AVR C/C++ Project Template (CMake)

Flexible bare-metal development template for the AVR microcontroller family (ATmega, ATtiny, etc.). Built with CMake. seamlessly supports standalone or mixed C and C++ development workflows.

Configured out-of-the-box for the ATmega328P, it can easily target any AVR chip by passing configuration variables during CMake setup.

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Table of content 📋

1. Directory Structure
2. Prerequisites
3. Quick Starts
4. Configuration Options
5. Library
6. Editor Integrations
7. ToDo List
8. License

Directory Structure 📂

├── .clangd                         # Clangd configuration for code completion and analysis
├── .vscode/                        # VS Code configuration directory
├── .zed/                           # Zed editor configuration directory
├── cmake/
│   └── avr-gcc.toolchain.cmake     # AVR cross-compilation toolchain file
├── include/                        # Public header files (.h / .hpp)
├── lib/                            # Local libraries and reusable components
├── src/                            # Application source code (.c / .cpp)
│   └── main.cpp                    # Application entry point (or main.c)
├── CMakeLists.txt                  # Main CMake configuration file
└── README.md                       # Project documentation

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Prerequisites❗

Ensure the following tools are installed on your host system and available in your system PATH:

• AVR Toolchain: Microchip AVR Toolchain
• Programmer Utility: AVRDUDE.
• Build System: CMake (v3.16+) and a build generator like Ninja or GNU [Make].

1. Windows (Recommended: use MSYS2 UCRT64)

Open the MSYS2 UCRT64 terminal and run:

pacman -S --needed mingw-w64-ucrt-x86_64-avr-toolchain mingw-w64-ucrt-x86_64-avrdude mingw-w64-ucrt-x86_64-cmake mingw-w64-ucrt-x86_64-ninja mingw-w64-ucrt-x86_64-make

Note: Ensure C:\msys64\ucrt64\bin is added to your Windows system PATH if invoking these commands outside the MSYS2 terminal.

2. Linux (Debian / Ubuntu)

Run the following command in your terminal:

sudo apt update && sudo apt install -y gcc-avr binutils-avr avr-libc avrdude cmake ninja-build make

3. macOS (Homebrew)

Run the following command in your terminal:

brew install avr-gcc avrdude cmake ninja

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Quick Starts🛠️

1. Clone the Repo

Clone the repository and navigate to the project directory:

git clone https://github.com/Arif-Rachmat/AVR-CMake-Template.git <YOUR_PROJECT_DIR>
cd <YOUR_PROJECT_DIR>

2. Configure the Project

Standard Configuration (Default: ATmega328P @ 16MHz):

cmake -B build -DCMAKE_TOOLCHAIN_FILE=cmake/avr-gcc.toolchain.cmake

Targeting a Different MCU (e.g., ATtiny85 @ 8MHz via USBasp):

cmake -B build \
  -DCMAKE_TOOLCHAIN_FILE=cmake/avr-gcc.toolchain.cmake \
  -DMCU=attiny85 \
  -DF_CPU=8000000UL \
  -DAVRDUDE_PROGRAMMER=usbasp \
  -DAVRDUDE_PORT=usb

3. Compile Firmware

Build the executable (.elf), binary (.hex), and output memory usage:

cmake --build build

4. Flash Microcontroller

Upload the firmware to hardware using avrdude:

cmake --build build --target flash

Cleaning Build Directory

Delete all compiled objects and generated output files:

cmake --build build --target clean
# Or simply remove the build folder: rm -rf build/

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Configuration Options ⚙️

Default parameters target the ATmega328P (e.g., Arduino Uno/Nano). You can override them inside CMakeLists.txt or pass them via -D flags during configuration:

Option	Default Value	Description	Examples
MCU	atmega328p	Target microcontroller architecture.	attiny85, atmega2560, atmega32u4
F_CPU	16000000UL	Clock frequency in Hz.	8000000UL, 1000000UL
AVRDUDE_PROGRAMMER	arduino	Programmer hardware driver.	usbasp, wiring, avrispmkii, serialupdi
AVRDUDE_PORT	COM5	Upload serial port.	COM3, /dev/ttyUSB0, /dev/ttyACM0

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Library 📚

This template supports integrating reusable libraries through the lib/ directory. Each library can be kept self-contained with its own source files, headers, and CMake configuration, or following the exact directory structure of this template . while the main project handles adding and linking it to the application.

A minimal workflow looks like this:

lib/
└── my_library/
    ├── include/
    │   └── my_library.h
    ├── src/
    │   └── my_library.c
    └── CMakeLists.txt

Make sure the CMakeLists of the library expose the header and add the source as static library:

add_library(${PROJECT_NAME} STATIC ${SOURCES})
target_include_directories(${PROJECT_NAME}
   PUBLIC
      include
)

Or if using this template to build the library, simply set the AVR_PROJECT_TYPE variable at the top of CMakeLists.txt to LIBRARY:

set(AVR_PROJECT_TYPE LIBRARY) 

The application can then use the library normally:

#include <my_library.h>

int main()
{
    my_library_init();
}

This keeps reusable code separated from application-specific code while allowing everything to be built together as a single firmware project.

For more information about library and building one go to the lib README page.

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Editor Integration 🔗

Visual Studio Code (see VSCode folder)

1. Install the C/C++ (ms-vscode.cpptools) and CMake Tools (ms-vscode.cmake-tools) extensions.
2. Run CMake: Configure from the Command Palette (Ctrl+Shift+P / Cmd+Shift+P).
3. Build using F7 and flash via the CMake side-bar target menu.

Zed (see Zed folder)

1. Open the project folder in Zed.
2. Run the setup task:
   • Open command palette (Ctrl+Shift+P / Cmd+Shift+P) and type task: spawn.
   • Select CMake: Configure (AVR Toolchain).
3. Compile or flash the target:
   • Select CMake: Build Firmware to compile.
   • Select AVR: Upload / Flash Firmware to flash.
4. Code completion and register navigation (<avr/io.h>) are handled natively via clangd.

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To-Do List 📌

• Add more built in editor support/configurations.
• Add libraries repository links as the example of directly pulling and integrating a library.
• Expand chip target presets and MCU frequency configurations in CMakeLists.txt.
• Add documentation for custom avrdude programmer types and baud rates.

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License 📜

This project is licensed under the MIT License — free for both personal and commercial use.