Maxtor 5120 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 92048U8, 91792U7, 91536U6, 91280U5, 91024U4 and 90750U3 DiamondMax PlusRevisions Manual No U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionInterface Commands Service and SupportGlossary Figures Maxtor Corporation IntroductionManual Organization AbbreviationsConventions Signal ConventionsKey Words NumberingProduct Description DiamondMax Plus 5120 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 Requirements AverageEPA Energy Star Compliance Environmental LimitsShock and Vibration Reliability SpecificationsSafety Regulatory Compliance Radiated Electromagnetic Field Emissions EMC ComplianceCanadian Emissions Statement Hard Drive Handling Precautions Handling and InstallationPre-formatted Drive Important NoticeMulti-pack Shipping Container Unpacking and InspectionPhysical Installation Recommended Mounting ConfigurationRepacking 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 CablesSystem Setup Setting the Bios CmosBios Cmos Parameters Hard Drive Preparation System Hangs During Boot Interface Connector AT Interface DescriptionPin Description Summary 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 RegisterReset and Interrupt Handling Reset HandlingInterrupt Handling Set Feature Commands Interface CommandsRead Commands Read SectorsRead Verify 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 Seek, Format and Diagnostic Commands Execute Drive DiagnosticFormat Track Execute S.M.A.R.T A.R.T. Command SetService Policy Service and SupportNo Quibble Service SupportMaxFax Service Customer ServiceInternet Glossary Access TimeCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media
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