kicad-developers team mailing list archive

[Oscad Team <oscad.team@xxxxxxxxx>]

Hello All

Thanks for your inputs. We identified the reason why we did not get the
expected outputs in Ngspice. It was not because of having net names in the
netlist. And we have decided to go for netlists with net names instead of
net numbers, as it is more user friendly.

Thanks
Oscad Team


On Fri, Jun 27, 2014 at 9:17 PM, Rick Walker <walker@xxxxxxxxxxxxxx> wrote:

>
> Hello Oscad team,
>
> > We wanted netlist with netnumbers to simulate the circuit using Ngspice.
> > Ngspice is not able to recognize the netlist with netnames.
>
> I don't believe that is the case.  Ngspice allows arbitrary
> identifiers for node names.  For example, this subckt runs fine
> under the current ngspice release:
>
>     *********************************************
>     * transmission line model with skin loss
>
>     .subckt skinline in 0 out 0 z0=50 length=1 rdc=1 lint=1n
>     * hybrid sections at each end
>     x1 in x1in x1out x1eqout x1eqin thyb
>     x2 out x2in x2out x2eqout x2eqin thyb
>
>     * equalization circuits
>     x3 x1eqout x1eqin 0 skin6 length={length} rdc={rdc} lint={lint}
>     x4 x2eqout x2eqin 0 skin6 length={length} rdc={rdc} lint={lint}
>
>     * ballistic delay modelling
>     t1 x1out 0 x2in 0 td={length*lint/z0} Z0={z0}
>     t2 x2out 0 x1in 0 td={length*lint/z0} Z0={z0}
>     .ends skinline
>     *********************************************
>
> Notice the use of names like "x1equout" and "x2in" to make it easy to
> post process the nodes without using a graphical system.
>
> I expect that the Oscad backend has some kind of historical limitation
> to use integers for net names.  This is not a limitation with Ngspice.
>
> I suggest that kicad use the node names that the user gives them.
> Any unnamed nets can be arbitrarily assigned sequential names
> like "node99" or just "99".  Please do not override the explicit
> names given in the schematic.
>
> If the Oscad tools do not currently accept arbitrary ASCII strings for
> node names, this should be fixed with a high priority.  If the Oscad
> internal bookkeeping requires integers for node numbers, then what is
> needed is a simple symbol table to convert each incoming identifier to
> an internal node number.
>
> It will be very awkward if the end user cannot use symbolic node
> names.  This would break just about every modern tool flow that I know
> of.
>
> kind regards,
> --
> Rick Walker
>
>
>