Figure 3: The quadrature outputs of a 512 pulse per revolution optical encoder showing the phase relationships between the A and B signal outputs Image source: Digi-Key Electronics Only the single A output was used in this example as the encoder was applied as a tachometer, measuring the rotational speed of a motor.
Rotary Encoder Interfacing with Arduino The Interfacing of the rotary encoder with an Arduino Uno can be done as mentioned below.