Mail Archives: geda-user/2015/09/11/13:50:05
On Sep 11, 2015, at 11:07 AM, DJ Delorie <dj AT delorie DOT com> wrote:
>
>> It could be a lot easier to add copper spacing rules in the
>> schematic. I guess attaching spacing attribute to nets possible
>> refering to a specific category for example "InverterOutputVoltage"
>> may solve it in the schematic but it must also be transferred to the
>> layout.
>
> Sure, attaching text to objects is easy if the application doesn't
> need to understand the text. gschem doesn't impose any copper spacing
> rules on schematics, so it doesn't care what text you add relating to
> copper spacing rules. It's just text.
>
> PCB has to enforce the rules, so it needs to both understand the
> desired rules and know how to impose them on the design. That's a
> much harder task than just keeping track of some text.
We have DRC for geda-gaf appropriate for its function. Somewhat configurable for the application, and the user can use judgement as to what to pay attention to. Its model of what the user is doing is restricted, but since it doesn’t actually enforce anything that’s annoying but harmless. If anyone wants to fix the annoyances they can write a new script. This avoids the “one man’s bug is another’s feature” problem. But the user need not rewrite and maintain gnetlist, just one script, or perhaps part of one. Simply overriding some internal function with an add-on is sometimes sufficient when a “standard” gnetlist script needs a little help.
I found gnet-spice and gnet-spice-sdb inadequate for my purposes, so I wrote gnet-spice-noqsi. That limits nobody and does not interfere with any existing flow. I am interested in liberation, not control.
>
> I'm not denigrating the usefulness of being able to put arbitrary text
> anywhere; we added that to pcb (somewhat) as well. But don't think
> that being able to add a chunk of text is the same as doing something
> useful with that text.
>
Having the text is a prerequisite. If you don’t have it, you can’t do anything with it. Liberty does not get jobs done, but it gets out of the way.
“100% of shots not taken don’t go in.” -Wayne Gretzky
John Doty Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd AT noqsi DOT com
- Raw text -