Example Code for Arduino-Control Servo Angle

Hardware Preparation

• DFRduino UNO R3 (or similar) x 1
• Rotary Encoder Module (I2C) x 1
• Servo Motor x 1
• Jumper wires

Software Preparation

• Arduino IDE
• Download and install the Rotary Encoder Module Library. (About how to install the library?)
• Use the built-in Servo library (included with Arduino IDE).

Other Preparation Work

Ensure the rotary encoder's I2C address is set to 0x54 via the DIP switches on the back of the module.I2C Setting Method

Sample Code

/*!
 * @file        setSensor.ino
 * @brief       This demo shows tha thow to control servo angle by the encoder 
 * @copyright   Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
 * @licence     The MIT License (MIT)
 * @author      [qsjhyy]([email protected])
 * @version     V0.1
 * @date        2021-09-15
 * @get from    https://www.dfrobot.com
 * @url         https://github.com/DFRobot/DFRobot_VisualRotaryEncoder
 */
#include <DFRobot_VisualRotaryEncoder.h>

/*
Instantiate an object to drive our sensor;
Set address according to the encoder DIP:
| 1 | 2 | ADDR |
|---|---|------|
| 0 | 0 | 0x54 |
| 0 | 1 | 0x55 |
| 1 | 0 | 0x56 |
| 1 | 1 | 0x57 |
*/
DFRobot_VisualRotaryEncoder_I2C sensor(/*iicAddr = */0x54, /*iicBus = */&Wire);

#include <Servo.h>

Servo myservo;
int pos = 0;    // Init servo angle
void setup()
{
  myservo.attach(9);  // Set servo connection pin 

  Serial.begin(115200);

  // Init sensor 
  while( NO_ERR != sensor.begin() ){
    Serial.println("Communication with device failed, please check connection");
    delay(3000);
  }
  Serial.println("Begin ok!");

  /**
   * Set encoder gain coefficient, accuracy value to rotate one detent 
   * Accuracy range: 1~51, the minimum is 1 (light up one LED about every 2.5 turns), the maximum is 51 (light up one LED every one detent rotation)
   * Return range: 1-51
   */
  sensor.setGainCoefficient(51);

  /**
   * Get current encoder gain coefficient, accuracy value to rotate one detent 
   * Accuracy range: 1~51, the minimum is 1 (light up one LED about every 2.5 turns), the maximum is 51 (light up one LED every one detent rotation)
   * Return range: 1-51
   */
  uint8_t gainCoefficient = sensor.getGainCoefficient();
  Serial.print("Encoder current gain coefficient: ");
  Serial.println(gainCoefficient);

  Serial.println();
  delay(1000);
}

void loop()
{
  /**
   * Detect if the button is pressed 
   * Return true, button pressed. Return false: button unpressed 
   */
  if(sensor.detectButtonDown()){
    /**
     * Set the encoder count value
     * value Range[0, 1023], setting invalid when out of range
     * In this example, when the button is detected to be pressed, reset the encoder value to zero, then all the LEDs that light up before switch off.
     */
    sensor.setEncoderValue(0);
  }

  /**
   * Get encoder current count value
   * Return value range: 0-1023
   * Map the encoder value to servo angle 
   */
  uint16_t encoderValue = sensor.getEncoderValue();
  Serial.print("The encoder currently counts: ");
  Serial.println(encoderValue);
  pos = map(encoderValue, 0, 1023, 10, 170);
  myservo.write(pos);
  Serial.println();
  delay(1000);
}

Result