I'm considering the 990, which would be parked next to an HTPC should I decide to take the plunge. I'm wondering if I can send commands (switching inputs, etc.) from the PC via the USB/RS-232 ports -- I'd like to minimize the number of things which need to be automated with IR in my setup. I'm a programmer, so pointers (no pun intended) to protocol documentation and the like would be much appreciated.

Thanks in advance!