IBM 865951Y - Netfinity 5000 - 51Y, Руководство по техническому обслуживанию аппаратной части

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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
technology 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 (16 feet 4.9
inches) per segment.
Note
If more than one USB device is to be attached, the
devices must be connected to a hub. The Netfinity
5000 does not support a keyboard attached to the
system USB port.
The Netfinity 5000 comes with two USB ports. Table 13
shows the pin-number assignments for the USB port
connectors.
Table 13. USB Port Connector Pin-Number
Assignments
Pin Signal
1 VCC
2
−
Data
3
+
Data
4 Ground
Netfinity 5000 - Type 8659
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