Seagate ST3146855LC Cheetah 15K.5 SCSI Product Manual - Page 66

60

Cheetah 15K.5 SCSI Product Manual, Rev. H

Figure 14.

LC model drive physical interface (80-pin J1 SCSI I/O connector)

9.6.2

SCSI interface physical description

Cheetah 15K.5 SCSI drives support the physical interface requirements of the Ultra320 SCSI Parallel Inter-

face-4 (SPI-4), and operate compatibly at the interface with devices that support earlier SCSI-2 and SCSI-3

standards. 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 Ultra320 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 corresponding ANSI SPI document ref-

erenced in the preceding paragraph. These drives implement driver and receiver circuits that can operate

either SE or LVD. However, they cannot switch dynamically between SE and LVD operation.

The drives typically operate on a bus with other SCSI devices. All devices on the bus must operate in the same

mode, either SE or LVD, but not a mixture of these. All signals on the bus are common between all devices on

the bus. This bus 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 termina-

tion circuits that can be enabled by installation of a jumper plug (

TE

) on the device. These termination circuits

receive power from either a source internal to the device, or from a line in the interface cable specifically pow-

ered for that purpose. LC and LW model drives do not have onboard termination circuits. 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 the ANSI T10 Standard referenced above for the maximum number of

devices that can successfully operate at various interface transfer rates on SE and LVD buses.

LC 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 can-

not support the DC current needs of several drives, so no 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 recommended.

J6

80-pin

SCSI I/O

Connector

Pin 1

Section	Page
Cover	1
Contents	3
1.0 Scope	7
2.0 Applicable standards and reference documentation	9
2.1 Standards	9
2.1.1 Electromagnetic compatibility	9
2.1.2 Electromagnetic susceptibility	9
2.2 Electromagnetic compliance	10
2.3 European Union Restriction of Hazardous Substances (RoHS)	10
2.4 Reference documents	11
3.0 General description	13
3.1 Standard features	14
3.2 Media characteristics	14
3.3 Performance	15
3.4 Reliability	15
3.5 Formatted capacities	15
3.5.1 Programmable drive capacity	16
3.6 Factory installed accessories	16
3.7 Options (factory installed)	16
3.8 Accessories	16
4.0 Performance characteristics	17
4.1 Internal drive characteristics (transparent to user)	17
4.2 SCSI performance characteristics (visible to user)	17
4.2.1 Seek time	18
4.2.2 Format command execution time (minutes) [1]	18
4.2.3 Generalized performance characteristics	18
4.3 Start/stop time	19
4.4 Prefetch/multi-segmented cache control	19
4.5 Cache operation	19
4.5.1 Caching write data	20
4.5.2 Prefetch operation	20
5.0 Reliability specifications	21
5.1 Error rates	21
5.1.1 Recoverable Errors	21
5.1.2 Unrecoverable Error	21
5.1.3 Seek errors	22
5.2 Reliability and service	22
5.2.1 Annualized Failure Rate (AFR) and Mean Time Between Failures (MTBF)	22
5.2.2 Preventive maintenance	22
5.2.3 Hot plugging Cheetah 15K.5 SCSI disc drives	23
5.2.4 S.M.A.R.T.	23
5.2.5 Thermal monitor	25
5.2.6 Drive Self Test (DST)	25
5.2.6.1 DST Failure Definition	26
5.2.6.2 Implementation	26
5.2.6.2.1 State of the drive prior to testing	26
5.2.6.2.2 Invoking DST	26
5.2.6.2.3 Short and extended tests	26
5.2.6.2.4 Log page entries	27
5.2.6.2.5 Abort	27
5.2.7 Product warranty	27
6.0 Physical/electrical specifications	29
6.1 AC power requirements	29
6.2 DC power requirements	29
6.2.1 Conducted noise immunity	31
6.2.2 Power sequencing	31
6.2.3 Current profile	31
6.3 Power dissipation	33
6.4 Environmental limits	36
6.4.1 Temperature	36
6.4.2 Relative humidity	36
6.4.3 Effective altitude (sea level)	36
6.4.4 Shock and vibration	37
6.4.4.1 Shock	37
6.4.4.2 Vibration	39
6.4.5 Air cleanliness	39
6.4.6 Corrosive environment	39
6.4.7 Acoustics	40
6.4.8 Electromagnetic susceptibility	40
6.5 Mechanical specifications	40
7.0 Defect and error management	43
7.1 Drive internal defects	43
7.2 Drive error recovery procedures	43
7.3 SCSI systems errors	45
7.4 Background Media Scan	45
7.5 Media Pre-Scan	45
7.6 Deferred Auto-Reallocation	46
7.7 Idle Read After Write	46
8.0 Installation	47
8.1 Drive ID/option select header	47
8.1.1 Notes for Figures 10 and 11.	49
8.1.2 Function description	50
8.2 Drive orientation	51
8.3 Cooling	51
8.4 Drive mounting	52
8.5 Grounding	52
9.0 Interface requirements	53
9.1 General description	53
9.2 SCSI interface messages supported	53
9.3 SCSI interface commands supported	54
9.3.1 Inquiry Vital Product data	58
9.3.2 Mode Sense data	59
9.4 SCSI bus conditions and miscellaneous features supported	63
9.5 Synchronous data transfer	64
9.5.1 Synchronous data transfer periods supported	64
9.5.2 REQ/ACK offset	64
9.6 Physical interface	64
9.6.1 DC cable and connector	65
9.6.2 SCSI interface physical description	66
9.6.3 SCSI interface cable requirements	67
9.6.3.1 Cable requirements	67
9.6.4 Mating connectors	67
9.6.4.1 Mating connectors for LW model drives	68
9.6.4.2 Mating connectors for LC model drives	68
9.7 Electrical description	76
9.7.1 Multimode—SE and LVD alternatives	76
9.7.1.1 General cable characteristics	77
9.7.1.2 Single-ended drivers/receivers	77
9.7.1.3 Cables for low voltage differential drivers/receivers	78
9.8 Terminator requirements	79
9.9 Terminator power	79
9.10 Disc drive SCSI timing	80
9.11 Drive activity LED	82

Seagate ST3146855LC Cheetah 15K.5 SCSI Product Manual - Page 66

SCSI interface physical description

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