Maxtor 91536H2, 93073H4, 96147H8, 94610H6, 92305H3 specifications Read Commands

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INTERFACE COMMANDS

Read Commands

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 Before You Begin U T I O NContents Product Specifications AT Interface Description Service and Support Figures Manual Organization IntroductionMaxtor Corporation AbbreviationsConventions DiamondMax 60 Key Features Product DescriptionModel CYL Product FeaturesFunctional / Interface MAX LBA CapacityCache Management Major HDA Components Subsystem Configuration Jumper Location / ConfigurationCylinder Limitation Jumper Description Performance Specifications Product SpecificationsDrive Configuration Models and CapacitiesPhysical Dimensions maximum Parameter A N D a R D MetricEPA Energy Star Compliance Power RequirementsPower Mode Definitions Environmental LimitsReliability Specifications Shock and VibrationParameter E R a T I N G Safety Regulatory Compliance EMC/EMIHandling and Installation Hard Drive Handling PrecautionsElectro-Static Discharge ESD Unpacking and Inspection Multi-pack Shipping ContainerPhysical Installation RepackingBefore You Begin Hook upSet up Start upAT Interface Description Interface ConnectorPIN Signal Pin Description SummaryPIN Name Signal Name Signal Description Pin Description TableTiming Parameters Mode PIO TimingDMA Timing Ultra DMA Timing Timing Parameters all times in nanosecondsSustained 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 Host Software Interface Task File RegistersPort Read Write N T E N T S LBA Bits Command Register Summary R a M E T E R S U S E DControl Diagnostic Registers Reset and Interrupt Handling Interface Commands Read Commands Read DMA Write Commands Write Multiple Mode Set/Check Commands Value DescriptionEV E L Value M M a N D Power Mode Commands Timer Value TIME-OUT PeriodSleep Mode Initialization Commands Content Description15 -3 = reserved R D Content Description Initialize Drive Parameters Seek, Format and Diagnostic Commands Error Code DescriptionA.R.T. Command Set Key RegisterNo Quibble Service Service and SupportService Policy SupportFrom Dial Glossary BlockCorrectableerror Fetch Landingzoneorlzone Physicalsector Softerror
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