Maxtor VL 17 manual Logical Block Addressing, Defect Management Zone DMZ

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PRODUCTDESCRIPTION

Logical Block Addressing

The Logical Block Address (LBA) mode can only be utilized in systems that support this form of translation. The cylinder, head and sector geometry of the drive, as presented to the host, differs from the actual physical geometry. The host AT computer may access a drive of set parameters: number of cylinders, heads and sectors per track, plus cylinder, head and sector addresses. However, the drive can’t use these host parameters directly because of zoned recording techniques. The drive translates the host parameters to a set of logical internal addresses for data access.

The host drive geometry parameters are mapped into an LBA based on this formula:

LBA	=	(HSCA - 1) + HHDA x HSPT + HNHD x HSPT x HCYA	(1)
	=	(HSCA - 1) + HSPT x (HHDA + HNHD x HCYA)	(2)
where	HSCA = Host Sector Address, HHDA = Host Head Address
	HCYA = Host Cylinder Address, HNHD = Host Number of Heads
	HSPT = Host Sectors per Track

The LBA is checked for violating the drive capacity. If it does not, the LBA is converted to physical drive cylinder, head and sector values. The physical address is then used to access or store the data on the disk and for other drive related operations.

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)

5 symbols, single burst, guaranteed

2 – 3

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Contents

HA RD Drive Produc T MA Nual DiamondMaxVL REV EC no Section Description Date Before You Begin U T I O NContents Product Specifications Handling and InstallationAT Interface Description Host Software InterfaceGlossary Interface CommandsService and Support Figures Manual Organization IntroductionMaxtor Corporation Abbreviations Key Words Signal Conventions Conventions NumberingDiamondMax VL 17 Key Features Product DescriptionProduct Features Functional / InterfaceDefect Management Zone DMZ On-the-Fly Hardware Error Correction Code ECCLogical Block Addressing Cache Management Major HDA Components Cylinder Limitation Subsystem ConfigurationJumper Location/Configuration Dual Drive SupportPerformance Specifications Product SpecificationsDrive Configuration Models and CapacitiesPhysical Dimensions Parameter Standard MetricEPA Energy Star Compliance Power RequirementsPower Mode Definitions Environmental LimitsReliability Specifications Shock and VibrationCanadian Emissions Statement Safety Regulatory ComplianceRadiated Electromagnetic Field Emissions EMC Compliance Pre-formatted Drive Handling and InstallationHard Drive Handling Precautions Important NoticeUnpacking and Inspection Multi-pack Shipping ContainerRepacking Physical InstallationRecommended Mounting Configuration System Requirements Handling PrecautionsTools for Installation Drive Identification InformationGeneral Requirements Hard Drive IdentificationInstalling in a Device Bay Systems Using Cable SelectInstalling 5.25-inch Mounting Brackets and Rails 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 AT Interface Description Interface ConnectorPIN Signal Pin Description SummaryPIN 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 Host Software Interface Error RegisterFeatures Register Task File RegistersCylinder Number Registers Sector Count RegisterSector Number Register Device/Head RegisterCommand Register Summary Command Name Command Code Parameters UsedTimer Value TIME-OUT Period Device Control Register Control Diagnostic RegistersAlternate Status Register Digital Input RegisterInterrupt Handling Reset and Interrupt HandlingReset Handling Interface Commands Set Feature CommandsRead Verify Sectors Read CommandsRead Sectors Read DMA Read MultipleWrite Sectors Write CommandsSet Multiple Mode Write Verify SectorsWrite Multiple Write DMAValue Description Set Feature CommandsSet Features Mode Power Mode Commands Sleep Mode Identify Drive Initialization CommandsWord Content Description 15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Error Code Description Seek, Format and Diagnostic CommandsExecute Drive Diagnostic Format TrackA.R.T. Command Set Execute S.M.A.R.TNo Quibble Service Service and SupportService Policy SupportInternet MaxFax ServiceCustomer Service Access Time GlossaryCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media