How to connect the MCP21017 GPIO Expander to an Arduino and Raspberry Pi

In this episode, we take a look at the MCP23017 GPIO Expander IC. With this IC, we can add 16 GPIO pins to the existing GPIO pins on an Arduino, Raspberry Pi, or any micro controller that has an i2c bus. They can be “stacked” for up to 128 additional GPIO pins! Bring on the LED’s!