Re: gEDA-user: Implicit or Explicit Power Pins

[John Doty <jpd@xxxxxxxxxxxxx>]

On Jun 5, 2006, at 5:28 AM, Stuart Brorson wrote:

> Here are possible things you can do:
>
> *  Redraw the symbol.  Yes, it's a PITA, but part of doing designs is
> drawing symbols.
>
> *  If the symbol has implied power pins (net= attribute), then just
> stick your decoupling cap on the same schematic sheet and attach it to
> your power net and GND.  To attach to the power net, just draw a net
> from the cap, and then give the net a netname= attribute.

Another way is to draw a separate symbol for the power and ground  
pins, and then give it the same refdes as the powerless symbol. Now  
you can have a perfectly explicit drawing of power distribution, but  
avoid cluttering the signal flow drawing with that stuff. This works  
for most gnetlist back ends, but unfortunately not for spice-sdb.

Stuart, can this be fixed? Your spice-sdb gives the obscure "Invalid  
wanted_pin passed to gnet-nets [unknown]" error when it sees a  
duplicate refdes. The reason I ask is that I'm retrofitting my chip  
design to have explicit power distribution (ah, the joy of changing  
customer requirements ;-).

John Doty              Noqsi Aerospace, Ltd.
jpd@xxxxxxxxxxxxx