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Arduino/ESP library to simplify reading rotary encoder data.

ESPRotary

Arduino/ESP library to simplify reading rotary encoder data.

Description

This library allows you read out interactions with a rotary encoder and act on them. It uses callback functions to be notified when the rotary encoder changes.

It has been tested with Arduino, ESP8266 and ESP32 devices.

To see the latest changes to the library please take a look at the Changelog.

If you find this library helpful please consider giving it a ⭐️ at GitHub and/or buy me a ☕️. Thanks!

Some of the code based of this library is based on code from PJRC.

How to Use

Definition

  • Use the begin() or the parameterized constructor to create a new instance of the class
  • Encoder produce different numbers of "click" on a single turn.
  • You can specify the number of clicks in the constructor, or via a setter function
    • void setStepsPerClick(int steps)
    • int getStepsPerClick() const

Callback Handlers

  • The library provides several callback handlers to detect events
    • void setChangedHandler(CallbackFunction f)
    • void setRightRotationHandler(CallbackFunction f)
    • void setLeftRotationHandler(CallbackFunction f)
    • void setUpperOverflowHandler(CallbackFunction f)
    • void setLowerOverflowHandler(CallbackFunction f)
  • The library does not detect button clicks. You have to use a seperate library for this, e.g. Button2.

Ranges

  • In the constructor you can define an upper and a lower treshhold. The encoder value will not be bypass these values.
  • There are also getter and setter functions the these values
    • void setUpperBound(int upper_bound)
    • void setLowerBound(int lower_bound)
    • int getUpperBound() const
    • int getLowerBound() const

Reading out information

  • The class allows you the get the position and the direction after a click using these function:
    • int getPosition() const
    • byte getDirection() const
    • String directionToString(byte direction) const

Speed

  • You can define the speed, i.e. the increment the a single click in the constructor
  • There is also a getter and setter function for this
    • void setIncrement(int inc);
    • int getIncrement() const

The Loop

  • For the class to work, you need to call the loop() member function in your sketch's loop() function.
  • See the examples for more details.

IDs for Encoder Instances

  • Each enocder instance gets a unique (auto incremented) ID upon creation.
  • You can get a encoders' ID via getID().
  • Alternatively, you can use setID(int newID) to set a new one. But then you need to make sure that they are unique.
  • You can also use the == operator to compare encoders

Notes

Class Definition

These are the constructor and the member functions the library provides:

    ESPRotary();
    ESPRotary(byte pin1, byte pin2, byte steps_per_click = 1, int lower_bound = INT16_MIN, int upper_bound = INT16_MAX, int inital_pos = 0, int increment = 1);

    void begin(byte pin1, byte pin2, byte steps_per_click = 1, int lower_bound = INT16_MIN, int upper_bound = INT16_MAX, int inital_pos = 0, int increment = 1);

    int getPosition() const;
    void resetPosition(int p = 0, bool fireCallback = true);

    byte getDirection() const;
    String directionToString(byte direction) const;

    void setIncrement(int inc);
    int getIncrement() const;

    void setUpperBound(int upper_bound);
    void setLowerBound(int lower_bound);
    int getUpperBound() const;
    int getLowerBound() const;

    void setStepsPerClick(int steps);
    int getStepsPerClick() const;

    void setChangedHandler(CallbackFunction f);
    void setRightRotationHandler(CallbackFunction f);
    void setLeftRotationHandler(CallbackFunction f);
    void setUpperOverflowHandler(CallbackFunction f);
    void setLowerOverflowHandler(CallbackFunction f);

    void loop();

Installation

Open the Arduino IDE choose "Sketch > Include Library" and search for "ESP Rotary". Or download the ZIP archive (https://github.com/lennarthennigs/ESPRotary/zipball/master), and choose "Sketch > Include Library > Add .ZIP Library..." and select the downloaded file.

License

MIT License

Copyright (c) 2017-2022 Lennart Hennigs

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.