PCF8574 library. i2c digital expander for Arduino, Raspberry Pi Pico and rp2040 boards, esp32, SMT32 and ESP8266. Can read write digital values with only 2 wire. Very simple to use and encoder support ...
A reimplementation of the standard Arduino LCD library, configured to work with parallel HD44780 compatible LCDs, and interfaced via a Chinese PCF8574 I2C serial extender.