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Universal Serial Bus ports
The system board in your server contains two Universal Serial Bus (USB) ports.
Each USB port has an external connector on the rear of the server for attaching
devices that previously used serial, parallel, keyboard, mouse, and game ports.
USB is an emerging serial interface standard for telephony and multimedia devices.
USB technology uses Plug and Play technology to determine what device is
attached to the connector. Each USB device is accessed by a unique USB
address. A device called a hub is used to convert the USB port 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 ft) per segment.
Note: If more than one USB device is to be attached, the device must be
connected to a hub.
Table 11 shows the pin-number assignments for the USB connectors.
Table 11. USB port pin-number assignments
Pin Signal
1 VCC
2
−
Data
3
+
Data
4 Ground
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IBM xSeries User's Reference