[Gnucap-devel] Fwd: Re: [Qucs-devel] Status update / request for feedback / questions (AMS)

[Richard Crozier]

Forwarding this from our list, in case anyone is interested.

Richard


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-------- Original Message --------
Subject: Re: [Qucs-devel] Status update / request for feedback / 
questions (AMS)
Date: Wed, 28 Aug 2013 00:36:04 -0700
From: Kevin Cameron <address@hidden>
To: Richard Crozier <address@hidden>
CC: address@hidden


Just FYI I did an integration of Icarus Verilog with GNUcap and another 
with Spice3 for mixed signal with Icarus being loaded as a shared library -

http://iverilog.wikia.com/wiki/GIT_Branch_Summary - embedded-vvp (the 
bulk of the code, C++)

For GNUcap/Spice I just modified the PWL sources to call out to the 
dynamically loaded code for data points, and for Icarus I added VPI code 
to locate the (non-blocking) assignments and convert them to PWL data. I 
added truncation code in the PWL sources to catch the logic thresholds 
on A->D boundary. Control gets handed to the subordinate simulators 
between solving and final acceptance (as far as I can remember).

Can probably get it working again if anyone is interested.

Kev.


On 08/27/2013 02:34 AM, Richard Crozier wrote:
> On 26/08/2013 19:29, Soeren D. Schulze wrote:
> > Hi again,
> >
> >
> > * e_trsolver was temporarily disabled.  What exactly does it do?
> e_trsolver is the nascent external interface (external trsolver) I am
> creating to the qucs transient solvers. It provides a means to interact
> with the solver between each time step, or even completely control the
> stepping from another program when qucs is compiled as a library (which
> has to be done manually at the moment).
>
> The external interface currently works in two ways, synchonous or
> asynchronous. In the asynchonous version it is intended that two time
> steps will be provided and the qucs solvers solve between these as they
> normally do, choosing their own minor time steps and simply reporting
> the values of the solution at the end. In the synchronous version
> however it is intended that all step control is performed by the
> external program, using the previous solution values reported by qucs. I
> have a prototype of this working using the Matlab/Octave solvers, which
> determine the local gradient by fitting a 3-point spline to the previous
> solution values. This is crude but seems to work ok for testing.
>
> Richard