Maxtor 51536U3, 51024U2, 52049U4, 53073U6, 54098U8 specifications ReadCommands, Interface Commands

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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 DiamondMax Plus Before You Begin U T I O NContents Product Specifications Handling and InstallationDiamondmax Plus 40 Product Manual Interface Commands AT Interface DescriptionHost Software Interface Service and Support GlossaryFigures ManualOrganization IntroductionMaxtorCorporation AbbreviationsConventions Diamondmax Plus 40 IntroductionDiamondMax Plus 40 Key Features Product DescriptionModel CYL SPT Product FeaturesFunctional / Interface MAX LBA CapacityCacheManagement MajorHDAComponents Jumper Configuration SubsystemConfigurationJumper Location / Configuration CylinderLimitationJumperDescriptionPerformanceSpecifications ProductSpecificationsDriveConfiguration ModelsandCapacitiesPhysicalDimensionsmaximum Product SpecificationsEPA Energy Star Compliance PowerRequirementsPowerModeDefinitions EnvironmentalLimitsReliabilitySpecifications Shock and VibrationParameter Operating NON-OPERATING SafetyRegulatoryCompliance EMC/EMIHandlingandInstallation HardDriveHandlingPrecautionsElectro-StaticDischargeESD Installation UnpackingandInspectionPhysicalInstallation RepackingBefore You Begin Hook upSet up Start upATInterfaceDescription InterfaceConnectorPIN Signal PinDescriptionSummaryPIN Name Signal Name Signal Description Pin Description TableAT Interface Description Timing Parameters Mode PIO TimingTiming Parameters Mode 0 Mode 1 Mode DMATimingMode 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 Port Read Write HostSoftwareInterfaceTask File Registers Abrt TK0 AmnfHost Software Interface Contents LBA BitsBusy Drdy DSC DRQ ERR LBA DRV HS3 HS2 HS1 HS0CommandRegister Summary Command Name Command Code Parameters UsedTimer Value TIME-OUT Period SDH Control Diagnostic Registers IEN DS0 Reset and Interrupt Handling InterfaceCommands ReadCommands Interface CommandsRead DMA WriteCommands Write Multiple SetFeatureCommands Value DescriptionPowerModeCommands Timer Value TIME-OUT Period InitializationCommands Word Content Description15-8 = PIO data transfer mode Interface Commands Word Content Description Initialize Drive Parameters Seek,FormatandDiagnosticCommands Error Code DescriptionA.R.T. CommandSet Key RegisterNoQuibble Service ServiceandSupportServicePolicy SupportService and Support From DialGlossary Directmemoryaccess CorrectableerrorDirectaccess ErrorcorrectioncodeeccExtrapulse HarderrorHeaddiskassemblyhda FeedbackLatebit PhaselockedlooppllLandingzoneorlzone LatewindowReadgatesignal PhasemarginRandomaccessmemoryram RecoverableerrorUN-CORRECTABLEERROR SofterrorStrobeoffsetsignal Unrecoverableerror
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