kicad-developers team mailing list archive

[Daniel Silverstone <dsilvers@xxxxxxxxxxxxxxxxx>]

On Wed, Mar 02, 2016 at 22:54:54 +0100, Nick Østergaard wrote:
> > If you consider the current situation regarding global labels and heirarchical
> > labels as "normal" then nothing I have done in my branch alters normal
> > behaviour.
> >
> > The intra-sheet link elements exist only to allow design engineers to mark
> > otherwise dangling wires as being meant to join (via net-name) to other wires
> > on the same sheet of the schematic.  If that net *also* has global or
> > heirarchical labels on it, then they shall behave exactly as before.
> >
> > Nothing I have done alters how the wires and pins end up grouped into nets, nor
> > alters how those nets then derive their names.  It's all for ERC and style checking.
> >
> > I hope that makes things a little more clear.
> 
> Yes, I understand that, but what I don't quite understand is what the
> result of your ERC will be in the case you have a local label on sheet
> A, then use the diamond marker on a dangling, but also connect a new
> global label to that net. Move to sheet B, use the global label and
> set the diamond or not on sheet B. Will it still report dangling nets?

Phew that took a while to follow, here's what I understand the scenario as:

There are two sheets in this design.  Sheet A has a wire labelled 'WIRE' one
end of which is a global label (let's say FOO) and the other end of which has
an intra-sheet link element on it.

Sheet B has a wire, one end of which has the global label FOO and the other of
which is either dangling or has an intra-sheet link element on it.

What I would expect and desire would be that if sheet A had no other
FOO-labelled net with an intra-sheet link on it, there'd be an ERC error; ditto
sheet B.  And that the intra-sheet link on A would not be matched by an
intra-sheet link on B.

So I tried it...

You had found a glorious corner case I had not considered.  Thank you.

I have pushed a small fix to my series which ensures that the expected
behaviour (that intra-sheet links do not satisfy one another across sheet
boundaries) is restored.  (I had failed to check m_SheetPath in my ERC :-)

Thank you.

D.


-- 
Daniel Silverstone                         http://www.digital-scurf.org/
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