Maxtor 51536H2, 52049H3, 53073H4, 546106 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 Corporate Headquarters REV EC N O SEC Tion Desc Ription ATE Before You Begin U T I O NContents Product Specifications Handling and InstallationHost Software Interface Interface CommandsAT Interface Description Service and Support GlossaryFigures Introduction MaxtorCorporationManualOrganization AbbreviationsConventions KeyFeatures Product DescriptionModel S SP T MAX LB a Apac IT Y Product FeaturesFunctional / Interface CacheManagement MajorHDAComponents CylinderLimitationJumperDescription SubsystemConfigurationJumper Location / Configuration ProductSpecifications DriveConfigurationPerformanceSpecifications ModelsandCapacitiesPhysicalDimensionsmaximum Aram E TE R Stan D ARD ME T RICPowerRequirements PowerModeDefinitionsEPA Energy Star Compliance EnvironmentalLimitsParam E TE R OP ER AT ING ON- OPE R AT ING ReliabilitySpecificationsShock and Vibration SafetyRegulatoryCompliance EMC/EMIElectro-StaticDischargeESD HandlingandInstallationHardDriveHandlingPrecautions UnpackingandInspection Multi-pack Shipping ContainerPhysicalInstallation RepackingBefore You Begin Hook upSet up Start upInterfaceConnector ATInterfaceDescriptionPinDescriptionSummary PIN IGN ALPIN Name Signal Name Signal Desc Ription Pin Description TableIM in G Paramet ERS Mode PIO TimingImin G Paramet ERS Mode DMATimingUltra DMA Timing ModeSustained 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 POR T EAD WR ITE HostSoftwareInterfaceTask File Registers Conten TS LBA Bits CommandRegister Summary 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 DControl Diagnostic Registers Reset and Interrupt Handling InterfaceCommands ReadCommands Read DMA WriteCommands Write Multiple LE VE L ModeSet/CheckCommandsVAL UE DES C RIP Tion VAL UE Omman D PowerModeCommands Timer VAL UE TIME-OUT PeriodSleep Mode InitializationCommands Or D ENT Desc RiptionOr D 15- 10, as c urrently defined Initialize Drive Parameters Seek,FormatandDiagnosticCommands ER ROR Code Desc RiptionA.R.T. CommandSet Key RegisterServiceandSupport ServicePolicyNoQuibbleService SupportFrom Dial Accesstime GlossaryCorrectableerror Fetch Landingzoneorlzone Physicalsector Softerror
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