Installation¶

MicroPythonMCU runs on 64-bit Windows with OpenModelica (OMEdit, tested with versions 1.24.4, 1.26.8 and 1.27.1). The Python runtime ships with the library and the C compiler is OpenModelica's own: nothing else to install, apart from the Microsoft Visual C++ Redistributable, which is almost always already present.

Choosing a version¶

Each version of the library is a tag of the repository, of the form vX.Y.Z (for example v0.1.0). The list of versions is on the tags page. Take the most recent one unless you have a reason not to.

Downloading a version¶

1. On the tags page, click the download button (arrow) of the version you want, then zip. Direct address, for v0.1.0:

   https://gitlab.com/bdelaup/modelica_micropython3/-/archive/v0.1.0/modelica_micropython3-v0.1.0.zip
   

   With git: git clone --branch v0.1.0 https://gitlab.com/bdelaup/modelica_micropython3.git

2. Unzip it, preferably outside a synchronised folder such as OneDrive. It contains the MicroPythonMCU folder, which is the library itself (it holds package.mo).

   No accented characters in the path

   The full path of the folder must not contain any accented character (é, è, à…): otherwise compilation fails with fatal error: 'PyRuntimeImpl.c' file not found. This is a limitation of OpenModelica's compilation toolchain on Windows. For instance, C:\Users\<name>\Downloads\Téléchargements\… fails, while C:\Users\<name>\Documents\modelica\… works. Spaces are fine.

Load or install¶

There is no need to install the library: loading it in OMEdit is enough. Three ways, from the lightest to the most lasting.

Load the library, without installing anything¶

In OMEdit, File → Open Model/Library File(s)…, then select MicroPythonMCU/package.mo. The library appears in the browser for the session: to be repeated each time OMEdit starts. In a script: loadFile("C:/path/to/MicroPythonMCU/package.mo");.

This is the recommended way to try a version, or to work on a shared computer: nothing is copied outside the downloaded folder, and several versions can live side by side in different folders.

Load it automatically at each start¶

To avoid reopening the file each time, still without installing: Tools → Options → Libraries, User Libraries section, add the path of MicroPythonMCU/package.mo. OMEdit then loads it at every start, from the downloaded folder.

Install it as a system library¶

The library then joins OpenModelica's libraries and is loaded on demand:

1. Close OMEdit.

2. Copy the MicroPythonMCU folder into the user's OpenModelica library folder:

   %APPDATA%\.openmodelica\libraries\
   

3. Reopen OMEdit, then File → System Libraries → MicroPythonMCU. In a script: loadModel(MicroPythonMCU);.

To switch versions, replace this folder with the one from another version.

Checking¶

Open MicroPythonMCU.Examples.BasicBlink and simulate it: GP0 blinks (see Getting started).

The first simulation of a model takes longer (from one to a few tens of seconds more): OpenModelica compiles the library's C runtime with its own compiler, from the supplied sources. This is normal, and it is what makes any recent OpenModelica version usable.

Coming soon: installation through the library manager¶

Registration of the library in OpenModelica's package index is under way. Once done, nothing will need downloading: in OMEdit, File → Manage Libraries → Install Library, or in a script installPackage(MicroPythonMCU);. Each tag will become an installable version.

Development version¶

To try the current state between two versions: clone the repository without specifying a tag, or download it (Code → zip), then proceed as above.