IBM DDRS-39130 - Ultrastar 9.1 GB Hard Drive

6.1.2 SCSI Cable
| 6.1.2.1 SE model
The maximum cumulative cable length when using single-ended transceiver should be 3 meters. Implementa-
tions that limit the transfer rate to a maximum of 5 Mbyte transfers per second may extend the cumulative
cable length to 6 meters. (ANSI SCSI-3 X3T10/855D Revision 15a).
The maximum cumulative signal path between terminators shall be 3.0 meters when using up to 4 maximum
capacitance (25pF) devices. The maximum cumulative signal path length between terminators shall be 1.5
meters when using from five to eight maximum capacitance devices. (ANSI SCSI-3 FAST-20
X3T10/1071D).
| 6.1.2.2 LVD model
| The maximum cumulative cable length when using LVD transcever must be 12 meter. For the details of
| specification, refer to ANSI SCSI Parallel Interface-2 (SPI-2) T10 Project 1142D Revision 19.
6.1.3 SCSI Bus Terminator
| 6.1.3.1 SE model
Single-ended 50 and 68 pin models have active termination feature. The function can be enabled by
installing a jumper between pins 13 and 14 of the jumper block, or connecting pins 9 and 10 of the auxiliary
connector on 68 SCSI pin models. System is responsible for making sure that all required signals are termi-
nated at both ends of the bus cable.
Term.power (#26 pin of 50pin model, #17,18 pins of 68pin model) is provided by drive 5V supply through
current limiter and shotky diode, and internal terminator is also driven by this power line. It is not change-
able.
The 80-pin (SCA-2) model does not have internal terminator.
|
6.1.3.2 LVD model
| Both 68-pin and 80-pin of LVD model have not SCSI Terminator nor Terminator Power.
| It is user responsibility to make sure that all required signals are adequately terminated at both ends of the
| bus cable.
6.1.4 Hot Plug / Unplug
The 80-pin (SCA-2) model supports Hot Plug/Unplug.
The 50-pin model and 68-pin model do not support Hot Plug/Unplug.
Specification 27