Logical Block Addressing

GLOSSARY

LOGICAL ADDRESS

Astoragelocationaddressthatmaynotrelatedirectlytoaphysicallocation.Usually usedtorequestinformationfromacontroller,whichperformsalogicaltophysical addressconversion,andinturn,retrievesthedatafromaphysicallocationinthemass storageperipheral.

Definestheaddressingofthedevicebythelinearmappingofsectors.

LOGICAL SECTOR

ThelowestunitofspacethatDOScanaccessthroughadevicedriver;oneormore physicalsectors.

LOW FREQUENCY

Thelowestrecordingfrequencyusedinaparticularmagneticrecordingdevice.With FMorMFMchannelcodes,thisfrequencyisalsocalled“IF.”

MAIN MEMORY Random-accessmemory(RAM)usedbythecentralprocessingunit(CPU)forstoring programinstructionsanddatacurrentlybeingprocessedbythoseinstructions.(Seealso randomaccessmemory.)

MASS STORAGE

Auxiliarymemoryusedinconjunctionswithmainmemory;generallyhavingalarge, on-linestoragecapacity.

MEGABYTE (MB)

Aunitofmeasureapproximatelyonemillionbytes(actually1,048,576bytes)or106.

MEMORY

Anydeviceorstoragesystemcapableofstoringandretrievinginformation.(Seealso storagedefinitions.)

MICROCOMPUTER

Acomputerwhosecentralprocessingunitisamicroprocessor.Itisusually,butnot necessarily,desktopsize.

MICROPROCESSOR

Acentralprocessingunit(CPU)manufacturedasachiporasmallnumberofchips.

MISSING PULSE

Atermusedinsurfacecertification.Itiswhenaprerecordedsignalisreducedin amplitudebyacertainspecifiedpercentage.

MODIFIED FREQUENCY MODULATION (MFM)

Amethodofencodingdigitaldatasignalsforrecordingonmagneticmedia.Alsocalled “threefrequencyrecording.”Recordingcodethatonlyusessynchronizingclockpulse ifdatabitsarenotpresent.Doublesthelinealbitdensitywithoutincreasingthelineal fluxreversaldensity,comparedtoFrequencyModulation.

MODIFIED MODIFIED FREQUENCY MODULATION (MMFM)

ArecordingcodesimilartoMFMthathasalongerrunlengthlimiteddistance.

MODULATION

1.Readbackvoltagefluctuationusuallyrelatedtotherotationalperiodofadisk.2.A recordingcode,suchasFM,MFM,orRLL,totranslatebetweenfluxreversalsandbits orbytes.

NON-RETURN TO ZERO

Aformofdataencodingthatisnotself-clocking,inotherwords,itneedstobe providedwithanexternalbitcellclocksignal.Generallyusedinhigher-performance diskdrives.

OFF-LINE processingorperipheraloperationsperformedwhiledisconnectedfromthesystem CPUviathesystembus.

ON-LINE processingorperipheraloperationsperformedwhiledisconnectedfromthesystem CPUviathesystembus.

OPEN LOOP SERVO

Aheadpositioningsystemthatdoesnotusepositionalinformationtoverifyandcorrect theradiallocationoftheheadrelativetothetrack.Thisisusuallyachievedbyuseofa steppermotorwhichhaspredeterminedstoppingpointthatcorrespondstotrack locations.

OPERATING SYSTEM

Asoftwareprogramthatorganizestheactionsofthepartsofthecomputerandits peripheraldevices.(Seediskoperatingsystem.)

OUTSIDE DIAMETER

Thelargestradiusrecordingtrackonadisk.

OVERWRITE

Atestthatmeasurestheresidual1Frecordedfrequencyonatrackafterbeing overwrittenbya2Fsignal.Variationsofthetestexist.

PARALLELISM

1.Theconditionoftwoplanesorlinesbeingparallel.Importantindiskdrivesbecause alackofitinmechanicalassembliescanresultinpositioninginaccuracy.More precisely:planes-coplanar;lines-colinear.2.Isthelocalvariationindiskthickness measuredindependentlyofthicknessitself.3.Theabilityofamultiprocessorcomputer toallocatemorethanoneprocessor(CPU)toacomputingproblem,whereeachCPU worksonaseparateproblemorseparatesegmentofthatproblem.Alsoreferredtoas parallelprocessing.

PARITY

Asimplemethodofdataerrordetectionsthatalwaysmakesnumberseitheroddor even,usinganextrabitinwhichthetotalnumberofbinary1s(or0s)inabyteis alwaysoddoralwayseven;thus,inanoddparityscheme,everybytehaseightbitsof dataandoneparitybit.Ifusingoddparityandthenumberof1bitscomprisingthe byteofdataisnotodd,theninthorparitybitissetto1tocreatetheoddparity.Inthis way,abyteofdatacanbecheckedforaccuratetransmissionbysimplycountingthe bitsforanoddparityindication.Ifthecountisevereven,anerrorisindicated.

PARTITION

Alogicalsectionofadiskdrive,eachofwhichbecomesalogicaldevicewithadrive letter.

PEAK SHIFT

Theshiftingintimeofthezero-slopeportionofareadbackvoltagefromthevalues containedinthewritecurrentwaveform.Sometimesincorrectlyusedtodescribebit jitter.

PERIPHERAL EQUIPMENT

Auxiliarymemory,displays,printers,andotherequipmentusuallyattachedtoa computersystem’sCPUbycontrollersandcables.(Theyareoftenpackagedtogetherin adesktopcomputer.)

PHASE LOCKED LOOP (PLL)

Acircuitwhoseoutputlocksontoandtracksthefrequencyofaninputsignal. Sometimesincorrectlycalledadataseparator.

PHASE MARGIN Measureindegreesoftheamountofdifferencebetweenexcursionsfromthewindow centerwherefluxreversalscanoccurandtheedgeofthedatawindow.Similarto windowmargin.

PHYSICAL SECTOR

Thesmallestgroupingofdataontheharddisk;always512bytes.

PIO

ProgrammableInputOutput.Ameansofaccessingdeviceregisters.Alsodescribesone formofdatatransfers.PIOdatatransfersareperformedbythehostprocessorusing PIOregisteraccessestothedataregister.

PLATED THIN FILM MEDIA

Magneticdiskmemorymediahavingitssurfaceplatedwithathincoatingofametallic alloyinsteadofbeingcoatedwithoxide.

PROCESSING

Theprocessofthecomputerhandling,manipulatingandmodifyingdatasuchas arithmeticcalculation,filelookupandupdating,andwordpressing.

PULSE CROWDING

Modificationofplaybackamplitudeduetosuper-positioningofadjacentfluxreversal fieldsbeingsensedbytheread/writegap.

PULSE DETECT

Adigitalpulsetraininwhicheachleadingedgeoreachedgecorrespondstoa magnetictransitionreadfromthedisk.Iftransitionqualificationcircuitryexistsinthe drive,thissignalistheoutputofsame.Alsoknownastransitiondetect.

GL – 4

91024U3, 92049U6, 90683U2, 91707U5, 92732U8 specifications

The Maxtor series of hard drives, specifically the models 91366U4, 92732U8, 91707U5, 90683U2, and 92049U6, exemplify the evolution of storage technology during the late 1990s and early 2000s, pivotal in shaping contemporary data storage solutions. These hard drives are recognized for their reliability, performance, and impressive capacities for their time.

The Maxtor 91366U4 features a storage capacity of 13.6 GB, delivering a spindle speed of 5,400 RPM. Its UATA interface allows for a fast data transfer rate, which was notable in its category. The model incorporates Advanced Power Management, contributing to lower power consumption and reduced heat generation, making it an appealing choice for system builders looking to enhance system longevity.

Moving on to the Maxtor 92732U8, this model increased capacity to 27.3 GB, aligning with the growing demand for more storage from users and businesses alike. This drive maintained a 5,400 RPM spindle speed while improving the access times, which aided in speeding up file retrieval processes. Noteworthy is its Plug and Play capability, which simplified installation and compatibility across various systems.

The Maxtor 91707U5 brought forward advancements in data integrity with the inclusion of features such as error correction codes. With a storage size of 17.3 GB and similar operational speeds, this model catered to users seeking reliable data management. Its robust build aimed to protect against accidents and environmental factors, ensuring data was safe while providing consistent performance.

The Maxtor 90683U2, with its 68.3 GB capacity, is particularly recognized for its reliability in desktop applications. The drive integrates a combination of Unidirectional Technology, driving advancements in read/write capabilities, and extensive shock protection, making it an ideal candidate for users with intensive data processing requirements.

Lastly, the Maxtor 92049U6 is known for its balanced blend of performance and functionality. Holding a capacity of 49.1 GB and retaining the sophisticated features of its predecessors, this model enabled faster data access and storage capabilities that met the needs of both home and professional users.

Together, these Maxtor hard drives embody the technological strides in the evolution of data storage—offering capacities and performances that set a standard in the industry and laid the groundwork for future storage solutions. The combination of innovative technologies and practical features made these drives highly sought after during their respective periods, and their legacy continues to influence modern data storage products.

Maxtor 92049U6, 91024U3, 90683U2, 91366U4, 91707U5, 92732U8 manual Logical Block Addressing

Models: 91024U3 92049U6 90683U2 91707U5 92732U8 91366U4

LOGICAL ADDRESS