Seagate ST336605LW/LC/LCV Scsi interface physical description, Scsi interface cable requirements

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Cheetah 73LP Product Manual, Rev. E

9.6.2SCSI interface physical description

Cheetah 73LP drives support the physical interface requirements of the SCSI-3 Parallel Interface-3 (SPI-3) standards and operate compatibly at the interface with devices that support earlier SCSI-2 and SCSI-3 stan- dards. It should be noted that this is only true if the systems engineering has been correctly done, and if earlier SCSI-2 and SCSI-3 devices respond in an acceptable manner (per applicable SCSI Standards) to reject newer SCSI-3 protocol extensions that they don’t support.

The drives documented in this manual support single-ended and low voltage differential physical interconnects (hereafter referred to as SE and LVD, respectively) as described in the ANSI SPI-3 standard. These drives implement driver and receiver circuits that can operate either SE or LVD. However, they cannot switch dynami- cally between SE and LVD operation.

The drives typically operate on a daisy-chain interface in which other SCSI devices are also operating. Devices on the daisy chain must all operate in the same mode, either SE or LVD, but not a mixture of these. On the interface daisy chain, all signals are common between all devices on the chain, or bus, as it is also called. This daisy chain of SCSI devices must be terminated at both ends with the proper impedance in order to operate correctly. Do not terminate intermediate SCSI devices. In some cases, the SCSI devices at each end have onboard termination circuits that can be enabled by installation of a jumper plug (TE) on the device. These ter- mination circuits receive power from either a source internal to the device, or from a line in the interface cable specifically powered for that purpose. LC/LCV and LW/LWV model drives do not have onboard termination cir- cuits. Some type of external termination circuits must be provided for these drives by the end user or designers of the equipment into which the drives will be integrated. See Standard T10/1302D, sections 6.4 and 6.5 for the maximum number of devices that can successfully operate at various interface transfer rates on SE and LVD daisy chains.

LC/LCV model drives plug into PCBA or bulkhead connectors in the host. They may be connected in a daisy- chain by the host backplane wiring or PCBA circuit runs that have adequate DC current carrying capacity to support the number of drives plugged into the PCBA or bulkhead connectors. A single 80-pin I/O connector cable cannot support the DC current needs of several drives, so no daisy chain cables beyond the bulkhead connectors should be used. A single drive connected via a cable to a host 80-pin I/O connector is not recom- mended.

Table 11 shows the interface transfer rates supported by the various drive models defined in this manual.

Table 11: Interface transfer rates supported

Interface type/

Maximum transfer rate

 

 

 

 

 

 

 

 

 

 

drive models

Asynchronous

Fast-5

Fast-10

Fast-20

Fast-40

Fast-80

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SE

ST373405LC/LCV

yes

yes

yes

yes

no

no

 

ST373405LW/LWV

 

 

 

 

 

 

 

ST336605LC/LCV

 

 

 

 

 

 

 

ST336605LW

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LVD

ST373405LC/LCV

yes

yes

yes

yes

yes

yes

 

ST373405LW/LWV

 

 

 

 

 

 

 

ST336605LC/LCV

 

 

 

 

 

 

 

ST336605LW

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9.6.3SCSI interface cable requirements

The characteristics of cables used to connect SCSI-3 parallel interface devices are discussed in detail in sec- tion 6 of ANSI Standard T10/1302D. The cable characteristics that must be considered when interconnecting the drives described in this manual in a SCSI-3 parallel, daisy-chain interconnected system are:

•characteristic impedance (see Section 6.1)

•propagation delay (see Section 6.1)

•cumulative length (see Sections 6.4 and 6.5)

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Contents ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page Revision status summary sheet Revision Date Writer/Engineer Sheets AffectedPage Contents Defect and error management InstallationSeagate Technology support services Interface requirementsList of Figures Cheetah 73LP Product Manual, Rev. E ViiPage Scope Cheetah 73LP family drive ST373405LW shownCheetah 73LP Product Manual, Rev. E Applicable standards and reference documentation Korean MIC Australian C-TickTaiwanese Bsmi General description Cheetah 73LP family drive Cheetah 73LP Product Manual, Rev. E Standard features Media characteristicsPerformance ReliabilityFactory installed accessories Options factory installedAccessories user installed Unformatted and formatted capacitiesPerformance characteristics Start/stop time Ultra2 Scsi Ultra3 ScsiPrefetch/multi-segmented cache control Cheetah 73LP Product Manual, Rev. E Cache operation Caching write dataPrefetch operation Reliability specifications Reliability and service Preventive maintenanceService life Service philosophy7 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsReporting control Determining rateState of the drive prior to testing DST Failure DefinitionImplementation Invoking DSTShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesShipping Cheetah 73LP Product Manual, Rev. E Product warrantyProduct repair and return information Cheetah 73LP Product Manual, Rev. E AC power requirements Physical/electrical specificationsDC power requirements Conducted noise immunity Power sequencing3 12 V Current profile Typical ST336605 drive +12 V current profile Typical ST336605 drive +5 V current profile Amperes 000 900 800 700 600 Temperature Cheetah 73LP Product Manual, Rev. E Environmental limitsRelative humidity Effective altitude sea levelShock and vibration ShockRecommended mounting Vibration Air cleanlinessAcoustics LW and LWV mounting configuration dimensions LC and LCV mounting configuration dimensions Drive error recovery procedures Defect and error managementDrive internal defects Scsi systems errors Installation Configure drive optionsFormatting Drive ID/option select headerDo not install jumpers retain cover J5 jumper header on LW/LWV models only J2 option select header Cheetah 73LP Product Manual, Rev. E Function description Does not apply to LC/LCV modelDrive orientation CoolingCheetah 73LP Product Manual, Rev. E Drive mounting GroundingCheetah 73LP Product Manual, Rev. E Interface requirements Scsi interface messages supportedScsi interface commands supported Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Inquiry Vital Product data Mode Sense data DEF CHG Cheetah 73LP Product Manual, Rev. E Condition/feature supported by 2 REQ/ACK offset DC cable and connectorPhysical interface Pin Power Scsi interface physical description Scsi interface cable requirementsMating connectors Mating connectors for LW and LWV model drivesMating connectors for LC and LCV model drives ST373405LC/LCV and ST336605LC/LCVCheetah 73LP Product Manual, Rev. E Right-angle to Pcba connectors Scsi ID650±.005 155 100 346 Front View GND +DBP1 62Cheetah 73LP Product Manual, Rev. E REQ +REQ Electrical description LVD output characteristicsMultimode-SE and LVD alternatives General cable characteristics Single-ended drivers/receiversCables for low voltage differential drivers/receivers Terminator requirementsLC and LCV drives Disc drive Scsi timing Spindle status Command status LED status Drive activity LEDCheetah 73LP Product Manual, Rev. E Seagate Technology support services Online Services Automated ServicesPresales Support Technical SupportUSA/Canada/Latin America Support Services Customer Service CSOEuropean Support Services Asia/Pacific Support Services Africa/Middle East Support ServicesCall Center Toll-free Direct dial Cheetah 73LP Product Manual, Rev. E Index Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Scam Scsi Scsi ID 80Cheetah 73LP Product Manual, Rev. E
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