Maxtor 2R015H1, 2R010H1 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 Hard Disk Drive Specifications Models 2R015H1 & 2R010H1 Before You Begin U T I O NContents Product Specifications Handling and InstallationInterface Commands AT Interface DescriptionHost Software Interface Service and Support GlossaryFigures ManualOrganization IntroductionMaxtorCorporation AbbreviationsConventions Key Features Product DescriptionProduct Features Functional / InterfaceCacheManagement Major HDA Components SubsystemConfiguration Jumper Location / ConfigurationCylinder Limitation Jumper Description PerformanceSpecifications ProductSpecificationsDrive Configuration Models and CapacitiesPhysical Dimensions EPA Energy Star Compliance PowerRequirementsPower Mode Definitions Environmental LimitsReliability Specifications Shock and VibrationSafety Regulatory Compliance EMC/EMIHandlingandInstallation HardDriveHandlingPrecautionsElectro-StaticDischargeESD UnpackingandInspection Multi-pack Shipping ContainerPhysicalInstallation RepackingBefore You Begin Hook upSet up Start upPinDescriptionSummary InterfaceConnectorATInterfaceDescription 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 HostSoftwareInterface Task File RegistersPOR T EAD WR ITE Conten TS LBA Bits CommandRegister Seek, Format, and Diagnostic CommandsSummary 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 ModeSet/CheckCommands VAL UE DES C RIP TionLE VE L 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 RegisterNo Quibble Service ServiceandSupportService Policy Product SupportFrom Dial Glossary Channel Correctable errorCentral processing unit CPU CharacterError correction code ECC Direct accessDirect memory access DMA Error freeFrequency response Hard errorHead disk assembly HDA Gigabyte GBLogic Late windowLatency Logical addressRandom access memory RAM Phase locked loop PLLPhase margin Read gate signalSequential access Sector pulse signalSeek complete signal Soft errorUnrecoverable error Strobe offset signalUn-correctable error Write gate signal