Contact: www.juanlittledevil.com (juanlittledevil at gmail.com)
This is actually my second iteration of this stick not counting the version written specifically for the iElectribe app. The first iteration was done using a library I found online, but I quickly realized it's limitations. So this time I decided to stick to the supplied libraries. Well almost, I'm using two libraries which I found were quite useful, be sure to read the entire documentation before proceeding.
I wanted this controller to be super flexible. In total you can control 16 channels with 16 banks for 8 knobs for cc control, and full keboard range. You can also assign note to the buttons according the 16 pre-defined musical scales. You can also transpose the scales so they key changes while you get to play the same buttons. This means you can jam the same buttons and select a different key. This feature I modled after the way the new Electribe drum machines deal with scales and keys. Other apps do this as well; Gadget and Animoog to name a couple.
I'm using a Teensy 2.0++ and it is configured as with the following pinout:
pins 0 to 15 are connected to momentary switches which are arranged in a matrix of 4 x 4 where pin 0 is on the lower left and 15 is on the upper right.
pins 16 - 19 connect to an arcade joystick where 16=Right, 17=Down, 18=Left, 19=Up
pins 20 - 35 are connected to the matrix as well and match the push buttons so that 20 is on the lower left and 35 is on the upper right.
38 - 45 are the analogue pins, these connect to 8 potentiometers.
NOTE: Please read the teensy documentation and take special not to to include pullup resistors where needed. Depending on which version of the teensy you intend to use you may have to use resistors for a couple of pins connected to switches as well as those which connect to the LEDs.
the SmoothAnalogInput.h library was installed separately. https://github.com/rl337/Arduino/tree/master/libraries/SmoothAnalogInput
The joystick is used to select different modes.
To select the MIDI Channel hold the joystick in the up position. Part selection is as follows.
` ^ (13) (14) (15) (16) `
` | ( 9) (10) (11) (12) `
` ( 5) ( 6) ( 7) ( 8) `
` ( 1) ( 2) ( 3) ( 4) `
A blinking light will indicate the currently selected MIDI channel as long as the stick is in the up position.
There are 16 bank of 8 knobs. Each knob will send a MIDI cc message. The knobs are arranged as shown here.
' (1) (2) (3) (4) '
' (5) (6) (7) (8) '
You have access to all 128 control message parameters. Pressing down button (1) while holding the joystick in the down position will set the knobs with the first 8 messages, starting from cc 0 (bank select) to cc 7 (volume). Pressing the next button, button (2), will set the knobs from cc 8 to cc 15 and so on. For info on MIDI values see. http://nickfever.com/music/midi-cc-list
The following shows the bank order.
` (13) (14) (15) (16) `
` ( 9) (10) (11) (12) `
` | ( 5) ( 6) ( 7) ( 8) `
` v ( 1) ( 2) ( 3) ( 4) `
A solid lit led will indicate the currently selected part.
Press and hold left on the stick while pressing a button to select which octave the buttons will play. The default is C3 where C3 (note 36) is mapped to the bottom left button and so on. You can easily navigate through the entire key range this way. By default pressing keys will play a chromatic scale, however this can be changed see below. A blinking light will indicate the current octave.
` (13) (14) (15) (16) `
` <-- ( 9) (10) (11) (12) `
` ( 5) ( 6) ( 7) ( 8) `
` ( 1) ( 2) ( 3) ( 4) `
` (13) (14) (15) (16) `
` --> ( 9) (10) (11) (12) `
` ( 5) ( 6) ( 7) ( 8) `
` ( 1) ( 2) ( 3) ( 4) `
The right direction of the stick enables a multi-mode selection as follows.
While holding the stick to the right position press button (1) to cycle through the 12 keys. By default the scale will play in the key of C, but pressing the button will transpose the scale by half a step. An slow blinking LED will light up and indicate which key is currently selected. The lit LED maps as follows:
(1) - C
(2) - C#
(3) - D
(4) - D#
(5) - E
(6) - F
(7) - F#
(8) - G
(9) - G#
(10) - A
(11) - A#
(12) - B
While holding the stick to the right position press button (2) to cycle through 17 scales. By default the scale played is a chromatic scale with all 12 steps. However, enabling scales will change it so that only keys in that particular scale are played. A fast led will light up indicating the currently selected scale but only for scales 1 to 16. scale 17 (chromatic) will not show a fast blinking light, you will still see the slow blinking light however. Here is a breakdown of the different scale modes:
(1) Major w-w-h-w-w-w-h
(2) Natural Minor w-h-w-w-h-w-w
(3) Harmonic Minor w-h-w-w-h-3-h
(4) Jazz/Melodic Minor w-h-w-w-w-w-h
(5) Dorian w-h-w-w-w-h-w
(6) Phrygian h-w-w-w-h-w-w
(7) Spanish h-3-h-w-h-w-w
(8) Lydian w-w-w-h-w-w-h
(9) Diminished w-h-w-h-w-h-w
(10) Persian h-3-h-h-w-3-h
(11) Arabian w-w-h-h-w-w-w
(12) Blues 3-w-h-h-3-w
(13) Scottish w-3-2-2-3
(14) Hirojoshi w-h-3-h-3
(15) Major Pentatonic w-w-3-w-3
(16) Minor Pentatonic 3-w-w-3-w
(17) (defualt) chromatic.
While holding the stick to the right position press button (3) to toggle latch mode off and on. By default latch mode is enabled this means that values on banks are remembered and the unit will not send MIDI information until the current value matches the previous value. This prevents sudden jumbs in values sent to MIDI instruments when selecting different banks.
I left the ability to disable this since some software and MIDI hardware have latching functions themselves. If the software you are using has this features you should probably disable this.
While holding the stick to the right position press button (4) to toggle this mode off and on. By default it is on but this behavior can easily be changed by setting the global variale cc_joystick_mode to false.
I felt that it would sometimes be nice to send cc values, this works well specially if you want to use the joystick to navigate clips like in an app like modstep on iOS. This mode sacrifices 4 cc values which will be set to 1 when the joystick is moved in one of the 4 directions and 0 when the joystick is returned to the center. The 4 values used are:
midi 16, cc 124;
midi 16, cc 125;
midi 16, cc 126;
midi 16, cc 127;
This is the default mode. In this mode the buttons imply play midi notes. While in the center position
Default settings can be easily changed in the code. I've created a number of global variables to make editing default values easy. This code is here for all of our enjoyment if you run into issues be sure to read through the code first before reaching out to me as my time for responding to questions is very limited.