Pentax KX

My freind showed me an old KM serries and was wondering if her old lenses fitted on to my K10D. We tries, and they did. But i was getting
F--- Flashing up...What does this mean?

If she decided to by the K20D, would her existing lenses fit? or would she have to buy an adapter?

Help much appreciated.

The existing lenes will work fine. You need to enable 'use aperture ring' in the menu. You can then use AV or Manual with these.

Thanks very much Gareth. She will be well happy now.
Cheers.

The "F--" that you see in the display is where the aperture value would normally show up. The older lenses (pre-A series) have no electronic communication with the body so the camera has no way of knowing what aperture you've selected, hence F--