External Midi Controller

[Ariesh]

hi, so i just saw this now and i'm planning todo a whole thread on this - but i managed to code an arduino with 4 bankakble midi over usb footswitches, and up to 4 potentiometers
I'm using the control-surface library, and it works.
 this is my code:

Code: [Select]

#include <Control_Surface.h> // Include the Control Surface library
 
// Instantiate a MIDI over USB interface
USBMIDI_Interface midi;
 
// Instantiate four Banks, with eight tracks per bank.
Bank<4> bank(8);
//   │       └───── number of tracks per bank
//   └───────────── number of banks
 
// Instantiate a Bank selector to control which one of the four Banks is active.
IncrementDecrementSelector<4> selector = {
    bank,       // Bank to manage
    {2, 3},     // Push button pins (increment, decrement)
    Wrap::Wrap, // Wrap around
};

// Instantiate an array of latched push buttons that send MIDI CC messages
// when pressed.
Bankable::CCButtonLatched<4> buttons[] {
  { bank, 4, 0x10 },
  //  │   │    └──── Base MIDI CC controller number
  //  │   └───────── Button pin number
  //  └───────────── Bank that changes the controller number
  { bank, 5, 0x11 },
  { bank, 6, 0x12 },
  { bank, 7, 0x13 },
};

// The bank controls the offset of the controller number relative to the
// button's base address. The amount of offset depends on the "number of
// tracks per bank" argument used when creating the bank. In this case,
// it's 8 tracks per bank, so for every bank you go up, 8 is added to the
// controller number of each button:
//
//         │  Button 1  │  Button 2  │  Button 3  │  Button 4  │  Offset
// ────────┼────────────┼────────────┼────────────┼────────────┤
// Bank 1  │    0x10    │    0x11    │    0x12    │    0x13    │  0×8=0
// Bank 2  │    0x18    │    0x19    │    0x1A    │    0x1B    │  1×8=8
// Bank 3  │    0x20    │    0x21    │    0x22    │    0x23    │  2×8=16
// Bank 4  │    0x28    │    0x29    │    0x2A    │    0x2B    │  3×8=24

// The array of pin numbers for LEDs that display the states of the buttons.
const pin_t ledPins[] = { 10, 11, 12, 13 };

// Get the length of an array
template <class T, size_t N> constexpr size_t length(T (&)[N]) { return N; }

static_assert(length(buttons) == length(ledPins),
              "Error: requires same number of buttons as LEDs");

CCPotentiometer knobsTop[] {
  {A0, MIDI_CC::General_Purpose_Controller_1},
  {A1, MIDI_CC::General_Purpose_Controller_2},
  {A2, MIDI_CC::General_Purpose_Controller_3},
  {A3, MIDI_CC::General_Purpose_Controller_4},
};

void setup() {
  Control_Surface.begin();  // Initialize the Control Surface
  for (auto pin : ledPins)  // Set the pinMode to output for all LEDs
      pinMode(pin, OUTPUT);
}

void loop() {
  Control_Surface.loop();  // Update the Control Surface

  // Loop over all buttons and LEDs
  for (size_t i = 0; i < length(buttons); ++i)
      // Update the LED states to reflect the toggled switch states
      digitalWrite(ledPins[i], buttons[i].getState() ? HIGH : LOW);
}

[Randall (Admin)]

Very cool.  Thanks for sharing.

What an awesome library to abstract away all the low level stuff.

[Ariesh]

i wnated something that would fit my pedalboard, so it has to be just the right size

with very easy modifications and a few multiplexers you can add virtually any number of buttons, and expression pedals as potentiometers

i forgot to mention this code also outputs the state of the button to an LED, and you can always wire and LED in line with any potntiometer if you want

[Peetem]

i wnated something that would fit my pedalboard, so it has to be just the right size

with very easy modifications and a few multiplexers you can add virtually any number of buttons, and expression pedals as potentiometers

i forgot to mention this code also outputs the state of the button to an LED, and you can always wire and LED in line with any potntiometer if you want

I bought a really large pedalboard and installed push buttons in the lower left corner.  Those are tied to my Teensy board and act as a midi controller.  In addition, because the Pi Stomp has stereo in/out, one channel has all my other foot pedals and electric guitar going through it and the other my acoustic.  So I essentially have two independent effect signal chains.