OK ，I 'd like to share the tips of setting up the USB Host on C3000.
1.Get a mini AB cable and plug your usb mass storage in it
2.Plug it iin C3000
3.Open terminal and type the following words
#bash 2.05 su
#mount /dev/sda1/ mnt / usbstorage
4.open your file manager to check if your usb mass storage is mount on C3000
Translated from USB Host On C3000