IBM Netfinity 3500, Руководство пользователя

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Connecting External Options
Universal Serial Bus Ports
The universal serial bus (USB) is an emerging serial interface
standard for telephony and multimedia devices. Each USB port is a
single connector for devices that previously used serial, parallel,
keyboard, mouse, and game ports. USB technology uses Plug and
Play to determine which type of device has been attached to the
connector. Each USB device is accessed by a unique USB address.
A device called a hub is used to convert a single USB connector into
multiple attachment points. A hub has multiple ports where
peripherals can be attached. USB provides 12 megabits-per-second
(Mbps) bandwidth with a maximum of 63 peripherals and a
maximum signal distance of five meters per segment.
Note: If more than one USB device is to be attached, the device
must be connected to a hub. Your Netfinity 3500 server does
not support a keyboard attached to the system USB port.
Your Netfinity 3500 server comes with two USB ports. Table 8
shows the pin-number assignments for the USB port connectors.
Table 8. USB Port Connector Pin-Number Assignments
Pin Signal
1 VCC
2
−
Data
3
+
Data
4 Ground
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Netfinity 3500 User's Handbook