Pigpio Encoder

Version: 0.2.2

Requires Python 3

Python module for the KY040 rotary encoder.

This module has been developed for quickly interface a rotary encoder with Raspberry Pi. It's based on the pigpio library (cause it proved to be faster than rpi.GPIO or gpiozero libraries) so you need to install pigpio library and run pigpio daemon before starting your script.

Features

• Easy to setup callback functions for the Rotary Encoder and the Switch.
• The Rotary Encoder has customizable min and max values (default 0-100).
• The Rotary Encoder increase/decrease value is customizable (default 1).
• The Switch can be activated or not.
• The Switch can have two different functions for short press or long press.
• Both Rotary and Switch have a customizable debounce value (default 300ms)

Installation

• Install the pigpio library (check pigpio documentation for alternative installation method)
• sudo apt-get update
• sudo apt-get install pigpio python-pigpio python3-pigpio
• Install the pigpio_encoder library
• pip install pigpio_encoder (consider add --user option)
• start pigpio daemon
• sudo pigpiod

How to use

• import the module

  from pigpio_encoder import Rotary

• create a callback function for the Rotary Encoder.

  You must pass a positional argument to retrieve the counter value.

  def rotary_callback(counter):
      # some action with counter...

• create callbacks functions for the Switch

  If you intend to use the switch you must create at least the "short press" callback. The "long press" callback is necessary if you want to use that feature.

  def sw_short_callback():
      # some action...

  def sw_long_callback():
      # some action...
    ```

• create the rotary object

  here you setup the pin number as keyword argument. If you don't pass the switch parameter the switch won't be activated. You must use BCM numbering.

  my_rotary = Rotary(clk=pin, dt=pin, sw=pin)

• setup the rotary encoder

  here you can setup min and max values for the encoder, the increase/decrease value, a debouce value (default 300ms) and the callback function.

  my_rotary.setup_rotary(min=min_value, max=max__value, scale=scale_value, debounce=debounce_value, rotary_callback=rotary_callback)

• setup the switch

  if you have specified the switch pin when creating the encoder object, here you can setup the debounce value, the long press option and the callbacks.

  my_rotary.setup_switch(debounce=debounce_value, long_press=True, sw_short_callback=sw_short_callback, sw_long_callback=sw_long_callback)

• start the listener

  my_rotary.watch()

---

Basic example using default values

from pigpio_encoder import Rotary

def rotary_callback(counter):
    print("Counter value: ", counter)

def sw_short():
    print("Switch pressed")

my_rotary = Rotary(clk=27, dt=22, sw=17)
my_rotary.setup_rotary(rotary_callback=rotary_callback)
my_rotary.setup_switch(sw_short_callback=sw_short)

my_rotary.watch()

---

Example using all the Features

from pigpio_encoder import Rotary

def rotary_callback(counter):
    print("Counter value: ", counter)

def sw_short():
    print("Switch short press")

def sw_long():
    print("Switch long press")

my_rotary = Rotary(clk=27, dt=22, sw=17)
my_rotary.setup_rotary(min=10, max=300, scale=5, debounce=200, rotary_callback=rotary_callback)
my_rotary.setup_switch(debounce=200, long_press=True, sw_short_callback=sw_short, sw_long_callback=sw_long)

my_rotary.watch()

---

Thanks to...

• joan2937 for the awesome pigpio library
• Raphael Yancey for inspiring me this library with his similar project