Samsung spinpoint v40, 3.5" hard disk drives manual Read Multiple Command C4h

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DISK DRIVE OPERATION

6.4.13 Read Multiple Command (C4h)

The Read Multiple command performs similarly to the Read Sectors command. Interrupts are not generated on every sector, but on the transfer of a block which contains the number of sectors defined by a Set Multiple command.

Command execution is identical to the Read Sectors operation except that the number of sectors defined by a Set Multiple command are transferred without intervening interrupts. DRQ qualification of the transfer is required only at the start of the data block, not on each sector.

The block count of sectors to be transferred without intervening interrupts is programmed by the Set Multiple Mode command, which should be executed prior to the Read Multiple command. When the Read Multiple command is issued, the Sector Count register contains the number of sectors (not the number of blocks or the block count) requested.

If the number of requested sectors is not evenly divisible by the block count, as many full blocks as possible are transferred, followed by a final, partial block transfer. The partial block transfer shall be for n sectors, where

n = Remainder (Sector Count / Block Count)

If the Read Multiple command is attempted before the Set Multiple Mode command has been executed or when Read Multiple commands are disabled, then the Read Multiple operation is rejected with an Aborted Command error.

Disk errors encountered during Read Multiple commands are posted at the beginning of the block or partial block transfer, but DRQ is still set and the data transfer takes place as it normally would, including transfer of corrupted data, if any.

The contents of the Command Block registers, following the transfer of a data block, which had a sector in error, is undefined. The host should retry the transfer as individual requests to obtain valid error information.

Subsequent blocks or partial blocks are transferred only if the error was a correctable data error. All other errors cause the command to stop after transfer of the block, which contained the error. Interrupts are generated when DRQ is set at the beginning of each block or partial block.

64	SpinPoint V40 Product Manual

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Contents Spinpoint SpinPoint V40 Product Manual Table of Contents Ervo S Ystem EAD and W Rite O Perations Irmware F EaturesSmart Programming Requirements Protocol OverviewTiming Maintenance Precautions Service and Repair107 General InformationTable of Figures Page User Definition Manual OrganizationScope Commands and Messages Terminology and ConventionsComputer Message Format C/SReference Key Features IntroductionDescription Standards and Regulations Hardware RequirementsSpecification Summary SpecificationsPhysical Specifications Logical ConfigurationsPerformance Specifications Power Requirements 28.71Environmental Specifications SV6003H SV6014H SV8004HReliability Specifications Mtbf POHInstallation Space RequirementsUnpacking Instructions MountingOrientation 2Mounting Dimensions in Millimeters Clearance 3Mounting-Screw ClearanceCable Connectors DC Power ConnectorAT-Bus Interface Connector VentilationSpinPoint V40 Product Manual Jumper Block Configurations Options for Jumper Block Configuration Drive Installation 7DC Power Connector and AT-Bus Interface Cable ConnectionsSystem Startup Procedure ParameterSystem Setup Head / Disk Assembly HDA Base Casting AssemblyDC Spindle Motor Assembly Disk Drive OperationExploded Mechanical View Disk Stack Assembly Head Stack AssemblyVoice Coil Motor and Actuator Latch Assemblies Air Filtration SystemDigital Signal Process and Interface Controller Drive ElectronicsAT Disk Controller 2SID2001 AT Controller Block Diagram Host Interface Control Block Buffer Control Block Disk Control BlockSpinPoint V40 Product Manual Power Management Read/Write ICDisk ECC Control Block Frequency SynthesizerTime Base Generator Automatic Gain ControlAsymmetry Correction Circuitry ASC Analog Anti-Aliasing Low Pass Filter3Read/Write 88C5200 Servo System Read and Write OperationsRead Channel Firmware Features Write ChannelRead Caching Write Caching Defect Management Automatic Defect AllocationMulti-burst ECC Correction SmartBlank Signal Conventions Signal SummaryPhysical Interface Signal Descriptions DMACK- DMA Acknowledge Dmarq DMA RequestIntrq Drive Interrupt IOCS16- Drive 16-bit I/OPDIAG- Passed Diagnostics RESET- Drive ResetIordy I/O Channel Ready SD8 SD6 SD9 SD5 SD4SD3 SD2Drive Drive HostDIR Logical Interface GeneralBit Conventions EnvironmentSpinPoint V40 Product Manual Command Block Registers 2 I/O Register AddressControl Block Registers N N N A a aControl Block Register Descriptions Alternate Status Register 3F6hDrive Address Register 3F7h Device Control Register 3F6hCommand Block Register Descriptions Features Register 1F1hError Register 1F1h Data Register 1F0hCommand Register 1F7h Sector Count Register 1F2hCylinder High Register 1F5h Cylinder Low Register 1F4hStatus Register 1F7h BSY Drdy DWF DSC DRQ Corr IDX ERRAt Command Register Descriptions Command Parameter Used SpinPoint V40 Product Manual Check Power Mode 98h, E5h Execute Device Diagnostics 90hDownload Micro Code 92h Flush Cache E7h Format Track 50hIdentify Device ECh Word Content Description XxxxCapabilities Command set supported 95-128 0000h Reserved 129-159 Vendor specific 160-255 Idle 97h,E3h Idle Immediate 95h,E1hInitialize Device Parameters 91h Read Buffer E4h Read Long 22hwith retry, 23h without retryRead Multiple Command C4h Read Native Max Address F8h Read Sectors 20hwith retry, 21hwithout retryRead Verify Sectors 40hwith retry, 41hwithout retry Recalibrate 1xhSeek 7xh Set Features EFh ModeInputs LBANormal outputs BSY Drdy DRQ ERRDescription Set Multiple Mode C6h Sleep 99h, E6hSmart disable operation D9h Standby 96h,E2hSmart B0h Smart enable/disable attribute autosave D2h Smart enable operations D8hSmart execute off-line immediate D4h Smart read data D0h Byte DescriptionsValue Definition Off-line data collection capabilitySmart capability Smart read log sector D5hSmart return status DAh Smart save attribution value D3hStandby 96h, E2h Standby Immediate 94h, E0hWrite Buffer E8h Write DMA CAhWrite Multiple Command C5h Write Sectors 30hwith retry, 31hwithout retrySpinPoint V40 Product Manual Reset Response Error PostingProgramming Requirements Command Error Register Status Register BBKPower Conditions Sleep modeStandby mode Idle modeNormal mode PIO Data in Commands Protocol OverviewPIO Data Out Commands PIO Read CommandPIO Read Aborted Command PIO Write Command PIO Write Aborted CommandBSY=0 DRDY=1 BSY=1 BSY=0 DRQ=1 BSY=1 DRQ=0Non-Data Commands DMA Data Transfer Commands Aborted DMA Command Initialize DMA Reset DMA Status BSY=0 BSY=1BSY=1 BSY=0 Timing Register transfersDIOR-/DIOW Write PIO timing parameters Mode PIO data transfersAddr valid See note T1 t2 DIOR-/DIOW Multiword DMA data transfer DIOR-/DIOWMultiword DMA timing parameters Mode Ultra DMA data transfer Initiating an Ultra DMA data in burstUltra DMA data burst timing requirements 19Ultra DMA data burst timing requirementsSustained Ultra DMA data in burst 5Sustained Ultra DMA data in burstHost pausing an Ultra DMA data in burst 6Host pausing an Ultra DMA data in burstDevice terminating an Ultra DMA data in burst 7Device terminating an Ultra DMA data in burst 100Host terminating an Ultra DMA data in burst 8Host terminating an Ultra DMA data in burstInitiating an Ultra DMA data out burst 9Initiating an Ultra DMA data out burst 102Sustained Ultra DMA data out burst 10Sustained Ultra DMA data out burstDevice pausing an Ultra DMA data out burst 11Device pausing an Ultra DMA data out burst 104Host terminating an Ultra DMA data out burst 12Host terminating an Ultra DMA data out burstDevice terminating an Ultra DMA data out burst 13Device terminating an Ultra DMA data out burst 106Maintenance Precautions Service And RepairGeneral Information