laptop keyboard trouble

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

Just trying to install netbsd on a brand new laptop by booting from an
external usb-connected hard disk. I get

  boot device: <unknown>
  root device:

and as soon as try to type the root device:

  pckbport_start: command error

and "game over". Thoughts?
(this is a few months old -current/i386 on a intel i5 laptop)

Cheers,

Patrick