MIDI Mule – A small MIDI foot controller

I was looking for a small MIDI foot controller to use with my Atomic AmpliFire which has only three foot switches.

Searching for a good solution I found a few Do-It-Yourself videos. One of them showcased a foot controller based on an Arduino Nano and this caught my attention. So I ordered an Arduino Nano and a few electronic components – switches, resistors, a DIN 5 jack, a DC power jack etc. and set up my first test environment.


Once it worked I ordered some momentary foot switches and thought about my own circuit board. I designed it using the open source tool “Fritzing” and sent the PDF-File to production.

Parts list

  • Arduino Nano
  • Circuit Board or perfboard
  • MIDI DIN 5 jack
  • DC power jack
  • 10 x 220 ohm resistor
  • Socket for the Arduino Nano
  • Bridge Rectifier (I used a Diotec B40R)
  • 8 x LED
  • 8 x Momentary foot switch
  • Wires

Everything arrived and I started assembling the foot controller. These images show the circuit board from the bottom and the top side. The bridge rectifier is there to protect the Arduino Nano from being fried. This happened to my first one when I accidently used a second power supply with an inverted polarity. I use a socket for the Arduino Nano just in case I have to replace it someday.

I decided to build the cover from some acrylic glass and Mahogany wood.

The software

This is my first version of the script. It uses the Arduino MIDI library by Forty Seven Effects and a Switch Debouncing library by Albert van Dalen. You’ll have to download the libraries and link them to your Arduino development environment.

MIDI Mule in action

I hope that this page helps you to design your own MIDI controller. If you find some errors or like to share your experience just contact me. These images show the original MIDI mule and a version I built into a pedal board..