PiPCA9685

PiPCA9685 provides an interface for controlling a PCA9685 chip from a Raspberry Pi in C++ and Python.

This library was originally designed to control servos with Adafruit's PWM Hat. It was born out of a desire for C++ bindings, which Adafruit did not provide.

Installation

1. Before you begin, make sure your Pi has I2C enabled.

   This step is not needed when using Ubuntu.

   1. Run sudo raspi-config
   2. Select "Interfacing Options"
   3. Enable I2C automatic loading

2. Clone repo

   git clone https://github.com/barulicm/PiPCA9685.git

3. Install dependencies from apt

   cd PiPCA9685
   xargs -a apt_dependencies.txt sudo apt-get install -y

   Note: On Ubuntu, you may need to enable the universe repostiory with the command below to find some of the needed packages. This is NOT needed on Raspberry Pi OS.

   sudo add-apt-repository universe

4. Build and install library

   sudo cmake --workflow --preset install

   Alternatively, you can install the library without root permissions, only for your user, with the following command:

   cmake --workflow --preset install-nonroot

Uninstalling

You can uninstall the library with this CMake command:

sudo cmake --workflow --preset uninstall

Or, if you installed without root permissions, use this command:

sudo cmake --workflow --preset uninstall-nonroot

Examples

You can find simple examples of how to use this library in C++ and Python in the examples directory.

C++

To build and run the C++ example, run the following commands in the examples/cpp/ directory.

cmake --workflow --preset build
./build/example-cpp

If you installed without root permissions, you may need to tell cmake where to find the library:

PiPCA9685_DIR=~/.local/lib/cmake/PiPCA9685/ cmake --workflow --preset build
./build/example-cpp

Python

To run the Python example, run the following command in the examples/python/ directory.

python3 example.py