In my last tutorial, I talked about the TCA9548A MUX which can be used to add at the max of 64 I2C or I²C sensors to your Arduino/ESP8266/ESP32. In this tutorial, I am going to talk about the PCF8574 8-bit GPIO Port Extender. It is one of the many GPIO extenders available in the market.This tiny lit…By: Tarantula3 // Read more: original article.