Arduino - Potentiometer Control Stepper Motor

use potentiometer to control stepper motor turning speed

Highlight: A potentiometer is able to output a very stable signal with a range of 0 to 100.

#include <Stepper.h>
const int stepsPerRevolution = 2048;
const int rpm = 12;
Stepper stepper1 = Stepper(stepsPerRevolution, 8, 10, 9, 11);

int rawValue;
int oldValue;
byte potPercentage;
byte oldPercentage;

void setup() {
  Serial.begin(115200); // set serial monitor to this baud rate
}

void loop() {
  // read input twice
  rawValue = analogRead(A0);
  rawValue = analogRead(A0); // double read

  // ignore bad hop-on region of a pot by removing 8 values at both extremes
  rawValue = constrain(rawValue, 8, 1015);

  // add some deadband
  if (rawValue < (oldValue - 4) || rawValue > (oldValue + 4)) {
    oldValue = rawValue;
    // convert to percentage
    potPercentage = map(oldValue, 8, 1008, 0, 100);

    // Only print if %value changes
    if (oldPercentage != potPercentage) {
      Serial.print("Pot percentage is: ");
      Serial.print(potPercentage);
      Serial.println(" %");
      oldPercentage = potPercentage;
    }
  }

 //stepper motor speed control
  stepper1.setSpeed(rpm * potPercentage / 100);
  stepper1.step(stepsPerRevolution);
  delay(10);
}