Maxtor 90750D3 File Allocation Table FAT, Flux Changes PER Inch, Formatted Capacity, Head

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FILE ALLOCATION TABLE (FAT)

Allocatesspaceonthediskforfiles,oneclusteratatime;locksoutunusableclusters; identifiesunused(free)area;andlistsafile’slocation.WithtwoFAT’spresent,the secondcopyensuresconsistencyandprotectsagainstlossofdataifoneofthesectorson thefirstFATisdamaged.

FLUX CHANGES PER INCH

Synonymouswithfrpi(fluxreversalsperinch).OnlyinMFMrecordingdoes1fci equal1bpi(bitperinch).Inrun-length-limitedencodingschemes,generally1fci equals1.5bpi.

FORMAT

Inadiskdrive,thearrangementofdataonastoragemedia.Astandard5.25-inchdisk formatconsistsof17,26,or36sectorspertrack,and512bytesofdatapersector,plus identification,errorcorrection,andotherbytesnecessaryforaccessingand synchronizingdata.

FORMATTED CAPACITY

Theactualcapacityavailabletostoredatainamassstoragedevice.Theformatted capacityisthegrosscapacity,lessthecapacitytakenupbytheoverheaddatausedin formattingthesectors.

FREQUENCY MODULATION

Arecordingcode.Afluxreversalatthebeginningofacelltimerepresentsclockbit;a “1”bitisafluxreversalatthecenterofthecelltime,anda“0”bitisanabsenceofa fluxreversal.

FREQUENCY RESPONSE

Ameasureofhoweffectivelyacircuitordevicetransmitsthedifferentfrequencies appliedtoit.Indiskandtapedrivesthisreferstotheread/writechannel.Indisk drives,itcanalsorefertothedynamicmechanicalcharacteristicsofapositioning system.

G

GIGABYTE (GB)

Onebillionbytes(onethousandmegabytes)or109.

H

HARD ERROR

Anerrorthatisnotabletobeovercomebyrepeatedreadingsandrepositioningmeans.

HARD SECTORED

Atechniquewhereadigitalsignalindicatesthebeginningofasectoronatrack.Thisis contrastedtosoftsectoring,wherethecontrollerdeterminesthebeginningofasector bythereadingofformatinformationfromthedisk.

HEAD

Theelectromagneticdevicethatwrite(records),reads(playsback),anderasesdataona magneticmedia.Itcontainsareadcore(s)and/orawritecore(s)and/orerasecore(s) whichis/areusedtoproduceorreceivemagneticflux.Sometimesthetermisall inclusivetomeanthecarriageassemblywhichincludesthesliderandflexure.

HEAD CRASH

Theinadvertenttouchingofadiskbyaheadflyingoverthedisk(maydestroya portionofthemediaand/orthehead).

HEAD DISK ASSEMBLY (HDA)

Themechanicalportionofarigid,fixeddiskdrive.Itusuallyincludesdisks,heads, spindlemotor,andactuator.

HEAD LOADING ZONE

Thenon-dataareaonthedisksetasideforthecontrolledtakeoffandlandingofthe Winchesterheadswhenthedriveisturnedonandoff.Dedicatedannulusoneachdisk surfaceinwhichheadsareloaded,unloaded,orflyingheightisestablished.Head-disk contactmayoccurinsomeinstances;nodataisrecordedinthisarea.

HEAD POSITIONER

Alsoknownasactuator,amechanismthatmovesthearmsthatcarryread/writeheads tothecylinderbeingaccessed.

I

INDEX

Similartoadirectory,butusedtoestablishaphysicaltologicalcrossreference.Usedto updatethephysicaldiskaddress(tracksandsectors)offilesandtoexpediteaccesses.

GLOSSARY

INSIDE DIAMETER

Thesmallestradialpositionusedfortherecordingandplaybackoffluxreversalsona magneticdisksurface.

INITIALIZATION

Applyinginputpatternsorinstructionstoadevicesothatalloperationalparametersare ataknownvalue.

INPUT

Dataenteringthecomputertobeprocessed;alsousercommands.

INPUT/OUTPUT (I/O)

Theprocessofenteringdataintoorremovingdatafromacomputersystemora peripheraldevice.

INTELLIGENT PERIPHERAL

Aperipheraldevicethatcontainsaprocessorormicroprocessortoenableittointerpret andexecutecommands.

INTERFACE

Thedatatransmitters,datareceivers,logic,andwiringthatlinkonepieceofcomputer equipmenttoanother,suchasadiskdrivetoacontrolleroracontrollertoasystem bus.

INTERFACE STANDARD

Theinterfacespecificationsagreedtobyvariousmanufacturerstopromoteindustry- wideinterchangeabilityofproductssuchasadiskdrive.Interfacestandardsgenerally reduceproductcosts,allowsbuyerstopurchasefrommorethanonesource,andallow fastermarketacceptanceofnewproducts.

INTERLEAVE

Anorderingofphysicalsectorstobeskippedbetweenlogicalsectorsonyourhard disk.

I/O PROCESSOR

Intelligentprocessororcontrollerthathandlestheinput/outputoperationsofa computer.

INTERRUPT

Asignal,usuallyfromasubsystemtoacentralprocessingunit,tosignifythatan operationhasbeencompletedorcannotbecompleted.

J

JUMPER

Asmallpieceofplasticthatslidesoverpairsofpinsthatprotrudefromthecircuitboard ontheharddrivetomakeanelectricalconnectionandactivateaspecificoption.

K

KILOBYTE (KB)

Aunitofmeasureofapproximately1,000bytes.(However,becausecomputer memoryispartitionedintosizesthatareapoweroftwo,akilobyteisreally1,024 bytes.)

L

LANDING ZONE OR LZONE

ThecylindernumbertowhereParkHeadsmovetheread/writeheads.

LATE BIT

Abitthatisinthelatehalfofthedatawindow.

LATE WINDOW

Adatawindowthathasbeenshiftedinalatedirectiontofacilitatedatarecovery.

LATENCY

Adelayencounteredinacomputerwhenwaitingforaspecificresponse.Inadisk drivethereisbothseeklatencyandrotationallatency.Thetimerequiredforthe addressedsectortoarriveundertheheadaftertheheadispositionedoverthecorrect track.Itisaresultofthedisk’srotationalspeedandmustbeconsideredindetermining thediskdrive’stotalaccesstime.

LOGIC

Electroniccircuitrythatswitchesonandoff(“1”and“0”)toperformfunctions.

GL – 3

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Contents HA RD Drive Produc T MA Nual DiamondMax Plus Revisions Manual No U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionService and Support Interface CommandsGlossary Figures Abbreviations IntroductionMaxtor Corporation Manual OrganizationNumbering Signal ConventionsConventions Key WordsProduct Description DiamondMax Plus 5120 Key FeaturesFunctional / Interface Product FeaturesSoftware ECC Correction On-the-Fly Hardware Error Correction Code ECCLogical Block Addressing Defect Management Zone DMZAutomatic Write Reallocation AWR Read-Ahead ModeCache Management Buffer SegmentationMajor HDA Components Dual Drive Support Subsystem ConfigurationJumper Location/Configuration Cylinder LimitationModels and Capacities Product SpecificationsDrive Configuration Performance SpecificationsParameter Standard Metric Physical DimensionsEnvironmental Limits Power RequirementsPower Mode Definitions EPA Energy Star ComplianceShock and Vibration Reliability SpecificationsRadiated Electromagnetic Field Emissions EMC Compliance Safety Regulatory ComplianceCanadian Emissions Statement Important Notice Handling and InstallationHard Drive Handling Precautions Pre-formatted DriveMulti-pack Shipping Container Unpacking and InspectionRecommended Mounting Configuration Physical InstallationRepacking Before You Begin General Requirements Mounting Drive in System Attaching Interface Power Cables System Setup Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorSignal AT Interface DescriptionPin Description Table PIN Name Signal Name Signal DescriptionPIO Timing Timing Parameters ModeDMA Timing Timing Parameters all times in nanoseconds Ultra DMA TimingSustained 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 Task File Registers Error RegisterFeatures Register Host Software InterfaceDevice/Head Register Sector Count RegisterSector Number Register Cylinder Number RegistersCommand Register Summary Command Name Command Code Parameters Used SDHDigital Input Register Control Diagnostic RegistersAlternate Status Register Device Control RegisterReset Handling Reset and Interrupt HandlingInterrupt Handling Set Feature Commands Interface CommandsRead Sectors Read CommandsRead Verify Sectors Read Multiple Read DMAWrite Verify Sectors Write CommandsSet Multiple Mode Write 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 Execute Drive Diagnostic Seek, Format and Diagnostic CommandsFormat Track Execute S.M.A.R.T A.R.T. Command SetSupport Service and SupportService Policy No Quibble ServiceCustomer Service MaxFax ServiceInternet Glossary Error Free Direct AccessDirect Memory Access Error Correction Code ECCFlux Changes PER Inch Hard ErrorHead Disk Assembly HDA File Allocation Table FATLogical Sector Phase Locked Loop PLLLogical Address Logical Block AddressingSector Pulse Signal Random Access Memory RAMRead Gate Signal Recoverable ErrorTHIN-FILM Media UN-CORRECTABLE ErrorUnrecoverable Error Write Gate Signal
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