Adafruit PCF8574 
This is the Adafruit PCF8574 I2C GPIO Exapnder library
Tested and works great with the Adafruit PCF8574 Breakout Board
This chip uses I2C to communicate, 2 pins are required to interface
Adafruit invests time and resources providing this open source code, please support Adafruit and open-source hardware by purchasing products from Adafruit!
Dependencies
Contributing
Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.
Documentation and doxygen
Documentation is produced by doxygen. Contributions should include documentation for any new code added.
Some examples of how to use doxygen can be found in these guide pages:
https://learn.adafruit.com/the-well-automated-arduino-library/doxygen
https://learn.adafruit.com/the-well-automated-arduino-library/doxygen-tips
Written by ladyada for Adafruit Industries. BSD license, check license.txt for more information All text above must be included in any redistribution
To install, use the Arduino Library Manager and search for "Adafruit PCF8574" and install the library.