gEDA-user: spice-sdb sets ground as different nodes.

[Allan Espinosa <yecartes@xxxxxxxxx>]

I started using geda-gschem+gnetlist-20050329 version and tried to
create an audio ampifier with an LM386 model from the net.  When I run
gnetlist -g spice-sdb audio.sch, it says that there is no pin
description list.  Judging from the output.net file, I say that an IC
(U) is being generated from the schematic which I don't have.  To
simplify and isolate the problem, I created a voltage divider
schematic as follows

--foo.sch--
v 20050313 1
C 36400 74700 1 0 0 resistor-1.sym
{
T 36600 75000 5 10 1 1 0 0 1
refdes=R1
T 36400 74700 5 10 0 0 0 0 1
value=220
}
C 37500 74700 1 0 0 resistor-1.sym
{
T 37700 75000 5 10 1 1 0 0 1
refdes=R2
T 37500 74700 5 10 0 0 0 0 1
value=220
}
N 37300 74800 37500 74800 4
{
T 37300 74800 5 10 0 0 0 0 1
netname=Vout
}
C 35700 73300 1 0 0 vdc-1.sym
{
T 36400 73950 5 10 1 1 0 0 1
refdes=Vin
T 36400 73750 5 10 1 1 0 0 1
value=DC 10V
}
N 36000 74500 36000 74800 4
N 36000 74800 36400 74800 4
{
T 36000 74800 5 10 0 0 0 0 1
netname=Vin
}
C 38400 74100 1 0 0 ground.sym
C 35800 72800 1 0 0 ground.sym
N 36000 73100 36000 73300 4
N 38600 74400 38600 74800 4
N 38600 74800 38400 74800 4
--end foo.sch--

Here is the output of gnetlist -v -g spice-sdb foo.sch:
--gnetlist verbose logging--

Missing Attributes (refdes and pin number)
Missing Attributes (refdes and pin number)
Could not find refdes on component and could not find any special attributes!
Missing Attributes (refdes and pin number)
Could not find refdes on component and could not find any special attributes!
Missing Attributes (refdes and pin number)
Using SPICE backend by SDB -- Version of 10.9.2004
schematic-type = normal schematic
Command line passed = gnetlist -g spice-sdb foo.sch
Loading schematic [/home/allan/tmp/foo.sch]
--end verbose logging--

As you can see in the netlist, there is a U component being generated.
--output.net--
* gnetlist -g spice-sdb foo.sch
*********************************************************
* Spice file generated by gnetlist                      *
* spice-sdb version 10.9.2004 by SDB --                 *
* provides advanced spice netlisting capability.        *
* Documentation at http://www.brorson.com/gEDA/SPICE/   *
*********************************************************
R2 Vout 1 220
R1 Vin Vout 220
U? unknown
Vin Vin 2 DC 10V
.END
--end netlist--

Nodes 1 and 2 should be set to zero.  I tried running gnetlist on the
the sample packages in http://www.brorson.com/gEDA/SPICE/ ( I think it
was the TwoStageAmp) and the ground node was resolved properly.

Where is the U? component coming from? I don't remember placing any
symbol other than resistors, ground and voltage sources.  And why does
it treat the ground nodes differently?  In my audio amplifier ground
was not being noded properly but voltage sources/ netnames like Vss
get properly resolved.

--
Allan M. Espinosa
http://www.freepgs.com/yecartes/wiki.pl