Copyrights and licenses for NIOS design

I'm working on a design using an Altera Cyclone and a NIOS processor.  I'm
having a little trouble working out exactly where things stand for
copyrights and licenses for the code, especially the NIOS software.

As I understand it, the intention of the Altera licensing is that I can use
the design and my code, along with the NIOS libraries, on any system I want
as long as the programable logic is an Altera device (which is fair enough).
However, I have a couple of questions about the details:

Each vhdl file generated from a schematic block has an Altera copyright
notice.  I presume I am free to add our my copyright notice to cover my own
additions to the module?

I presume I am free to use my own closed-source license on any software
modules I write, and link them to the NIOS libraries (including the plugs
libraries).  Am I able to include parts of Altera's example code in these,
and if so, do I need to add copyright clauses there?

What about using an open-source license (GPL in particular)?  Can I use
GPL'ed code in my software?  I am well aware that I would have to GPL my own
code that uses it, but what about the library code that is generated for the
NIOS?  Presumably I could not GPL that - is it okay to just make my own code
available as GPL'ed?

Thanks,

David



--
David

"I love deadlines.  I love the whooshing noise they make as they go past."
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