Adafruit PCF8575 I2C 16 GPIO Expander Breakout - STEMMA QT / Qwiic

Expand your project possibilities, with the Adafruit PCF8575 GPIO Expander Breakout - an affordable 16 channel I2C expander.GPIO expanders work like this: you have a board with some number of GPIO but not enough for your project - maybe you need more buttons or LEDs. You could upgrade to a board with massive number of GPIO like the Grand Central, or you could pop on one of these boards. Connect it over I2C and then you can send/receive I2C commands to control the GPIO pins to write and read them. It's going to be slower than direct GPIO access, but maybe that doesn't matter if it takes a millisecond instead of a microsecond. You only need the two I2C pins, and you can even share the I2C port with other sensors and devices. Heck, you can even add more expanders for massive I/O control!The PCF8575 is a common and slightly unusual I2C expander for folks who are used to the MCP230xx series: First up, it's very affordable - who doesn't love that? It has 16 I/O pins Three I2C address select