Crystalfontz USB display/keypad

Hi all,

I have a few crystalfontz 633 series displays/keypads that have a USB interface and I was wondering if anyone has used something similar with an arduino UNO and can point me in the right direction to communicating with them. Technically, the usb interface is on a daughter board of the display and I could downgrade to straight serial rs232 if that makes my life easier. Any and all hints are greatly appreciated!