Hardware

Hardware

To follow this guide you'll need the following parts:

Wiring

Connect your MCP230xx to your development board using a standard I2C connection.  Here's an example of wiring a MCP23017 to a Feather M0 board:

Remember you need to explicitly add pull-up resistors to the I2C SCL and SDA connections as shown above!

  • Board 3.3V output to MCP23017 Vdd
  • Board ground/GND to MCP23017 Vss
  • Board SCL to MCP23017 SCL
  • Board SDA to MCP23017 SDA
  • MCP23017 SCL to 4.7 kilo-ohm resistor connected to 3.3V
  • MCP23017 SDA to 4.7 kilo-ohm resistor connected to 3.3V
  • MCP23017 A0 to ground
  • MCP23017 A1 to ground
  • MCP23017 A2 to ground
  • MCP23017 reset to 3.3V

When in doubt consult the MCP23017 datasheet for exact details on its pins and wiring.

Here's an example of wiring a MCP23008 to a Feather M0 board:

Remember you need to explicitly add pull-up resistors to the I2C SCL and SDA connections as shown above!

  • Board 3.3V output to MCP23008 Vdd
  • Board ground/GND to MCP23008 Vss
  • Board SCL to MCP23008 SCL
  • Board SDA to MCP23008 SDA
  • MCP23008 SCL to 4.7 kilo-ohm resistor connected to 3.3V
  • MCP23008 SDA to 4.7 kilo-ohm resistor connected to 3.3V
  • MCP23008 A0 to ground
  • MCP23008 A1 to ground
  • MCP23008 A2 to ground
  • MCP23008 reset to 3.3V

When in doubt consult the MCP23008 datasheet for exact details on its pins and wiring.

This guide was first published on Mar 08, 2018. It was last updated on Sep 20, 2018. This page (Hardware) was last updated on Mar 08, 2018.