beatonma / whammy-arduino

An Arduino-based MIDI controller for the Digitech Whammy IV effects pedal.

whammy-arduino

A MIDI controller for the Digitech Whammy IV effects pedal.

Demo on Youtube

The implementation currently provides these modes:

• Active (LED blue): Ramp towards toe-down when active, ramp towards heel-down when inactive.
• Waves (LED white):
  • Sine: ramp up and down following a nice smooth sine wave /‾\_/‾\_
  • Sawtooth up: linear ramp up, immediate return to zero ////
  • Sawtooth down: linear ramp down, immediate return to maximum `\\
  • Triangle: linear ramp up and down /\/\/
• Sequencer (LED red):
  • Square _‾_‾
  • "Map of the Problematique"
  • Octaves -2, -1, 0, +1, +2
  • Random sequence
• Scale (LED yellow): Random pedal positions quantised to a musical mode (Phrygian, Lydian, etc)
• Random position (LED green): unquantised, random pedal positions.
• 'Chaos' (LED cyan): random selection from the above modes.

Hardware

• Wiring diagram here
• Arduino Nano clone
• 3 momentary buttons
• One linear potentiometer
• MIDI port
• RGB LED
• A few resistors, wire, case, etc.

Controls

On/off: activate the pedal.
Modifier + On/off: Toggle between momentary and latching activation. Momentary/latching mode persists in EEPROM between sessions so you don't need to change it every time.

Mode: move to the next pedal mode.
Modifier + Mode: move to previous mode.

Tempo potentiometer: Turn to change speed of all pedal functions.
Modifier + Tempo potentiometer: Limit the maximum range of the pedal position for tasteful vibrato-like operation ^{[citation needed]}.

Modifier: Tap to change the musical mode used in 'quantized scale' mode.

In all modes, the LED brightness indicates the effective position of the pedal - brighter means toe-down, darker means heel-down.

monitor.pd

If you want to work on this project without going mad from constant atonal wee-woo noises, open monitor.pd with Pure Data to see a visualisation of the MIDI messages instead.

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This project kept me busy while isolating with Covid 19 in April 2022. The illness provided some gnarly headaches and this project did not help with that whatsoever. Fun though.