l4u / kicad_component_layout

Scripted component layout plugin for KiCad/pcbnew

Kicad Component Layout Plugin

A python plugin for KiCad to assist with script driven component layout.

How to install

The component_layout_plugin.py file needs to be located into the KiCad script search path. For example, on linux, it could go in ~/.kicad/scripting. In python 6.0.1 (and later?) you can go to Tools->External Plugins->Open Plugins Directory to find the location. Once there, the script should be available to run in KiCad under 'Tools -> External Pluging', or using the button on the toolbar.

For Windows:

The Windows version of KiCad packages its own internal copy of Python 2.7. To install the required YAML dependency, open a command prompt as administrator and type:

"C:\Program Files\KiCad\bin\python.exe" -m pip install pyyaml==5.2

How to use

When run in pcbnew, the plugin reads information about how to position components on the board from the file layout.yaml located in the project directory. The data in layout yaml allows the plugin to change the layer (top/bottom), position, rotation, and footprint for the given module.

An example layout.yaml file:

    origin: [x0, y0] # Offset applied to all component locations
    components:
        R1:
            location: [x, y] # mm
            rotation: r # degrees (float)
            flipped: false
            footprint:
                path: path/to/library.pretty
                name: SomeFootprint
        J1:
            ...

All the fields are optional for each component (e.g. leave footprint unspecified to leave the footprint unchanged).

The footprint path is relative to the directory containing the KiCad PCB file.

Typically, I will then create a python script to generate the layout.yaml based on the needs of the design.

The components must be instantiated in the schematic first.

Caveats

1. The schematic has to assign a footprint, so if you override the footprint in layout.yaml, the plugin will have to be run again after importing changes from schematic in order to restore the footprint.
2. You have to check the "Re-associate footprints by refdes" option when performing the update from schematic. If you don't, it will delete and recreate all the components with the footprints in the schematic. You can simply run the plugin again to fix them.
3. This works with KiCad 5.1.9, and with KiCad 6.0.4 -- see below for 6.0.1, and 6.0.2. It may stop working on a future version.
4. Make sure you do not have any components selected when you run the layout plugin. If your layout file changes footprints while components are selected, this causes KiCad to crash -- this appears to no longer be an issue in KiCad 6.x.

Known issue with 6.0.1, 6.0.2

This script is updated to work with KiCad 6.0.1. There were some changes, and if you have an old version it will not work -- likely you get will an error about missing the 'FindModuleByReference` function. However, there is an unresolved issue that causes KiCad to segfault on exit after the script is run. This doesn't prevent the script from working, and as far as I can tell, KiCad continues to run correctly after running the script until you exit. See this issue.

This was resolved in 6.0.3.