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.

Last updated on Mar 08, 2018 Published on Mar 08, 2018