[oc] hardware compatibility and patent infringement

[ABP <ab@cataloniamail.com>]

Hi all,

As some people in Opencores are developing cores compatibles with
designs protected by patents and copyrights I thought it was a good idea
to ask about "hardware compatibility and patent infringement" in this
mailing list.

I would appreciate any information/answer you could give to the
following questions:

1. In general, What's the way to design a hardware processor (device)
compatible with the instruction set (specifications) of another
processor (device) without infringement of patents?

2. If someone implements a processor compatible with the instruction set
of another processor but without copying anything else from that
original processor apart from the original instruction set, will that be
patent infringement?

Please, point me to any good source of information on the matter that
you might know.

Thanks for your time.

A. Petit