Maxtor 53073U6, 51024U2, 52049U4, 51536U3, 54098U8 specifications Read DMA

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INTERFACE COMMANDS

Read DMA

Multi-word DMA

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

1.The host initializes a slave-DMA channel prior to issuing the command,

2.Data transfers are qualified by DMARQ and are performed by the slave-DMA channel and

3.The drive issues only one interrupt per command to indicate that data transfer has terminated and status is available.

Ultra DMA

With the Ultra DMA Read protocol, the control signal (DSTROBE) that latches data from DD(15:0) is generated by the devices which drives the data onto the bus. Ownership of DD(15:0) and this data strobe signal are given DSTROBE to the drive during an Ultra DMA data in burst.

During an Ultra DMA Read burst, the drive always moves data onto the bus, and, after a sufficient time to allow for propagation delay, cable settling, and setup time, the sender shall generate a DSTROBE edge to latch the data. Both edges of DSTROBE are used for data transfers.

Any unrecoverable error encountered during execution of a Read DMA command terminates data transfer after the transfer of all sectors prior to the sector where the error was detected. The sector in error is not transferred. The drive generates an interrupt to indicate that data transfer has terminated and status is available. The error posting is identical to the Read Sector(s) command.

Read Multiple

Performs similarly to the Read Sector(s) command, except that for each READ MULTIPLE command data transfers are multiple sector blocks and the Long bit is not valid.

Execution is also similar to that of the READ SECTOR(S) command, except that:

1.Several sectors are transferred to the host as a block, without intervening interrupts.

2.DRQ qualification of the transfer is required only at the start of each block, not of each sector.

The block count consists of the number of sectors to be transferred as a block. (The block count is programmed by the Set Multiple Mode command, which must be executed prior to the Read Multiple command.) READ LONG command is limited to single sector requests.

When the Read Multiple command is issued, the Sector Count register contains the number of sectors requested — not the number of blocks or the block count. If the number of sectors is not evenly divisible by the block count, as many full blocks as possible are transferred, followed by a final, partial block transfer. This final, partial block transfer is for N sectors, where N = (sector count) modulo (block count)

The Read Multiple operation will be rejected with an Aborted Command error if attempted:

1.Before the Set Multiple Mode command has been executed, or

2.When Read Multiple commands are disabled.

The controller reports disk errors encountered during Read Multiple commands at the start of the block or partial block transfer. However, DRQ still sets, and the transfer occurs normally, along with the transfer of any corrupt data. Remaining block data from the following the sector in error is not valid.

If the Sector Count register contains 0 when the Set Multiple Mode command is issued, Read Multiple and Write Multiple commands are disabled; no error is returned. Once the appropriate action has been taken, the controller resets BSY and generates an interrupt. At power up, or after a hardware or software reset, Read Multiple and Write Multiple commands are disabled by default.

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Contents DiamondMax Plus U T I O N Before You BeginContents Handling and Installation Product SpecificationsDiamondmax Plus 40 Product Manual AT Interface Description Interface CommandsHost Software Interface Glossary Service and SupportFigures Abbreviations IntroductionMaxtorCorporation ManualOrganizationDiamondmax Plus 40 Introduction ConventionsProduct Description DiamondMax Plus 40 Key FeaturesMAX LBA Capacity Product FeaturesFunctional / Interface Model CYL SPTCacheManagement MajorHDAComponents CylinderLimitationJumperDescription SubsystemConfigurationJumper Location / Configuration Jumper ConfigurationModelsandCapacities ProductSpecificationsDriveConfiguration PerformanceSpecificationsProduct Specifications PhysicalDimensionsmaximumEnvironmentalLimits PowerRequirementsPowerModeDefinitions EPA Energy Star ComplianceShock and Vibration ReliabilitySpecificationsParameter Operating NON-OPERATING EMC/EMI SafetyRegulatoryComplianceHardDriveHandlingPrecautions HandlingandInstallationElectro-StaticDischargeESD UnpackingandInspection InstallationRepacking PhysicalInstallationHook up Before You BeginStart up Set upPinDescriptionSummary InterfaceConnectorPIN Signal ATInterfaceDescriptionPin Description Table PIN Name Signal Name Signal DescriptionAT Interface Description PIO Timing Timing Parameters ModeDMATiming Timing Parameters Mode 0 Mode 1 ModeUltra 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 Abrt TK0 Amnf HostSoftwareInterfaceTask File Registers Port Read WriteLBA DRV HS3 HS2 HS1 HS0 Contents LBA BitsBusy Drdy DSC DRQ ERR Host Software InterfaceCommandRegister SDH Command Name Command Code Parameters UsedTimer Value TIME-OUT Period SummaryIEN Control Diagnostic RegistersDS0 Reset and Interrupt Handling InterfaceCommands Interface Commands ReadCommandsRead DMA WriteCommands Write Multiple Value Description SetFeatureCommandsPowerModeCommands Timer Value TIME-OUT Period Word Content Description InitializationCommands15-8 = PIO data transfer mode Interface Commands Word Content Description Initialize Drive Parameters Error Code Description Seek,FormatandDiagnosticCommandsKey Register A.R.T. CommandSetSupport ServiceandSupportServicePolicy NoQuibble ServiceFrom Dial Service and SupportGlossary Errorcorrectioncodeecc CorrectableerrorDirectaccess DirectmemoryaccessFeedback HarderrorHeaddiskassemblyhda ExtrapulseLatewindow PhaselockedlooppllLandingzoneorlzone LatebitRecoverableerror PhasemarginRandomaccessmemoryram ReadgatesignalUnrecoverableerror SofterrorStrobeoffsetsignal UN-CORRECTABLEERROR
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