Bob,
Drivers are in the A/UX kernel and are the only pieces of software that can
access the hardware directly. A/UX provides an environment for what a Mac
driver (PRER) "sees". Because this environment does not allow hardware access,
it is possible that some Mac drivers return errors while initializing. You can
find more details in the A/UX manual: "A/UX Toolbox: Mac ROM Interface".
Did you go to the HPPER forum, someone from HP might be able to help you.
Alberic