IBM eServer 250 xSeries, Руководство пользователя

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IBM® xSeries 250: User’s Reference
Universal Serial Bus ports
Your server has two Universal Serial Bus (USB) ports that configure automatically.
USB is an emerging serial interface standard for telephony and multimedia devices. It
uses Plug and Play technology to determine the type of device attached to the
connector.
Notes:
1. If you attach a standard (non-USB) keyboard to the keyboard connector, the USB
ports and devices will be disabled during the power-on self-test (POST).
2. If you install a USB keyboard that has a mouse port, the USB keyboard emulates a
mouse and you will not be able to disable the mouse settings in the
Configuration/Setup Utility program.
3. Check to make sure that your NOS supports USB devices.
USB cables and hubs
You need a 4-pin cable to connect devices to USB 1 or USB 2. If you plan to attach
more than two USB devices, you must use a hub to connect the devices. The hub
provides multiple connectors for attaching additional external USB devices.
USB technology provides up to 12 megabits-per-second (Mbps) speed with a
maximum of 127 external devices and a maximum signal distance of five meters (16
ft.) per segment.
USB-port connectors
Each USB port has an external connector on the rear of the server for attaching USB
compatible devices.
The following table shows the pin-number assignments for the USB-port connectors
on the rear of your server.
Pin Signal
1 VCC
2 -Data
3 +Data
4 Ground
Table 13. USB-port connector pin-number assignments.