA data out burst Device terminating an Ultra DMA data out burst Dmarq device DMACK- hostDD150 Host Power-on and reset Master and slave devices are present 2-drives configurationOnly master device is present This page is intentionally left blank Operations Response to power-on Device Response to the Reset Response to power-on Response to hardware reset Response to hardware reset Response to software reset Response to software reset Response to diagnostic command Response to diagnostic command Power save mode Power SaveActive mode Active idle mode Sleep mode Standby mode Power commands Defect ProcessingSpare area Alternating processing for defective sectors Sector slip processingTrack slip processing Automatic alternating processing Automatic alternating processing Data buffer structure Read-ahead Cache8MB buffer 8,388,608 bytes Read Sectors EXT Read Multiple EXT Read DMA EXT Caching operation Commands that are targets of cachingRead Multiple EXT Read Dmaext Data that is a target of caching Operations Miss-hit Using the read segment buffer Sequential Hit Full hit Partial hit Write Cache Command that are targets of cachingCache operation Invalidation of cached data Reset response Status report in the event of an errorCashing function when power supply is turned on Enabling and disabling Write Cache This page is intentionally left blank Glossary Rotational delay Power save modePIO Programmed input-output Positioning VCM Status This page is intentionally left blank Acronyms and Abbreviations This page is intentionally left blank AAM Index Index Information to be read by Identify Read Native MAX Address Read Sectors Command Surface temperature measurement This page is intentionally left blank Japan Comment Form This page is intentionally left blank C141-E202-01EN This page is intentionally left blank