Arduino MIDI pedal for LINE6 HX Stomp

This repo contains source code for an Arduino sketch that emulates 4 foot switches of LINE 6 HX Stomp via MIDI interface.

What is this good for?

HX stomp is a great device for me though, it has only 3 footswitches(FS) so the control is quite limited. To use more FS you can plug in some 2-switch box to EXP/FS socket but if you're using this port for an expression pedal than have no luck. So the solution is using built-in MIDI interface and Arduino. You know, we are MAKERS :)

HW Parts

• 1 x Arduino
  • Tested with Arduino UNO. Others with same spec. should work
• 4 x momentary switches
  • Bring your favorite pedal switches (any momentary on/off switch works)
• 2 x LEDs of your choice
  • Optional. One for power, the other indicates activation status
• 1 x 5-PIN DIN female MIDI socket
  • Good old MIDI interface socket
• 2 x 220 ohm resistors
  • These two resistors are required to connect MIDI socket to Arduino

Circuit

• MIDI Socket
  • Arduino Pin 1(Tx) to Pin 5 of MIDI socket through 220ohm resistor
  • Arduino GND to Pin 2 of MIDI socket
  • Arduino + 5V to pin 4 of MIDI socket through 220ohm resistor
• Switches
  • Arduino Pin 2, 3, 4, 5 to each momentary switches that connect to ground
• Switch Indicator
  • Arduino Pin 10, 11 to each LEDs (use appropriate resistors)

Arduino Library Used

• Arduino MIDI Library

Features

• SW debouncing for 4 switch inputs for robust user experience
• Can recognise 4 inputs that emulate FS4, FS5, Tuner & tap tempo switch.

DIYable Parts

• Change the CC# to control different feature of your MIDI device
• Tune the debounceDelay value for your switch of choice

Todo

• Implement analog input feature