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

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INTERFACE COMMANDS

ReadCommands

Read Sector(s)

Reads from 1 to 256 sectors, as specified in the Command Block, beginning at the specified sector. (A sector count of 0 requests 256 sectors.) Immediately after the Command register is written, the drive sets the BSY bit and begins execution of the command. If the drive is not already on the desired track, an implied seek is performed.

Once at the desired track, the drive searches for the data address mark of the requested sector. The data address mark must be recognized within a specified number of bytes, or the Data Address Mark Not Found error will be reported. Assuming the data address mark is found:

1.The data field is read into the sector buffer.

2.Error bits are set (if an error was encountered).

3.The DRQ bit is set.

4.An interrupt is generated.

The DRQ bit is always set, regardless of the presence or absence of an error condition after the sector. Upon command completion, the Command Block registers contain the numbers of the cylinder, head and sector of the last sector read. Back-to-back sector read commands set DRQ and generate an interrupt when the sector buffer is filled at the completion of each sector. The drive is then ready for the data to be read by the host. DRQ is reset and BSY is set immediately when the host empties the sector buffer.

If an error occurs during Read Sector commands, the read terminates at the sector where the error occurred. The host may then read the Command Block to determine the nature of that error, and the sector where it happened. If the error type is a correctable or an non-correctable data error, the flawed data is loaded into the sector buffer.

A Read Long command sets the Long bit in the command code and returns the data and the ECC bytes in the data field of the specified sector. During a Read Long, the drive does not check the ECC bytes to determine if there has been a data error. The Read Long command is limited to single sector requests.

Read Verify Sector(s)

Identical to the Read Sector(s) command, except that:

1.DRQ is never set,

2.No data is transferred back to the host and

3.The long bit is not valid.

7 – 2

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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 Abbreviations IntroductionMaxtorCorporation ManualOrganizationConventions Product Description KeyFeaturesFunctional / Interface Product FeaturesModel S SP T MAX LB a Apac IT Y CacheManagement MajorHDAComponents Jumper Location / Configuration SubsystemConfigurationCylinderLimitationJumperDescription ModelsandCapacities ProductSpecificationsDriveConfiguration PerformanceSpecificationsAram E TE R Stan D ARD ME T RIC PhysicalDimensionsmaximumEnvironmentalLimits PowerRequirementsPowerModeDefinitions EPA Energy Star ComplianceShock 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 upPIN IGN AL InterfaceConnectorATInterfaceDescription PinDescriptionSummaryPin 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. CommandSetSupport ServiceandSupportServicePolicy NoQuibbleServiceFrom Dial Glossary AccesstimeCorrectableerror Fetch Landingzoneorlzone Physicalsector Softerror
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