Re: gEDA-user: GND=VSS

[Ales Hvezda <ahvezda@seul.org>]

Hi,

>I want VSS be the same as GND. I made a piece of net in gschem, connected
>it to the ground, named VSS and nothing happened. Then I removed this and
>renamed some other existing net that connected some capacitor to GND with
>name VSS and it works however:


	This is a bug in gnetlist.  I have filed bug#109 to address this.



>1) why it works for one piece of net and not another?
>2) I get this warning message from gsch2pcb:
>Found duplicate net name, renaming [GND] to [VSS]
>WARNING: Trying to rename something twice:
>        GND and GND
>are both a src and dest name
>This warning is okay if you have multiple levels of hierarchy!
>3) The resulting net in the *.net file is called VSS and I like GND more.
>Can I change this somehow how it will be called (not using sed, please)?
>


	There is a workaround, well actually more of a *gross hack*,
it is not pretty and I really do not recommend it, *especially* if you use
the other gnd/vcc symbols in conjunction to named nets (since gnd/vcc
will be renamed to the specified net).

Basically, create a symbol like this (maybe called rename-1.sym):

v 20040111 1
P 200 200 200 400 1 0 1
{
T 300 300 5 6 0 0 0 0 1
pinnumber=1
T 300 200 5 6 0 0 0 0 1
pinseq=1
}
L 100 100 200 200 3 0 0 0 -1 -1
L 200 200 300 100 3 0 0 0 -1 -1
T 200 100 5 6 1 1 0 5 1
device=rename

and attach this to the other end of your "piece of net with the vss symbol".
Also you need to put the following in a gnetlistrc file:

(net-naming-priority "netname")

Now, when you run gnetlist you will get an warning/error message like this:

Could not find refdes on component and could not find any special attributes!

which is refering to the rename-1.sym.

Now your netlist will have the properly renamed Vss -> GND net.  I don't
know if this will work with gsch2pcb.

Again, don't use this hack unless you are very comfortable with the
dire consequences/side effects of (net-naming-priority "netname").
I need to fix this properly, so you may want to wait for the real fix.
I'm really quite surprised that nobody has run across this previously.

								-Ales