Maxtor 6800 manual Read Gate Signal

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R

RANDOM ACCESS MEMORY (RAM)

Memorydesignedsothatanystoragelocationcanbeaccessedrandomly,directlyand individually.Thisiscontrastedtosequentialaccessdevicessuchastapedrives.

READ

Toaccessastoragelocationandobtainpreviouslyrecordeddata.Tosensethepresence offluxreversalsonmagneticmedia.Usuallyimplementedsuchthatadynamicflux amplitudewillcauseaproportionalelectricaloutputfromthetransducer.

READ GATE SIGNAL

Adigitalinputsignalwhichcausesthedrivecircuitrytorecoverdata.

READ ONLY MEMORY (ROM)

Aformofmemorywhichcannotbechangedinformaloperationalmodes.Many differenttypesareavailable.RAMisusedforpermanentinformationstorage. ComputercontrolprogramsareoftenstoredinROMapplications.

READ/WRITE HEAD

Therecordingelementwhichwritesdatatothemagneticmediaandreadsrecorded datafromthemedia.

RE-CALIBRATE

Theactionofmovingtheheadofadiskdrivetocylinderzero.

RECOVERABLE ERROR

Areaderror,transientorotherwise,fallingwithinthecapabilityofanECC mechanismtocorrect,orabletoovercomebyrereadingthedatainquestion.

ROTATIONAL LATENCY

Theamountofdelayinobtaininginformationfromadiskdriveattributabletothe rotationofthedisk.

RUN-LENGTH LIMITED

Anencodingprocessthatrepositionsdatabitsandlimitsthelengthofzerobitsinorder tocompressinformationbeingstoredondisks.

RUN-LENGTH LIMITED ENCODING

Arecordingcode.Sometimesmeanttodenote“2.7RLL”whichcansignify1.5times thebitsasMFM,giventhesamenumberoffluxreversalsinagivenlinealdistance.

S

SECTOR

Alogicalsegmentofinformationonaparticulartrack.Thesmallestaddressableunitof storageonadisk.Tracksaremadeofsectors.

SECTOR PULSE SIGNAL

Adigitalsignalpulsepresentinhardsectoreddriveswhichindicatesthebeginningofa sector.Embeddedservopatternorotherprerecordedinformationmaybepresenton thediskwhensectorisactive.

SEEK

Arandomaccessoperationbythediskdrive.Theactofmovingasetofread/write headssothatoneofthemisoverthedesiredcylinder.Theactuatororpositionermoves theheadstothecylindercontainingthedesiredtrackandsector.

SEEK COMPLETE SIGNAL

Adigitalsignallevelwhichindicatesthatthepositionerisnotmovingandislocated overacylinderoroffsetposition.

SEEK TIME

Theamountoftimebetweenwhenasteppulseorseekcommandisissueduntilthe headsettlesontothedesiredcylinder.Sometimesismeasuredwithoutsettlingtimes.

SEQUENTIAL ACCESS

Thewritingorreadingofdatainasequentialordersuchasreadingdatablocksstored oneaftertheotheronmagnetictape.Thisiscontrastedtorandomaccessof information.

SERVO BURST

Amomentaryservopatternusedinembeddedservocontrolsystemsusuallypositioned betweensectorsorattheendofatrack.

SERVO CONTROL

Atechniquebywhichthespeedorpositionofamovingdeviceisforcedinto conformitywithadesiredorstandardspeedorposition.

GLOSSARY

SERVO HEAD

Amagneticheaddesignedspecificallyforaccuratelyreadingservodata.

SERVO PATTERN

Areadbacksignalthatindicatesthepositionofaheadrelativetoatrack.

SERVO SURFACE

Arecordingsurfaceinamulti-surfacediskdrivethatonlycontainscontrolinformation whichprovidestiming,headposition,andtrack-followinginformationforthedata surfaces.

SERVO SYSTEM

Anautomaticsystemformaintainingtheread/writeheadontrack;canbeeither“open loop,”“quasi-closedloop,”or“closedloop.”

SERVO TRACK

Atrackonaservosurface.Theprerecordedreferencetrackonthededicatedservo surfaceofadiskdrive.Alldatatrackpositionsarecomparedtotheircorresponding servotrack todetermine“offtrack”/”ontrack”position.

SETTLING TIME

Thetimeittakesaheadtostopvibrating,withinspecifiedlimits,afteritreachesthe desiredcylinder.

SILICON Semiconductormaterialgenerallyusedtomanufacturemicroprocessorsandother integratedcircuitchips.

SMALL COMPUTER SYSTEM INTERFACE (SCSI)

Anintelligentinterfacethatincorporatescontrollerfunctionsdirectlyintothedrive.

S.M.A.R.T. CAPABILITY Self-MonitoringAnalysisandReportingTechnology.Predictionofdevice degradationand/orfaults.

SOFT ERROR

Adataerrorwhichcanbeovercomebyrereadingthedataorrepositioningthehead.

SOFT SECTORED

Atechniquewherethecontrollerdeterminesthebeginningofasectorbythereading offormatinformationfromthedisk.Thisiscontrastedtohardsectoringwherea digitalsignalindicatesthebeginningofasectoronatrack.

SOFTWARE

Applicationsprograms,operatingsystems,andotherprograms(asopposedto hardware).

SPINDLE

Therotatinghubstructuretowhichthedisksareattached.

SPINDLE MOTOR

Themotorthatrotatesthespindleandthereforethedisks.

SPUTTERED MEDIA

Magneticdiskortapethathasthemagneticlayerdepositedbysputteringmeans.

STEPPER MOTOR

Amotorthathasknowndetentpositionswheretherotorwillstopwiththeproper controlinsomecases.Thedigitallycontrolledmotormovestheheadpositionerfrom tracktotrackinsmall,step-likemotions.

STORAGE CAPACITY

Theamountofdatathatcanbestoredinamemorylocation,usuallyspecifiedin kilobytesformainmemoryandfloppydrivesandmegabytesformassstoragedevices.

STORAGE DENSITY

Usuallyreferstorecordingdensity(BPI,TPI,oracombinationofthetwo.)

STORAGE LOCATION

Amemorylocation,identifiedbyanaddresswhereinformationmaybereador written.

STROBE OFFSET SIGNAL

AgroupofdigitalinputsignallevelswhichcausethereadPLLand/ordatadecoderto shiftthedecodingwindowsbyfractionalamounts.Oftenearly/latearemodifiedwhen twosignalsareused.

GL – 5

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Contents HA RD Drive Produc T MA Nual DiamondMax Before You Begin U T I O NContents Product Specifications Handling and InstallationAT Interface Description Host Software InterfaceGlossary Interface CommandsService and Support Figures Introduction Maxtor CorporationManual Organization AbbreviationsSignal Conventions ConventionsKey Words NumberingDiamondMax 6800 Key Features Product DescriptionProduct Features Functional / InterfaceOn-the-Fly Hardware Error Correction Code ECC Logical Block AddressingDefect Management Zone DMZ Software ECC CorrectionRead-Ahead Mode Cache ManagementBuffer Segmentation Automatic Write Reallocation AWRMajor HDA Components Subsystem Configuration Jumper Location/ConfigurationCylinder Limitation Dual Drive SupportProduct Specifications Drive ConfigurationPerformance Specifications Models and CapacitiesPhysical Dimensions Parameter Standard MetricPower Requirements Power Mode DefinitionsEPA Energy Star Compliance Environmental LimitsReliability Specifications Shock and VibrationCanadian Emissions Statement Safety Regulatory ComplianceRadiated Electromagnetic Field Emissions EMC Compliance Handling and Installation Hard Drive Handling PrecautionsPre-formatted Drive Important NoticeUnpacking and Inspection Multi-pack Shipping ContainerRepacking Physical InstallationRecommended Mounting Configuration Handling Precautions Tools for InstallationSystem Requirements Drive Identification InformationGeneral Requirements Hard Drive IdentificationSystems Using Cable Select Installing 5.25-inch Mounting Brackets and RailsInstalling in a Device Bay Mounting Drive in SystemAttaching Interface and Power Cables Attaching System CablesBios Cmos Parameters System SetupSetting the Bios Cmos Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorAT Interface Description PIN Name Signal Name Signal Description Pin Description TableTiming Parameters Mode PIO TimingDMA Timing Mode MIN MAX 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 Error Register Features RegisterHost Software Interface Task File RegistersSector Count Register Sector Number RegisterCylinder Number Registers Device/Head RegisterCommand Register Command Name Command Code Parameters Used SDH SummaryControl Diagnostic Registers Alternate Status RegisterDevice Control Register Digital Input RegisterInterrupt Handling Reset and Interrupt HandlingReset Handling Interface Commands Set Feature CommandsRead Verify Sectors Read CommandsRead Sectors Read DMA Read MultipleWrite Commands Set Multiple ModeWrite Sectors Write Verify SectorsWrite Multiple Write DMASet Feature Commands Set Features ModePower Mode Commands Sleep Mode Initialization Commands Identify Drive15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Format Track Seek, Format and Diagnostic CommandsExecute Drive Diagnostic A.R.T. Command Set Execute S.M.A.R.TService and Support Service PolicyNo Quibble Service SupportInternet MaxFax ServiceCustomer Service Access Time GlossaryCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media
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