Maxtor 52049H3, 51536H2, 53073H4, 546106 specifications CacheManagement

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PRODUCT DESCRIPTION

Defect Management Zone (DMZ)

Each drive model has a fixed number of spare sectors per drive, all of which are located at the end of the drive. Upon detection of a bad sector that has been reassigned, the next sequential sector is used.

For example, if sector 3 is flagged, data that would have been stored there is “pushed down” and recorded in sector 4. Sector 4 then effectively becomes sector 3, as sequential sectors are “pushed down” across the entire drive. The first spare sector makes up for the loss of sector 3, and so maintains the sequential order of data. This push down method assures maximum performance.

On-the-Fly Hardware Error Correction Code (ECC)

16 symbols, single burst, guaranteed.

Software ECC Correction

24 symbols, single burst, guaranteed.

Automatic Park and Lock Operation

Immediately following power down, dynamic braking of the spinning disks delays momentarily allowing the read/write heads to move to an inner mechanical stop. A small fixed magnet holds the rotary actuator in place as the disk spins down. The rotary actuator is released only when power is again applied.

CacheManagement

Buffer Segmentation

The data buffer is organized into two segments: the data buffer and the micro controller scratch pad. The data buffer is dynamically allocated for read and write data depending on the commands received. A variable number of read and write buffers may exist at the same time.

Read-Ahead Mode

Normally, this mode is active. Following a read request, disk read-ahead begins on the first sector and continues sequentially until the allocated buffer is full. If a read request is received during the read-ahead operation, the buffer is examined to determine if the request is in the cache. If a cache hit occurs, read- ahead mode continues without interruption and the host transfer begins immediately.

Automatic Write Reallocation (AWR)

This feature is part of the write cache and reduces the risk of data loss during deferred write operations. If a disk error occurs during the disk write process, the disk task stops and the suspect sector is reallocated to a pool of alternate sectors located at the end of the drive. Following reallocation, the disk write task continues until it is complete.

Write Cache Stacking

Normally, this mode is active. Write cache mode accepts the host write data into the buffer until the buffer is full or the host transfer is complete. A command complete interrupt is generated at the end of the transfer.

A disk write task begins to store the host data to disk. Host write commands continue to be accepted and data transferred to the buffer until either the write command stack is full or the data buffer is full. The drive may reorder write commands to optimize drive throughput.

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Contents Corporate Headquarters REV EC N O SEC Tion Desc Ription ATE U T I O N Before You BeginContents Handling and Installation Product SpecificationsAT Interface Description Interface CommandsHost Software Interface Glossary Service and SupportFigures MaxtorCorporation IntroductionManualOrganization AbbreviationsConventions Product Description KeyFeaturesFunctional / Interface Product FeaturesModel S SP T MAX LB a Apac IT Y CacheManagement MajorHDAComponents Jumper Location / Configuration SubsystemConfigurationCylinderLimitationJumperDescription DriveConfiguration ProductSpecificationsPerformanceSpecifications ModelsandCapacitiesAram E TE R Stan D ARD ME T RIC PhysicalDimensionsmaximumPowerModeDefinitions PowerRequirementsEPA Energy Star Compliance EnvironmentalLimitsShock and Vibration ReliabilitySpecificationsParam E TE R OP ER AT ING ON- OPE R AT ING EMC/EMI SafetyRegulatoryComplianceHardDriveHandlingPrecautions HandlingandInstallationElectro-StaticDischargeESD Multi-pack Shipping Container UnpackingandInspectionRepacking PhysicalInstallationHook up Before You BeginStart up Set upATInterfaceDescription InterfaceConnectorPinDescriptionSummary PIN IGN ALPin Description Table PIN Name Signal Name Signal Desc RiptionPIO Timing IM in G Paramet ERS ModeDMATiming Imin G Paramet ERS ModeMode 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 HostSoftwareInterfacePOR T EAD WR ITE Conten TS LBA Bits CommandRegister M M a N D N a M E M M a N D code PA R a M E T E R S U S E D SummaryControl Diagnostic Registers Reset and Interrupt Handling InterfaceCommands ReadCommands Read DMA WriteCommands Write Multiple VAL UE DES C RIP Tion ModeSet/CheckCommandsLE VE L VAL UE Omman D Timer VAL UE TIME-OUT Period PowerModeCommandsSleep Mode Or D ENT Desc Ription InitializationCommandsOr D 15- 10, as c urrently defined Initialize Drive Parameters ER ROR Code Desc Ription Seek,FormatandDiagnosticCommandsKey Register A.R.T. CommandSetServicePolicy ServiceandSupportNoQuibbleService SupportFrom Dial Glossary AccesstimeCorrectableerror Fetch Landingzoneorlzone Physicalsector Softerror