How to drive a stepper motor easily using A4988 and Arduino

Driving a stepper motor used to be complicated enough when we have to build a driver by ourselves. But since there are many kinds of driver modules out there, driving a stepper motor is not that hard anymore. In this video, we will learn how to use the A4988 stepper driver.

A4988 stepper motor driver specification :

• Max. Operating Voltage: 35V
• Min. Operating Voltage: 8V
• Max. Current Per Phase: 2A
• Microstep resolution: Full step, ½ step, ¼ step, 1/8 and 1/16 step
• Reverse voltage protection: No
• Dimensions: 15.5 × 20.5 mm (0.6″ × 0.8″)
• Short-to-ground and shorted-load protection
• Low RDS(ON) outputs
• Thermal shutdown circuitry

A4988 stepper motor driver pinout

A4988 stepper motor driver with Arduino Tutorial

In this tutorial, we will try to use this stepper motor with an Arduino. So let’s start with the wiring diagram.

You can use 47uF of a capacitor at Vmot and GND pins. In this tutorial I use the NEMA17 stepper motor.

Arduino Code

The first sketch we will try to use is a stepper spin clockwise and counterclockwise with a second delay between them.

// Define pin connections & motor's steps per revolution
const int dirPin = 2;
const int stepPin = 3;
const int stepsPerRevolution = 500;
int stepDelay=2000;

void setup()
{
  // Declare pins as Outputs
  pinMode(stepPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
}
void loop()
{
  //clockwise
  digitalWrite(dirPin, HIGH);

  // Spin motor
  for(int x = 0; x < stepsPerRevolution; x++)
  {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(stepDelay);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(stepDelay);
  }
  delay(1000); // Wait a second
  
  //counterclockwise
  digitalWrite(dirPin, LOW);

  // Spin motor
  for(int x = 0; x < stepsPerRevolution; x++)
  {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(stepDelay);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(stepDelay);
  }
  delay(1000); // Wait a second
}

After that I add a trimmer to the circuit and will use the trimmer as speed adjuster. Here’s the wiring diagram.

// Define pin connections & motor's steps per revolution
const int dirPin = 2;
const int stepPin = 3;
const int stepsPerRevolution = 500;
int stepDelay = 700;

void setup()
{
  // Declare pins as Outputs
  pinMode(stepPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
  Serial.begin(9600);
}
void loop()
{
  //clockwise
  digitalWrite(dirPin, HIGH);
  int pot = analogRead(A0);
  stepDelay=map(pot, 0, 1023, 10000, 0);
  Serial.println(stepDelay);
  // Spin motor
  digitalWrite(stepPin, HIGH);
  delayMicroseconds(stepDelay);
  digitalWrite(stepPin, LOW);
  delayMicroseconds(stepDelay);
}

And here’s the complete video tutorial