IBM IntelliStation M Pro 6225, Руководство пользователя

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Serial connectors
There are two serial connectors on the rear of the computer. Use these connectors
to connect serial devices. The following illustration shows a serial connector.
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Ultra320 SCSI connector
Your computer might have a mini-PCI SCSI controller. This single-channel controller
supports an independent, Ultra320 SCSI channel that supports up to 15 SCSI
devices. The SCSI connector for the channel is on the mini-PCI SCSI controller.
The controller has the following features:
v
Double-transition clocking to achieve up to 320 MBps (megabytes per second)
data-transfer rates
v
Domain name validation to negotiate compatible data-transfer speeds with each
device
v Cyclic-redundancy checking (CRC) to improve data reliability
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An active terminator for SCSI bus termination
The following illustration shows a SCSI connector.
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SCSI cabling requirements
You can install three internal SCSI devices using the SCSI signal cable that comes
with some computer models. If you plan to attach external SCSI devices, you can
order an optional SCSI adapter and external cable. To select and order the correct
cables for use with external devices, contact your IBM marketing representative or
authorized reseller. To receive an indication of SCSI hard-disk drive activity, you
must also connect the SCSI adapter to the SCSI LED connector on the system
board. See “System-board option connectors” on page 31 for the locations of the
SCSI connectors.
Setting SCSI IDs
Each SCSI device that is connected to a SCSI controller must have a unique SCSI
ID. This ID enables the SCSI controller to identify the device and ensure that
different devices on the same SCSI channel do not attempt to transfer data
simultaneously. SCSI devices that are connected to different SCSI channels can
have duplicate SCSI IDs. See the information that comes with the device for
instructions for setting its SCSI ID.
Chapter 4. Installing options
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