Arduino and Stepper Motors

Hi I am using the following code to run stepper motor through DRV8825 driver.

#define DIR_PIN          2
#define STEP_PIN         3
#define ENABLE_PIN       4

void setup() {
  pinMode(DIR_PIN,    OUTPUT);
  pinMode(STEP_PIN,   OUTPUT);
  pinMode(ENABLE_PIN, OUTPUT);
  digitalWrite(ENABLE_PIN, LOW);
  digitalWrite(DIR_PIN, LOW);
}

void loop() {
  digitalWrite(STEP_PIN, HIGH);
  digitalWrite(STEP_PIN, LOW);
  delayMicroseconds(200);
}

I am confused about the loop function as I don't understand the correct way to send the pulse.Should it be like

digitalWrite(STEP_PIN, HIGH);
digitalWrite(STEP_PIN, LOW);
delayMicroseconds(200);

or

digitalWrite(STEP_PIN, HIGH);
delayMicroseconds(200);
digitalWrite(STEP_PIN, LOW);
delayMicroseconds(200);

PLEASE HELP!!!

The stepper driver executes a step on the rising edge of the STEP input, so no delay is necessary if using digitalWrite(), as it is very slow.

This is all you need to cause the driver to execute one step. Any other delays are up to you.

digitalWrite(STEP_PIN, HIGH);
digitalWrite(STEP_PIN, LOW);

Note: If you were to use direct port access, the STEP pulse must be HIGH for at least 1.9 us, and the following LOW must also have 1.9 us duration.

I want to operate a NEMA23 with step angle 1.8 degree using digital motor driver DM542 at 10RPS synchronous to the clock pulse. I know the basic program to run a stepper motor using a driver but i dont have enough knowledge to get a particular required RPS. If someone can provide me with a valid code and connections.

These links may help Simple Stepper Code Stepper Motor Basics

In the code examples I have used descriptive names for the variables that should help with understanding the process.

...R