Gnucap source code is organised as a main library with plugins developped in numerous git repositories. Plugins and extensions not shipped with the main “Gnucap” package require a Gnucap installation for compilation and use. Installation instructions can be found in the INSTALL file at the top level of the source repository, and in the respective documentation of the extension packages. Beware of out-of-date binary packages distributed elsewhere. When building from source, make sure to match version tags across repositories, or use the current develop branches.

Gnucap is undergoing developments that add support for Verilog-AMS, towards providing a contemporary approach to circuit simulation. Right now, normal use can involve old stuff, and some of the official examples involve antiquated syntax. To get unstuck, focus on examples involving Verilog features.

There are input files in the main package that we use for testing. Older ones, “*.ckt” resemble batch files from the Spice2 era, and may be executed with “gnucap -b”. Newer ones, with ”.gc” extension can be read directly, i.e. without ”-b” flag. Not all tests are instructive or beginner friendly…

In addition to tests, modelgen-verilog has examples with instructions, too. The vams library implements example “SPICE primitives” from Annex E in Verilog-AMS.

Examples from the Qucs project demonstrate data interchange with a schematic editor.

The models-repo contains example uses of devices with SPICE interface.

There are themed examples in various other repos such as here and here.