Re: gEDA-user: DRC vs shorted nets?

[Bob Paddock <bpaddock@csonline.net>]

On Saturday 01 May 2004 02:25 pm, harry eaton wrote:

> > 3: WARNING!! net "P3V3" is shorted to net "GND"
> > 4: WARNING!! net "GND" is shorted to net "P3V3"
>
> In the future it is good to request a rat's nest at the end of the design
> (rather than rely on it being a mistake) in order to verify the 
> connectivity. 

> Netlist shorts  are NOT DRC errors. 

I expected the error to be a DRC because the optimizer moved traces, and the
error was not there prior to moving traces.  The connectivity of the traces 
did not change, only their location.

> There are connectivity errors which are checked by the rats nest function. 

Why do these connectivity errors  only show up when the design is completed?  
At that point there are no rats.  Should such short not show up all of the 
time?

> > I've noticed that I get odd shorts after doing Othropull's but usually
>
>
> People need to submit example layout to the bug tracker at sourceforge

There is an example there now.

> My feeling right now is that the optimizer is a dangerous

There have been a  couple of times that I'm sure I saved a clean design, but 
on reloading it it had errors.  I've not figured out a reproducible sequence.
So I'm only 90% sure that what I'm seeing is optimizer related in some cases.
The error is always the one of connectivity.

-- 
                    http://www.softwaresafety.net/
       http://www.unusualresearch.com/ http://www.bpaddock.com/