IBM PCI Dual Channel Ultra2 SCSI Adapter, Инструкция по установке и эксплуатации

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Chapter 1. Overview
This guide describes how to install the PCI Dual Channel Ultra2 SCSI Adapter in a
system unit with a PCI (peripheral compatible interface) bus. The PCI Dual Channel
Ultra2 SCSI Adapter enables you to use internal and external SCSI (small computer
system interface) 8 or 16 bit devices. Each channel operates independently as an
external LVD subsystem, an external single-ended or an internal singled-ended
device. Any two of these configurations can not run simultaneously. For more
information on connections, refer to Appendix A, “Connecting SCSI Devices to the
Adapter” on page A-1. The adapter conforms to the ANSI (American National
Standards Institute) SCSI standard and to the PCI local bus specification, Revision
2.1.
The PCI Dual Channel Ultra2 SCSI Adapter supports Ultra2 SCSI synchronous data
rates up to 40 MHz in Low Voltage Differential (LVD) operation. A 16-bit Ultra2 SCSI
device supports a maximum transfer rate of 80 megabytes (80,000,000 bytes) per
second. In single-ended ultra operation, a 16-bit SCSI device supports a maximum
transfer rate of 40 megabytes (40,000,000 bytes) per second. An 8-bit Fast SCSI
device supports a maximum transfer rate of 10 megabytes (10,000,000 bytes) per
second.
Attention: In single-ended operation, when the SCSI adapter detects any externally
attached device, the SCSI bus negotiates for a maximum 10MHz Fast SCSI. In AIX,
the automatic negotiation for 10MHz can be overridden using SMIT to reconfigure
the adapter. Refer to “Configuring the Ultra SCSI Adapter” on page 5-5 for more
information.
The use of internally and externally attached devices at the same time is not
supported with this adapter.
SCSI Connectors
The adapter has four SCSI connectors:
Ÿ
External connectors:
– Channel A (J2), Channel B (J3) internal, 68-position, high-density plastic
D-Shell VHDCI
Ÿ
Internal Connectors:
– Channel B (J4), Channel A (J6) internal, 68-position, high-density plastic
D-Shell SCSI standard connector for 16-bit attachment
Chapter 1. Overview
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