Serial Connectors; Ultra320 Scsi Connector; Universal Serial Bus Connectors - IBM IntelliStation M Pro 6220 User Manual

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.

Ultra320 SCSI connector

Your computer has an integrated 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 system board. The controller
has the following features:
v Double-transition clocking to achieve up to 320 MBps (mgegbytes per second)
v Domain name validation to negotiate compatible data-transfer speeds with each
v Cyclic-redundancy checking (CRC) to improve data reliability
v An active terminator for SCSI bus termination
SCSI cabling requirements
You can install four internal SCSI devices using the SCSI signal cable that comes
with some computer models. If you plan to attach external SCSI devices, you must
order an optional PCI 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 internal connectors" on page 52 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.

Universal Serial Bus connectors

There are six Universal Serial Bus (USB) 2.0 connectors, two on the front and four
on the rear of the computer. Use the USB connectors to connect optional telephony
and multimedia devices. USB 2.0 technology transfers data at up to 480 Mb per
second (Mbps) with a maximum of 127 external devices and a maximum signal
distance of 5 meters (16 ft) per segment (if the device that is attached to the
computer is a USB 2.0 device). If multiple USB devices are attached to the
computer, the USB hub must be USB 2.0; otherwise, all USB 2.0 devices will
transfer data at 12 Mbps. Using Plug and Play technology, USB devices are
configured automatically. The following illustration shows a USB connector.
Use a 4-pin USB cable to connect an external devices to a USB connector.
1 5
6 9
data-transfer rates
device
1 4
Chapter 4. Installing options
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