I doubt you will have any succes wiring it up to the empeg. Both are USB slave-devices and cannot communicate without a host. You are probably better of with an IR-keyboard, haven't heard of any success though. There was someone with such a keyboard last year on the BBS, I can't remember if he got it working.
Anyway, if you want to display console output on the empeg, you can go to my website for blitecho, which can output ascii characters on the display...

Frank van Gestel