adafruit-circuitpython-pca9554

Introduction
============


.. image:: https://readthedocs.org/projects/adafruit-circuitpython-pca9554/badge/?version=latest
    :target: https://docs.circuitpython.org/projects/pca9554/en/latest/
    :alt: Documentation Status


.. image:: https://raw.githubusercontent.com/adafruit/Adafruit_CircuitPython_Bundle/main/badges/adafruit_discord.svg
    :target: https://adafru.it/discord
    :alt: Discord


.. image:: https://github.com/adafruit/Adafruit_CircuitPython_PCA9554/workflows/Build%20CI/badge.svg
    :target: https://github.com/adafruit/Adafruit_CircuitPython_PCA9554/actions
    :alt: Build Status


.. image:: https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json
    :target: https://github.com/astral-sh/ruff
    :alt: Code Style: Ruff

CircuitPython library for Adafruit PCA9554 GPIO expanders


Dependencies
=============
This driver depends on:

* `Adafruit CircuitPython <https://github.com/adafruit/circuitpython>`_
* `Bus Device <https://github.com/adafruit/Adafruit_CircuitPython_BusDevice>`_

Please ensure all dependencies are available on the CircuitPython filesystem.
This is easily achieved by downloading
`the Adafruit library and driver bundle <https://circuitpython.org/libraries>`_
or individual libraries can be installed using
`circup <https://github.com/adafruit/circup>`_.

* Adafruit Qualia ESP32-S3 for TTL RGB-666 Displays

`Purchase one from the Adafruit shop <http://www.adafruit.com/products/5800>`_

Installing from PyPI
=====================
On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally `from
PyPI <https://pypi.org/project/adafruit-circuitpython-pca9554/>`_.
To install for current user:

.. code-block:: shell

    pip3 install adafruit-circuitpython-pca9554

To install system-wide (this may be required in some cases):

.. code-block:: shell

    sudo pip3 install adafruit-circuitpython-pca9554

To install in a virtual environment in your current project:

.. code-block:: shell

    mkdir project-name && cd project-name
    python3 -m venv .venv
    source .env/bin/activate
    pip3 install adafruit-circuitpython-pca9554

Installing to a Connected CircuitPython Device with Circup
==========================================================

Make sure that you have ``circup`` installed in your Python environment.
Install it with the following command if necessary:

.. code-block:: shell

    pip3 install circup

With ``circup`` installed and your CircuitPython device connected use the
following command to install:

.. code-block:: shell

    circup install adafruit_pca9554

Or the following command to update an existing version:

.. code-block:: shell

    circup update

Usage Example
=============

.. code-block:: python

    import time
    import board
    import digitalio
    import adafruit_pca9554

    board.I2C().deinit()
    i2c = board.I2C()
    tft_io_expander = dict(board.TFT_IO_EXPANDER)

    pcf = adafruit_pca9554.PCA9554(i2c, address=tft_io_expander['i2c_address'])
    button_up = pcf.get_pin(board.BTN_UP)
    button_up.switch_to_input(pull=digitalio.Pull.UP)

    while True:
        print(button_up.value)
        time.sleep(0.01)  # debounce

Documentation
=============
API documentation for this library can be found on `Read the Docs <https://docs.circuitpython.org/projects/pca9554/en/latest/>`_.

For information on building library documentation, please check out
`this guide <https://learn.adafruit.com/creating-and-sharing-a-circuitpython-library/sharing-our-docs-on-readthedocs#sphinx-5-1>`_.

Contributing
============

Contributions are welcome! Please read our `Code of Conduct
<https://github.com/adafruit/Adafruit_CircuitPython_PCA9554/blob/HEAD/CODE_OF_CONDUCT.md>`_
before contributing to help this project stay welcoming.