HP 310X - Manual (Page 149)

USB light blinking green
for HP Jetdirect 175x external print server/Internet connector for USB
and HP Jetdirect 310x external print server/Internet connector for
USB
If the USB light is blinking green, it indicates that the print server
has detected a good connection to a valid USB device, but the print
server does not support the device. For example, this would happen if
you connected a USB digital camera to the print server.
This is not a fault, but rather an incompatibility between the print
server and the connected device. The print server supports only USB
printers (including USB multifunction printers and All-in-One
devices). It does not support non-printer USB devices, nor does it
support USB cable extenders, USB-to-parallel converters, or USB
hubs.
Please check that your print server is connected to a USB printer. If
your printer is not a USB printer, you will need to substitute a USB
printer or use a different model of HP Jetdirect print server (for
instance, one suitable for use with parallel printers).
Is the USB light now ON solid green?
If yes, click on the Yes button to return to the Troubleshooting
Overview page and continue with the next step of the troubleshooting
procedure.
If no, but you are connected to a USB printer, your print server has a
problem that requires assistance from HP Jetdirect technical support;
click on the No button for information on contacting HP.
©2000, 2001 Hewlett-Packard Company