Hitachi HF-W2000 58 Instruction Manual page 34

6. USB Devices
Precautions
• Test a USB device before you start using it. Never use a USB device for a mission-critical purpose.
• Do not connect a USB device during OS startup, because the OS might not start normally.
• If you switch screens during OS startup when you use a CPU/USB KVM switch, the OS might not start normally
depending on the type of a CPU/USB KVM switch. When using a CPU/USB KVM switch, test its operation
thoroughly.
• For USB 2.0 and USB 3.0, the length of the cable that you use must be less than or equal to the length specified in
the specifications. Using longer cables might compromise transfer speed. Use a USB 2.0 or USB 3.0 cable that
matches the device you are using. If you do not do so, the actual transfer speed of the device might not be as high
as it should be, or communication errors might occur. For information about cable specifications, ask the
manufacturer of the cable. (For details about cable length, see 5.8.3 External interface cable length specifications.)
Required actions
• When using a USB port, check the orientation of the USB connector, and then insert the connector slowly to avoid
damaging the USB port.
• When a USB device is inserted, removed, or accessed, the system load might increase. If you need to use a USB
device during online operation (system operation), you must confirm that using the device does not affect the
currently running application software before using the device.
• After you clean a USB keyboard, check the connection between the equipment and the keyboard connector. A
loose connection might cause the keyboard to be incorrectly recognized or prevent the system from starting
normally.
Specifications
• Operation cannot be guaranteed in combination with all USB devices.
• Some USB devices do not conform to the USB specifications. If you turn off the main power while a non-
compliant USB device is connected, the equipment might not start properly, and the clock settings might be
corrupted. When selecting a USB device, test its operation thoroughly.
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