This is (my) perfect directory for embedded C projects. It is loosely base on The Pitchfork Layout (PFL) which is a convention for laying out source, build, and resource files widely accepted by the C/C++ community. It is designed to provide a clear and organized structure for the project, making it easier to maintain and debug.
The original PFL describes 11 top-level directories. Depending on the simplicity of the project, you can consider some of them non-essential like data/ or examples/. So feel free to skip them depending on your needs. I've added bin/ which contains the binary files for a specific architecture.
bin/
build/
src/
external/
docs/
tools/
tests/
data/
examples/
extras/
The PFL structure originally defines a include/ folder to to hold all the public API headers. However I prefer to keep the source and header files in the same directory for ease of navigation.
Example:
<root>/
├─ src/
└─ cat/
└─ sounds/
├─ hiss.h
└─ hiss.c
Holds executable scripts and binaries that are run in order to use the project. These files are typically compiled from the source code in the src folder, or from third-party libraries in the external folder.
Contains generated files that are produced when running build scripts. These files are compiled from the source code and can be used to create a final product. Here you can also place the project abd workspace files associated to your IDE. Example: .eww and .ewp for IAR Embedded Workbench or .ioc and .mxproject for STM32CubeIDE.
Holds all the source code for the project including the main program and any modules or components. It is typically organized into sub-folders.
Stores third-party libraries that are used in the project. Each library should occupy a single subdirectory of external/.
Subdirectories of external/ should not be modified as part of regular project development. Subdirectories should remain as close to their upstream source as possible.
Example: HAL libraries provided by the silicon vendor, and RTOS.
Contains documentation for the project and explains how the project works and how to use it.
The tools folder holds scripts and other tools that are used in the project and are useful for automating certain tasks.
Holds the test sources that are used to ensure that the project is functioning correctly. You should provide a way to disable the compilation and running of tests, especially for the purpose of embedding.
It is designated for holding project files which should be included in revision control, but are not explicitly code.
Example: graphics and localization files are not code in the same sense as the rest of the project, but are good candidates for inclusion in the data/ directory.
It is reserved for source files related to example and sample usage of the project that can be used as a point of reference for developers.
Finally, the extras folder contains any miscellaneous files related to the project.