EndlessPotentiometer.h

This library is based on Bjørn Brandal's work here. It is a library for detecting the direction and values from an endless rotary potentiometer like those found on the Novation Circuit and the Native Instruments KORE/KORE2 controllers.

The library has purposely left out the use of analogRead() so that it can be framework-agnostic. This means that if you want to use Mozzi, it'll still work since it evaluates the values passed and not by calling those values itself.

Here is an example of how to use this:

#include <Arduino.h>
#include <EndlessPotentiometer.h>

#define PIN_A A0
#define PIN_B A1

// Uncomment for debug
#define DEBUG true
#define MAX_POT_VALUE 1023

int value=0;
int localValue=0;
int altValue=0;

EndlessPotentiometer pot;

void setup() {
  if (DEBUG) {
    Serial.begin(115200);

    // You can modify the default parameters tho this is optional if you are happy with the default
    // Settings.
    pot.threshold = 3;      // Optional
    pot.sensitivity = 1.8;  // Optional
    pot.maxValue = 255;     // Optional
    pot.minValue = -255;    // Optional
  }
}

void loop()
{
  pot.updateValues(analogRead(PIN_A), analogRead(PIN_B));

  if (pot.isMoving) {
    // Use this method if you are controlling a single value with this pot. The object comes with its own
    // Internal value variable to keep track of.
    value = pot.value;

    // Or you can pass the value you want calculated. This is useful if all your values use the same
    // range.
    localValue = pot.getValue(localValue);

    // However, if you want to take advanatage of the relative nature of the component, you may
    // instead be interested in using the value changed instead. This will allow you to use the
    // same pot with different values ranges. But there is a few more lines of code needed.
    if (pot.direction == pot.CLOCKWISE) {
      altValue = altValue + pot.valueChanged;
    } else if (pot.direction == pot.COUNTER_CLOCKWISE) {
      altValue = altValue - pot.valueChanged;
    }

    if (altValue < 0) {
      altValue = 0;
    } else if (altValue > MAX_POT_VALUE) {
      altValue = MAX_POT_VALUE;
    }

    if (DEBUG) {
      Serial.print("direction: ");
      Serial.print(pot.direction);
      Serial.print(" value: ");
      Serial.print(value);
      Serial.print(" localValue: ");
      Serial.print(localValue);
      Serial.print(" altValue: ");
      Serial.print(altValue);
      Serial.print(" ValueChanged: ");
      Serial.println(pot.valueChanged);
    }
  }

  if (DEBUG) {
    delay(10);
  }
}