Control Speed of Stepper Motor 28BYJ-48 with potentiometer

Project Video
Project Details

This is the Arduino code to control the speed of 28BYj-48 Stepper with potentiometer.

Project Code

 * This is Arduino code to control Speed of 28BYj-48 
 * Stepper motor with potentiometer.  
 * Written by Ahmad Shamshiri for Robojax
 * on Jun 30, 2019 at 19:04 in Ajax, Ontario, Canada
 Watch the video instruction for this sketch:
You can get the wiring diagram from my Arduino Course at
Learn Arduino step by step with all library, codes, wiring diagram all in one place
visit my course now

Watch main stepper motor video:

If you found this tutorial helpful, please support me so I can continue creating 
content like this. You can support me on Patreon
or make donation using PayPal

If you found this tutorial helpful, please support me so I can continue creating 
content like this. You can support me on Patreon
or make donation using PayPal

 * Code is available at

 * This code is "AS IS" without warranty or liability. Free to be used as long as you keep this note intact.* 
 * This code has been download from
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see . 

const int desiredValue = 20;//time in sec for a Revolution

const int dir = 2; // 1 for CW and 2 for CCW

int Pin1 = 10;//IN1 is connected to 10 
int Pin2 = 11;//IN2 is connected to 11  
int Pin3 = 12;//IN3 is connected to 12  
int Pin4 = 13;//IN4 is connected to 13 
int potPin = A0;// center pin of pot is connected to this pin
int vcc2 = 2;// additional 5V for potentiometer

int pole1[] ={0,0,0,0, 0,1,1,1, 0};//pole1, 8 step values
int pole2[] ={0,0,0,1, 1,1,0,0, 0};//pole2, 8 step values
int pole3[] ={0,1,1,1, 0,0,0,0, 0};//pole3, 8 step values
int pole4[] ={1,1,0,0, 0,0,0,1, 0};//pole4, 8 step values

int poleStep = 0; 
int calcDelayfromTime(int t);
void driveStepper(int c);
int N = calcDelayfromTime(desiredValue);

void setup() 
 pinMode(Pin1, OUTPUT);//define pin for ULN2003 in1 
 pinMode(Pin2, OUTPUT);//define pin for ULN2003 in2   
 pinMode(Pin3, OUTPUT);//define pin for ULN2003 in3   
 pinMode(Pin4, OUTPUT);//define pin for ULN2003 in4 
 pinMode(vcc2, OUTPUT);//define pin as output for 5V for pot
 digitalWrite(vcc2, HIGH);//set vcc2 pin HIGH to have 5V for pot 
 Serial.println("Robojax Stepper Control");
 Serial.print("Max time per rev set: ");
 Serial.print(" loop delay: ");
  delay(4000);//give use time to read
}// setup

 void loop() 
  // Robojax Stepper code S8BYJ-48
 if(dir ==1){ 
 }else if(dir ==2){ 
 int potValue =analogRead(potPin);// read potentiometer value
 int speed = map(potValue,0, 1023, 1,N);


}// loop

int calcDelayfromTime(int t){
  return ((t-5)/4)+1;

 * @brief sends signal to the motor
 * @param "c" is integer representing the pol of motor
 * @return does not return anything
 * code June 2019
void driveStepper(int c)
     digitalWrite(Pin1, pole1[c]);  
     digitalWrite(Pin2, pole2[c]); 
     digitalWrite(Pin3, pole3[c]); 
     digitalWrite(Pin4, pole4[c]);   
}//driveStepper end here

Required File(s)