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

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INTERFACE COMMANDS

Set Multiple Mode

Enables the controller to perform Read and Write Multiple operations, and establishes the block count for these commands. Before issuing this command, the Sector Count register should be loaded with the number of sectors per block. The drives support block sizes of 2, 4, 8 and 16 sectors.

When this command is received, the controller sets BSY and examines the Sector Count register contents. If they contain a valid and supported block count value, that value is loaded for all subsequent Read and Write Multiple commands, and execution of those commands is enabled. An invalid and unsupported block count in the register results in an Aborted Command error and disallows Read Multiple and Write Multiple commands.

WriteCommands

Write Sector(s)

Writes from 1 to 256 sectors, beginning at a sector specified in the Command Block. (A sector count of 0 requests 256 sectors.)

When the Command register is written, the drive sets the DRQ bit and waits for the host to fill the sector buffer with the data to be written. An interrupt is not generated to start the first buffer fill operation.

Once the buffer is full, the drive resets DRQ, sets BSY, and begins command execution. If the drive is not already on the desired track, an implied seek is performed.

The data loaded in the buffer is written to the data field of the sector, followed by the ECC bytes. Upon command completion, the Command Block registers contain the cylinder, head and sector number of the last sector written. The next time the buffer is ready to be filled during back-to-back Write Sector commands, DRQ is set and an interrupt is generated.

After the host fills the buffer, DRQ is reset and BSY is set. If an error occurs, Write Sector operations terminate at the sector containing the error.

The Command Block registers then contain the numbers of the cylinder, head and sector where the error occurred. The host may read the Command Block to determine the nature of that error, and on which sector it happened. A Write Long may be executed by setting the Long bit in the command code. The Write Long command writes the data and the ECC bytes directly from the sector buffer; the drive itself does not generate the ECC bytes. Restrict Write Long commands to PIO Mode 0.

Write Verify Sector(s)

Identical to the Write Sector(s) command, except that the requested sectors are verified immediately after being written. The verify operation reads (without transferring), and checks for data errors. Any errors encountered during this operation are reported.

Write Sector Buffer

Allows the host to overwrite the contents of the drive’s sector buffer with a selected data pattern. When this command is received, the drive:

1.Sets BSY,

2.Sets up the sector buffer for a write operation,

3.Sets DRQ,

4.Resets BSY and

5.Generates an interrupt.

The host may then write up to 256 words of data to the buffer. A disk write task begins to store the host data to disk. Host write commands continue to be accepted and data transferred to the buffer until either the write command stack is full or the data buffer is full. The drive may reorder write commands to optimize drive throughput.

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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 SpecificationsInterface Commands AT Interface DescriptionHost Software Interface Glossary Service and SupportFigures MaxtorCorporation IntroductionManualOrganization AbbreviationsConventions Product Description KeyFeaturesProduct Features Functional / InterfaceModel S SP T MAX LB a Apac IT Y CacheManagement MajorHDAComponents SubsystemConfiguration Jumper Location / ConfigurationCylinderLimitationJumperDescription DriveConfiguration ProductSpecificationsPerformanceSpecifications ModelsandCapacitiesAram E TE R Stan D ARD ME T RIC PhysicalDimensionsmaximumPowerModeDefinitions PowerRequirementsEPA Energy Star Compliance EnvironmentalLimitsReliabilitySpecifications Shock and VibrationParam E TE R OP ER AT ING ON- OPE R AT ING EMC/EMI SafetyRegulatoryComplianceHandlingandInstallation HardDriveHandlingPrecautionsElectro-StaticDischargeESD Multi-pack Shipping Container UnpackingandInspectionRepacking PhysicalInstallationHook up Before You BeginStart up Set upATInterfaceDescription InterfaceConnectorPinDescriptionSummary PIN IGN ALPin 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 HostSoftwareInterface Task File RegistersPOR 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 ModeSet/CheckCommands VAL UE DES C RIP TionLE 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. CommandSetServicePolicy ServiceandSupportNoQuibbleService SupportFrom Dial Glossary AccesstimeCorrectableerror Fetch Landingzoneorlzone Physicalsector Softerror