Maxtor VL 17 manual Gigabyte GB

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.