Pentax's lens mount and lens designations are rather confusing and one of the more common questions asked is if a given lens will fit a given body and what exposure modes will be available.
We have tried to answer this once and for all in the attached table, which is available for download in pdf form (attached) and as on a web page:
http://mosphotos.com/PentaxLensCompatibility.htm
It was a daunting task to complete the table, which primarily is based on reading of camera manuals, since we don't own but a few of the models.
Please let me know if you find any errors or omissions.
At least I learned something from this effort: I had always thought that A lenses are a safe bet and will work on any bayonet mount Pentax ever produced. Not so- there is one exception as the table shows!