Asus PCI-SIU2, Руководство пользователя

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14 ASUS PCI-SIU2 User’s Manual
• If you have 8-bit SCSI peripherals, they must use SCSI IDs 0, 1, 2, 3,
4, 5, or 6. SCSI ID 0 is recommended for the first SCSI hard disk drive.
• In Windows 95/98, you can use the Device Manager to view the SCSI
ID (and other details) assigned to each SCSI device installed.
• Through ASUS’s SmartSCSI, you can use the utility to view the SCSI
ID (and other details) assigned to each SCSI device installed.
SCSI Bus Termination
The SCSI bus structure has a length limitation as well as a requirement for
termination at each end of the SCSI cable. The cable is designed to connect in
a daisy chain fashion. No branching is permitted in the SCSI bus. The first
and last physical SCSI device on the SCSI bus must be terminated (see Ca-
bling Examples). To ensure reliable communication on the SCSI bus, the ends
of the SCSI bus must be properly terminated. This is accomplished when the
peripheral at the end of each cable, or the end of the cable itself, has a termina-
tor installed (or enabled). The peripherals between the ends of each cable must
have its terminator removed (or disabled).
Since the method for terminating a SCSI peripheral can vary widely, refer to
the peripheral’s documentation for instructions on how to enable or disable
termination. Here are some general guidelines for termination:
• Internal Ultra2 peripherals are set at the factory with termination dis-
abled and cannot be changed. Proper termination for internal Ultra2
peripherals is provided by the built-in terminator at the end of the Ul-
tra2 internal SCSI cable.
• Termination on internal SCSI peripherals usually is controlled by manu-
ally setting a jumper or a switch on the peripheral, or by physically
removing or installing one or more resistor modules on the peripheral.
• Termination on external SCSI peripherals is usually controlled by in-
stalling or removing a SCSI terminator. On some external peripherals,
termination is controlled by setting a switch on the back of the drive.
• By default, termination on the PCI-SIU2 is automatic (the preferred
method). To manually set termination on the PCI-SIU2, see Host
Adapter Setup in Chapter 4.
• Most non Ultra2 SCSI peripherals come from the factory with termi-
nation enabled.
2. Getting Started