SimpleEncoder

SimpleEncoder is a very simple, easy to use library for using rotary encoders with an Arduino.

To use it, you simply invoke the library by passing in the pin assignments from your encoder.

#include <SimpleEncoder.h>

const int BUTTON_PIN = 10;
const int PINA = 11;
const int PINB = 12;

SimpleEncoder encoder(BUTTON_PIN, PINA, PINB);

The library handles configuring the pins for you. Then to use the encoder, you can engage the library in a couple of different ways, all of which need to be in your loop method.

void loop() {
    if (encoder.CLOCKWISE) {
        //Code for upward motion
    }
    if (encoder.COUNTERCLOCKWISE) {
        //Code for downward motion
    }
}

Value Tracking

You can have SimpleEncoder track a value for you which gets incremented or decremented based on the direction of the encoder at the moment you check it.

#include <SimpleEncoder.h>

const int BUTTON_PIN = 10;
const int PINA = 11;
const int PINB = 12;
long myValue = 0;
long minValue = -100;
long maxValue = 100;

SimpleEncoder encoder(BUTTON_PIN, PINA, PINB, myValue, minValue, maxValue);

Then simply query the library for any changes in the encoder and if they exist, get the new value

void loop() {
    if(encoder.CHANGING) {
        myValue = encoder.VALUE;
    }
}

If you want to start tracking a value after you've already created your encoder, OR if you wish to alter the upper and lower limits, you can do it like this:

encoder.setLimits(lowerLimit, upperLimit, newValue);

You can also set the value to a specific number at any time, but it must be a number that is within the lower and upper limit:

encoder.setValue(newValue);

It's just that easy.

There are two example sketches that show how to use the library.

These are the public methods in the library:

clockwise() - Returns true if rotary moving clockwise
counterClockwise() - Returns true if rotary moving counter clockwise
buttonPressed() - Button was pressed
changing() - rotary is moving in either direction
idle() - rotary is idle and not changing
getValue() - get the value of the variable being tracked

And these are the alternate MACROS that can be used instead of the method names:

CLOCKWISE - Returns true if rotary moving clockwise
COUNTERCLOCKWISE - Returns true if rotary moving counter clockwise
BUTTON_PRESSED - Button was pressed
CHANGING - rotary is moving in either direction
IDLE - rotary is idle and not changing
VALUE - get the value of the variable being tracked

Make sure that your encoder has 5v connected to it - usually sourced from the Arduino, and that Pin C is connected to ground or things won't work properly.

Here is a schematic of how your rotary encoder should be connected. The yellow nodes indicate where the encoder should be connected to the Arduino in accordance with this library.

If you're interested, I made a PCB breakout board that I've already ordered and tested and it works perfectly.

Enjoy!