PCF8574 Arduino Library.
PCF8574/PCF8574A - Remote 8-bit I/O expander for I2C-bus with interrupt. Example usage: The LCM2004A liquid crystal display module (HD44780U device) interfaced for I2C with a PCF8574. Device datasheet: https://www.nxp.com/docs/en/data-sheet/PCF8574_PCF8574A.pdf
Maintainer: Jean-Marc Paratte
This library is compatible with all architectures so you should be able to use it on all the Arduino boards.
To use this library, open the Library Manager in the Arduino IDE and install it from there.