Multiple identical pins internally interconnected? Pcbnew can't see it


#41

It’s simple enough to draw wires to the pins

but then you have to route a path on the PCB between those pins, right? Otherwise DRC complains.


#42

read his post again.
The whole post not just the one line you quoted. And then read my post again. The whole post not the part of it that satisfies your bias in thinking that this task is unreasonable hard in kicad.

Have you done that?
What is the conclusion you come to?

I will help you.
It is easy if you make your footprint and symbol in such a way that this task is possible. Namely you need one pin in the schematic for each pin of the footprint. Then you can deside which pin you connect to wich part of your schematic. Of course if you draw a wire between these two (or more) internally connected pins, kicad assumes you want them connected on the pcb. But this is not what we told you to do.

Kicad and no other pcb tool i am aware of cares about the fact that something is internally connected. If you tell the programm in any way that two things are connected it will hold you to this decision by complaining about a non existing connection.


#43

Rene, read hist post, your post, my three hours old post and my previous post again. You’ll see I understand you all pretty well, I have even been using your suggested solution for almost two years now.

Yet Andy suggests something (“draw wires, that makes it clear”) that is weird - if by “draw wires to pins” Andy means to interconnect the internally connected pins then it breaks the idea of a bridge. If it means something else then it’s not clear to me - how can one draw wires to be clear yet not connect the pins?


#44

Yes andi was not as clear as he could have been. What he meant is (Or at least what i assume he meant):
Draw the wires as you want the connections to be on the PCB.


#45

If you draw a wire to a pin on the schematic, it indicates your intent to put a trace to that pin.


#46

Your custom switch symbol will need a red symbolic ‘wire’ going from one pin to another, the ones you intend to be connected, to tell people that this is intentional and you’re using the internal connection.
You do NOT draw a green ‘wire’ from one pin to the other in the schematic and nothing in the layout or the footprint.
Your schematic will have two distinct nets then at each pin, but looks logical and works within KiCAD now.

We have had discussions on this in the past, so it’s not new really.
The current symbol/schematic framework isn’t able to do this and the devs have been working hard to change that, but it’s still a lot to do.
At some point in the (far) future symbols and their pins will have more advanced features, that should enable to pre-tie symbol pins together and set up rules for this per symbol which would make this more elegant and enable ERC/DRC access to the intent of the designer (while keeping the different schools of thought possible @Andy_P mentions up there), but don’t hold your breath.


#47

symbol will need a red symbolic ‘wire’ going from one pin to another

Thanks for the clarification, now it makes perfect sense :slight_smile: