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Functional Mock-up Interface

The Functional Mock-up Interface (FMI) is a free standard that defines an interface to exchange dynamic models using a combination of XML files, binaries and C code. It’s supported by 170+ tools and maintained as a Modelica Association Project.

Releases and the latest development version of the specification are available on the FMI website.

Repository Structure

  • docs — sources of the specification document

  • headers — header files of the C-API

  • schema — XSD schema for the modelDescription.xml

  • CONTRIBUTING.adoc — info on contributing to the project and building the specification document

  • README.adoc — this document


  • main — development of the next release

  • v{2|3}.0.x — maintenance of the 2.0 and 3.0 releases

Layered Standards

The following layered standards are currently under development.

  • XCP — information for calibration and measurement

  • Network Communication — mapping of variables to buses

  • Structure — semantic grouping of variables

Code and documentation copyright © 2008-2011 the MODELISAR consortium and 2012-2024 the Modelica Association Project FMI. Code released under the 2-Clause BSD License. Docs released under Attribution-ShareAlike 4.0 International.