Running two NEMA 17 motors, one by one, using the Arduino Uno I am new to Arduino. I am trying to run two stepper motors NEMA 17 through respective A4988 driver and controlling via Arduino Uno.

The thought is that first stepper motor will carry out a first horizontal scan and then as it reaches to its initial position, second stepper motor will move a single step in vertical direction. This is a kind of raster scan that I want to perform with both motors. 

When I am running the code, only horizontal scan motor is running and vertical scan motor is not moving. I have checked my circuit, motors and drivers and everything is working fine. I think there is some mistake in my code. It is a basic level code and I would really appreciate the help for helping me out. 

int x, y; //stepper motor 'x' and stepper motor 'y'
#define BAUD (9600)


void setup() 
{
  Serial.begin(BAUD);
  pinMode(6,OUTPUT); // Enable for x
  pinMode(5,OUTPUT); // Step for x
  pinMode(4,OUTPUT); // Dir for x
  digitalWrite(6,LOW); // Set Enable low for x

  pinMode(9,OUTPUT); // Enable for y
  pinMode(8,OUTPUT); // Step for y
  pinMode(7,OUTPUT); // Dir for y
  digitalWrite(9,LOW); // Set Enable low for y
}

void loop() 
{

  digitalWrite(9,LOW); // Set Enable low for y



  for(y = 0; y &lt; 20; y++)
  {
     digitalWrite(6,LOW); // Set Enable low for x
     digitalWrite(4,HIGH); // Set Dir high for x - Clockwise

     Serial.println("CLOCKWISE HORIZONTAL SCANNING IN PROGRESS");

     for(x = 0; x &lt; 50; x++) // Loop 50 times
     {
      digitalWrite(5,HIGH); // Output high for x
      delay(10); // Wait
      digitalWrite(5,LOW); // Output low for x
      delay(100); // Wait
     }

    digitalWrite(6,LOW); // Set Enable low for x
    digitalWrite(4,LOW); // Set Dir low for x - Anticlockwise

    Serial.println("ANTICLOCKWISE HORIZONTAL SCANNING IN PROGRESS");

    for(x = 0; x &lt; 50; x++) // Loop 50 times
    {
      digitalWrite(5,HIGH); // Output high
      delay(10); // Wait
      digitalWrite(5,LOW); // Output low
      delay(100); // Wait
    }

    Serial.println("ONE STEP CLIMB ON VERTCAL AXIS");

    digitalWrite(7,HIGH); // Set Dir high for y

    digitalWrite(8,HIGH); // Output high for y
    delay(100); // Wait
    digitalWrite(8,LOW); // Output low for y
    delay(100); // Wait  
  }

  digitalWrite(9,LOW); // Set Enable low for y
  digitalWrite(7,LOW); // Set Dir low for y

  Serial.println("RESETTING ON VERTCAL AXIS");

  for(y = 0; y &lt; 20; y++) // Loop 20 times
    {
      digitalWrite(8,HIGH); // Output high for y
      delay(10); // Wait
      digitalWrite(8,LOW); // Output low for y
      delay(100); // Wait
    }

}


Do i need to look after the delay being provided??
A minor issue that probably won't affect your result is that 

Serial.println("ONE STEP CLIMB ON VERTCAL AXIS");
--&gt; digitalWrite(9,LOW);  // This line 'needs' adding
digitalWrite(7,HIGH); // Set Dir high for y


I can't see anything in the code that will prevent the motors running, OK it will take ~13 seconds to start moving, but it should move.

So - without any hardware attached to the motor spindles - is it possible to switch the motors over to check for a wiring breakage issue?  With one motor working and one not it implies to me that either the motor is broken, the wiring is broken or the driver circuit is broken.  If the fault moves then its a motor/wiring fault if it stays the same then its a driver fault.