KY-040 Rotary Encoder Module

KY-040 Rotary Encoder

KY-040 Rotary Encoder PinOut

Keyes Rotary Encoder Schematic

KY-040 Evaluation Circuit

KY-04 Connection to the Arduino

Arduino Sketch

int pinA = 3;  // Connected to CLK on KY-040

int pinB = 4;  // Connected to DT on KY-040
int encoderPosCount = 0;
int pinALast; 
int aVal;
boolean bCW;
void setup()

{
  pinMode (pinA,INPUT);
  pinMode (pinB,INPUT);
  /* Read Pin A
  Whatever state it's in will reflect the last position   
  */
  pinALast = digitalRead(pinA);
  Serial.begin (9600);
}
void loop()

{
  aVal = digitalRead(pinA);
  if (aVal != pinALast)

  {

    // Means the knob is rotating
    // if the knob is rotating, we need to determine direction
    // We do that by reading pin B.
    if (digitalRead(pinB) != aVal)

    { 

      // Means pin A Changed first - We're Rotating Clockwise
      encoderPosCount ++;
      bCW = true;
    }

    else

    {

      // Otherwise B changed first and we're moving CCW
      bCW = false;
      encoderPosCount--;
    }
    Serial.print ("Rotated: ");
    if (bCW)

    {
      Serial.println ("clockwise");
    }

    else

    {
      Serial.println("counterclockwise");
    }
    Serial.print("Encoder Position: ");
    Serial.println(encoderPosCount);
  }
  pinALast = aVal;

}

Sumber
Keyes KY-040 Arduino Rotary Encoder User Manual

Where to buy
KY-040 Rotary Encoder Module

KY-040 Rotary Encoder Module