Message-ID: <525AADB0.8030508@penguindevelopment.org>
Date: Sun, 13 Oct 2013 16:26:56 +0200
From: Peter <link AT penguindevelopment DOT org>
Organization: Penguin Development
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To: geda-user AT delorie DOT com
Subject: [geda-user] Dealing with internal connections
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Reply-To: geda-user AT delorie DOT com

Some components (e.g. standard 4-pin tactile switches) have internal 
connections between pins, which is a feature I sometimes want to exploit 
to make routing easier.

To deal with that, I've so far just given the internally connected pins 
the same name; when you connect just one of the pins, PCB will complain 
that the other one isn't connected, which can be worked around by 
connecting them with a trace on a "fake connection" layer.

Now, however, I want to do the same with a surface mount component. The 
"fake connection" trick doesn't work there, because all connections need 
to be on the same side as the pads, so I'm wondering if there's a better 
way to do it that doesn't involve heavy editing of the schematic, and 
that will still stop PCB from telling me I need to connect the pads.

So basically, suppose I have, for example, a surface-mounted tactile 
switch as follows:

1a |__| 2a
    |##|
    |##|
1b |¯¯| 2b

Pads 1a and 1b are internally connected and are both called "1" in the 
footprint. In the schematic, I just have a 2-pin switch. I'd like for 
PCB to recognise a connection to either pad 1a or 1b as a connection to 
*both* pads, without having to edit my schematic to make all of the 
switches have 4 pins. (That problem with that would be that I'd have to 
edit the schematic a lot during the PCB design process, which I want to 
avoid.) Is there any current way to do this in PCB? If not, should I 
just ignore the remaining rat lines?

Thanks in advance,

Peter

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