Ultrix device driver question

[George Robbins]

In article <23750 at usc.edu> weber at brand.usc.edu (Allan G. Weber) writes:
> 
> I have a MicroVAX-II (Ultrix 2.2) system that I am considering updating to
> Ultrix 3.1 or whatever is the latest version.  My problem is that the
> system has two non-DEC device drivers for handling some laboratory
> peripherals.
>              For one I only have an object file and it was written by a
> vendor who has since decided to not support Unix systems any more.  The
> other driver is for a DRV11W and I have sources to it.

If the vendor isn't interested in unix, then hopefully you can talk them
out of the sources.  Object modules aren't healthy, though you might luck
out.

>                                                       Both drivers had to
> be changed when we went from Ultrix 1.2 to 2.2.  Does anybody know if the
> rules for writing drivers changed again between version 2.2 and 3.x?  If
> so, I could use some advise on how to make the one I have sources for
> compatible with Ultrix 3.x.

I believe the major things that changed are 1) change over to a single memory
allocator (macro) for all kernel level memory allocation and 2) addition of
the "get device characteristics" IOCTL.  It may be that if your driver is
stupid enough (doesn't allocated memory) you can simply ignore these things.

>                               By the way, is there any Ultrix document on
> writing device drivers?  I've seen a similar document for VMS, but I've
> never seen one for Ultrix.

I'd check with DEC on this.  There *should* be some kind of internal document
or other describing the changes needed to convert drivers, but I've never seen
anything in the user documentation beyond little cryptic notes about the
"register declarations in probe routines" and "memory allocater changes".

-- 
George Robbins - now working for,     uucp:   {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing:   domain: grr at cbmvax.commodore.com
Commodore, Engineering Department     phone:  215-431-9349 (only by moonlite)