Arduino Rotary Encoder Interface

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Introduction

In a permanent magnet, brushless motor, a sensor or device known as a rotary encoder is utilized to detect the angle of the motor shaft. The question might come to your mind how this sensor works? The sensor generates an electrical signal when detecting any rational movement. And, thus, this helps to control the position or speed of any device. But, these types of sensors require a controller that drives them. For example, an Arduino. So, to understand how Arduino can drive the encoder, in this tutorial, we are going to Make an ” Arduino Rotary Encoder Interface “

Hardware Required

S.no	Component	Value	Qty
1.	Arduino UNO	–	1
2.	USB Cable Type A to B	–	1
3.	Rotary Encoder	–	1
4.	Jumper Wires	–	–

Circuit Diagram

Connection Table

Arduino	Rotary Encoder
GND	GND
5V	Vcc
D1	DT
D2	CLK

Arduino Code

 #define encoderOutA 2 // CLK pin of Rotary Enocoder
 #define encoderOutB 1 // DT pin of Rotary Enocoder
 
 int counter = 0; 
 int presentState;
 int previousState;  
 void setup() { 
   pinMode (encoderOutA,INPUT);
   pinMode (encoderOutB,INPUT);
   
   Serial.begin (9600);
      previousState = digitalRead(encoderOutA);   // Get current state of the encoderOutA
 } 
 void loop() { 
   presentState = digitalRead(encoderOutA); 
      if (presentState != previousState)
      {     
          if (digitalRead(encoderOutB) != presentState) 
          { 
       counter ++;
     } 
     else {
       counter --;
     }
     Serial.print("Position: ");
     Serial.println(counter);
   } 
   previousState = presentState; // Replace previous state of the encoderOutA with the current state
 }

Code Explanation

First, define the Arduino pins connected with the encoder pins. Then define the variables counters (initialize the count as 0), presentState, previousState to store the integer values.
In void setup, declare