Maxtor 6800 manual Logical Block Addressing, Defect Management Zone DMZ, Software ECC Correction

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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

Software ECC Correction

22 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.

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Contents HA RD Drive Produc T MA Nual DiamondMax U T I O N Before You BeginContents Handling and Installation Product SpecificationsHost Software Interface AT Interface DescriptionService and Support Interface CommandsGlossary Figures Maxtor Corporation IntroductionManual Organization AbbreviationsConventions Signal ConventionsKey Words NumberingProduct Description DiamondMax 6800 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 RequirementsEPA Energy Star Compliance Environmental LimitsShock and Vibration Reliability SpecificationsRadiated Electromagnetic Field Emissions EMC Compliance Safety Regulatory ComplianceCanadian Emissions Statement Hard Drive Handling Precautions Handling and InstallationPre-formatted Drive Important NoticeMulti-pack Shipping Container Unpacking and InspectionRecommended Mounting Configuration Physical InstallationRepacking 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 CablesSetting the Bios Cmos System SetupBios Cmos Parameters Hard Drive Preparation System Hangs During Boot AT Interface Description Interface ConnectorPin 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 Handling Reset and Interrupt HandlingInterrupt Handling Set Feature Commands Interface CommandsRead Sectors Read CommandsRead 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 Execute Drive Diagnostic Seek, Format and Diagnostic CommandsFormat Track Execute S.M.A.R.T A.R.T. Command SetService Policy Service and SupportNo Quibble Service SupportCustomer Service MaxFax ServiceInternet Glossary Access TimeCylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media