ATTO Technology ExpressPCI UL5D Instrukcja instalacji i obsługi - Strona 13
Przeglądaj online lub pobierz pdf Instrukcja instalacji i obsługi dla Adapter hosta ATTO Technology ExpressPCI UL5D. ATTO Technology ExpressPCI UL5D 19 stron. Single channel ultra320 scsi, pci-x host adapter dual channel ultra320 scsi, pci-x host adapter dual channel ultra320 scsi, pci express host adapter dual channel ultra320 scsi, low-profile pcie host adapter
Również dla ATTO Technology ExpressPCI UL5D: Specyfikacja techniczna (2 strony), Specyfikacja techniczna (2 strony), Instrukcja rozwiązywania problemów (12 strony)
Drukuj stronę
• Use an LVD terminator if you are only using LVD
devices.
Although you can use a Single-Ended
terminator, all devices will be limited to Ultra
SCSI speeds. Single-Ended devices require
a Single-Ended terminator.
If you use an LVD terminator with Single-
Ended devices, the system may hang or
devices may not be seen on the SCSI bus.
Some termination manufacturers provide
automatically sensing terminators.
• External terminators should be attached to the
last external device in the SCSI chain.
Don't use any other termination on the
external SCSI chain.
The last device on an internal SCSI chain
should also be terminated in one of several
ways.
Many Single-Ended Ultra SCSI and earlier
devices provide a jumper setting for applying
termination: place a jumper over the pins
designated for termination on the last device
on the internal cable. Check with your drive
manufacturer if you are not sure which pins
to use.
• LVD Ultra2 and Ultra160 SCSI devices cannot
supply their own termination.
Use an internal ribbon cable which has a
SCSI terminator attached to the end of it,
connect the unterminated end of the cable to
the host adapter card and the internal drives
to the subsequent connectors.
The terminator should be at the opposite end
of the cable from the host adapter card.
• Wide (16-bit) and Narrow (8-bit) devices can be
connected together on the same connector of
the host adapter card, but wide devices must be
attached first, followed by narrow devices.
To terminate the SCSI bus, the cable or
adapter used to convert from a wide (68-pin)
connector to a narrow (50-pin) connector
provides partial termination, allowing upper
8-bits (or byte) of the wide SCSI bus to be
properly terminated.
A narrow terminator should be used on the
last narrow device to terminate the rest of the
SCSI bus.
A SCSI bus without partial termination
between the wide and narrow devices may at
first appear to work correctly, but occasional
I/O errors occur without proper termination.
• If you use both internal and external connectors
and mix Single-Ended and LVD devices on the
same bus, even if using different connectors, the
host adapter card will operate with Single-Ended
signaling at UltraSCSI speeds.
• Automatic termination
When both internal and external connectors
are used, the host adapter card detects the
presence of devices and turns off
termination.
If devices are removed from one connector
of the card, the host adapter automatically
detects the change, and enables its own
termination.
• Software controlled termination
You may have to override the host adapter's
automatic termination if only narrow devices
are attached to one connector and wide
devices are attached to the other connector
on the same bus.
The host adapter must supply partial
termination to the upper 8-bits (byte), but not
automatically.
Please refer to your ExpressPCI Utilities
manual for instructions on setting the host
adapter's termination to Upper Byte.
• Termination power
Host adapters supply termination power to
the bus at all times and many SCSI devices
are also able to supply termination power.
SCSI signal quality, particularly with long or
marginal quality cables, may be improved if
the device supplies the termination power.
Contact your device manufacturer for more
information on your device's ability to supply
termination power.
8
Cabling and termination