Maxtor 6800 manual Cylinder Zero

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GLOSSARY

CYLINDER

Onseveraldisksurfacessharingacommonrotationalaxis,theaggregateoftracksata givenradialposition.Asetofdisktracksthataresimultaneouslyunderthesetofread/ writeheads.Thisthree-dimensionalstoragevolumecanbeaccessedafterasingleseek.

CYLINDER ZERO

Theoutermostcylinderinadrivethatcanbeusedfordatastorage.

D

DATA

Anorderedcollectionofinformation.Inaspecificcase,itistheinformationprocessed byacomputer.

DATA SEPARATOR

Anelectroniccircuitwhichdecodesplaybackdataandproducesseparateclockanddata bits.Sometimesincorrectlyusedtodenotedatasynchronizer.

DATA SYNCHRONIZER

Anelectroniccircuitproducingaclocksignalthatissynchronouswiththeincoming datastream.Thisclocksignalisthenusedtodecodetherecordingcodebeingusedinto userdata.

DATA TRANSFER RATE

Inadiskortapedrive,therateatwhichdataistransferredtoorfromthestorage media.Itisusuallygiveninthousandsofbitspersecond(Kbit/second)ormillionsof bitspersecond(Mbit/second).

DEDICATED LANDING ZONE

Adesignatedradialzoneonthediskwherecontactstartingandstoppingoccurby design.

DEDICATED SERVO

Aservoschemeinwhichaprerecordedpatternonanotherwiseunuseddisksurface providespositioninformationtotheservocircuitrybymeansofaheadreadingthat surface.

DEFECT

Amagneticimperfectioninarecordingsurface.

DEFECT MANAGEMENT

Ageneralmethodologyofavoidingdataerrorsonarecordingsurfacebyavoidingthe useofknownbadareasofmedia.Usuallydefectivesectorsortracksareretiredanddata arewritteninalternatelocations.Severalalgorithmsarepossiblesuchas“sector slipping,”or“sparesectorpertrack.”

DEFECT MAP

Alistofdefectsthatfallwithinapass/failcriteriaofauser.Thislistisusuallyusedbyan operatingsystemoradiskdrivecontrollerfordefectmanagement.

DEFECT SKIPPING

Adefectmanagementschemeforavoidingsurfacedefects.Ithasdatawrittenbeforeand afterthedefect,insteadofusingalternatetracksorsectorstoavoiduseofthedefective area.

DENSITY

Generally,recordingdensity.Seeareal,bit,andstoragedensity.

DC ERASE

ThemethodoferasingatrackusingaDCwrite/erasecurrentthrougheitheraRead/ WriteorErasehead.

DIGITAL

Anysystemthatprocessesdigitalbinarysignals(havingonlyvaluesofa1or0;usually inbitsandbytes)ratherthananalogsignals(signalsthatcanhavemanyvalues)

DIGITAL MAGNETIC RECORDING

Seemagneticrecording.

DIRECT ACCESS

Accessdirectlytomemorylocation.(Seerandomaccess).

DIRECT MEMORY ACCESS

Ameanofdatatransferbetweenthedeviceandhostmemorywithoutprocessor intervention.

DIRECTORY

Alistingoffilesmaintainedbythediskoperationsystem(DOS)oradatabase managementsystemtoenableausertoquicklyaccessdatafiles.

DISK

Aflat,circularpieceofmetal(usuallyaluminum)orplastic(usuallymylar)witha magneticcoatinguponwhichinformationcanberecorded.(See,forexample,floppy diskorWinchesterdisk)

DISK DRIVE OR DISK MEMORY DEVICE

Thetotalelectromechanicalstoragedevicecontainingdisksandread/writeheads,head positioningmechanism,drivemotor,andelectronics.

DISK PACK

Anumberofmetaldiskspackagedinacanisterforremovalfromthediskdrive (predecessorofWinchestertechnology).

DISK OPERATING SYSTEM (DOS) Themastercomputersystemprogramthatschedulestasks,allocatesthecomputersystem resources,controlsaccessestomassstoragedevices,managesfiles,andsoforth.Typical diskoperatingsystemsincludeCP/M,MS-DOS,andUNIX.

DISK STORAGE

Auxiliarymemorysystemcontainingdiskdrives.

DISK TRANSFER RATE

Theratethatdigitaldataistransferredfromonepointtoanother.Expressedineither bits/secondorbytes/second.

DOUBLE FREQUENCY ENCODING

AnothernameforFMencoding.Thisisbecauseallpossibledatacombinationswill resultinonlytwopossibletemporaldisplacementsofadjacentdatabits,specifically “1F”and2F.”

E

EARLY WINDOW

Adatawindowthathasbeenintentionallyshiftedintimeinanearlydirection.

EMBEDDED SERVO

Aservotechniqueusedfortrackfollowing.Positioninformationisprerecorded betweendataareasinatracksothatadatahead,andproperadditionalcircuitry,can determinethedataheadlocationwithrespecttothecenterpositionofthetrack(or cylinder)inquestion.

ERASE

Aprocessbywhichasignalrecordedonamediumisremovedandthemediummade readyforrerecording.

ERROR CORRECTION CODE (ECC)

Amathematicalalgorithmthatcandetectandcorrecterrorsinadatafield.Thisis accomplishedwiththeaidofCheckBitsaddedtotherawdata.

ERROR FREE

Arecordingsurfacethathasnodefects.

ERROR RATE

Thenumberoferrors(typemustbespecified)thatoccurinaspecifiednumberofbits read.

ERROR RECOVERY PROCEDURE

Theprocessthatoccursinresponsetoadataerror.InadrivewithoutECC,this wouldincludere-calibrationandre-seekingtothespecifiedtrackandrereadingthe specifieddata.

EXTRA PULSE

Termusedinsurfacecertification.Itiswhenafluxfielddiscontinuityremainsafterthe recordingsurfaceiserased,therebyproducinganelectricaloutputofareadhead passingovertheareawiththediscontinuity.Anextrapulseoccurswhentheelectrical outputislargerthanaspecifiedthreshold.

F

FEEDBACK

Inaclosed-loopsystem,theoutputsignal(fromtheservohead)isusedtomodifythe inputsignal(tothepositioner).

FETCH

Areadoperationanditsrelateddatatransferoperations.

GL – 2

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Contents HA RD Drive Produc T MA Nual DiamondMax U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionGlossary Interface CommandsService and Support Figures Maxtor Corporation IntroductionManual Organization AbbreviationsConventions Signal ConventionsKey Words NumberingProduct Description DiamondMax 6800 Key FeaturesFunctional / Interface Product FeaturesLogical Block Addressing On-the-Fly Hardware Error Correction Code ECCDefect Management Zone DMZ Software ECC CorrectionCache Management Read-Ahead ModeBuffer Segmentation Automatic Write Reallocation AWRMajor HDA Components Jumper Location/Configuration Subsystem ConfigurationCylinder Limitation Dual Drive SupportDrive Configuration Product SpecificationsPerformance Specifications Models and CapacitiesParameter Standard Metric Physical DimensionsPower Mode Definitions Power RequirementsEPA Energy Star Compliance Environmental LimitsShock and Vibration Reliability SpecificationsCanadian Emissions Statement Safety Regulatory ComplianceRadiated Electromagnetic Field Emissions EMC Compliance Hard Drive Handling Precautions Handling and InstallationPre-formatted Drive Important NoticeMulti-pack Shipping Container Unpacking and InspectionRepacking Physical InstallationRecommended Mounting Configuration Tools for Installation Handling PrecautionsSystem Requirements Drive Identification InformationHard Drive Identification General RequirementsInstalling 5.25-inch Mounting Brackets and Rails Systems Using Cable SelectInstalling in a Device Bay Mounting Drive in SystemAttaching System Cables Attaching Interface and Power CablesBios Cmos Parameters System SetupSetting the Bios Cmos Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorAT Interface Description Pin Description Table PIN Name Signal Name Signal DescriptionPIO Timing Timing Parameters ModeDMA Timing Ultra DMA Timing Mode MIN MAXSustained Ultra DMA Data In Burst Device Terminating an Ultra DMA Data In Burst Initiating an Ultra DMA Data Out Burst Device Pausing an Ultra DMA Data Out Burst Device Terminating an Ultra DMA Data Out Burst Features Register Error RegisterHost Software Interface Task File RegistersSector Number Register Sector Count RegisterCylinder Number Registers Device/Head RegisterCommand Register Summary Command Name Command Code Parameters Used SDHAlternate Status Register Control Diagnostic RegistersDevice Control Register Digital Input RegisterInterrupt Handling Reset and Interrupt HandlingReset Handling Set Feature Commands Interface CommandsRead Verify Sectors Read CommandsRead Sectors Read Multiple Read DMASet Multiple Mode Write CommandsWrite Sectors Write Verify SectorsWrite DMA Write MultipleSet Features Mode Set Feature CommandsPower Mode Commands Sleep Mode Identify Drive Initialization Commands15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Format Track Seek, Format and Diagnostic CommandsExecute Drive Diagnostic Execute S.M.A.R.T A.R.T. Command SetService Policy Service and SupportNo Quibble Service SupportInternet MaxFax ServiceCustomer Service Glossary Access TimeCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media
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