Stepper motor with driver module in Arduino - Step-by-Step Execution

Concept Flow - Stepper motor with driver module

Start

↓

Setup pins

↓

Initialize stepper

↓

Loop start

↓

Send step pulse

↓

Delay for speed

↓

Update step count

↓

Check if steps done?

No→Loop start

Yes↓

Stop motor

↓

End or repeat

The program sets up pins, then repeatedly sends pulses to the driver to move the motor step by step until the desired steps are done.

Execution Sample

Arduino

const int stepPin = 3;
const int dirPin = 4;
int steps = 200;

void setup() {
  pinMode(stepPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
  digitalWrite(dirPin, HIGH);
}

void loop() {
  for (int i = 0; i < steps; i++) {
    digitalWrite(stepPin, HIGH);
    delayMicroseconds(1000);
    digitalWrite(stepPin, LOW);
    delayMicroseconds(1000);
  }
  while(true) {}
}

This code moves the stepper motor 200 steps in one direction by sending pulses to the step pin with delays controlling speed.

Execution Table

Step	i (step count)	Condition i<steps	Action	Pin stepPin state	Delay (us)
1	0	True	Set stepPin HIGH	HIGH	1000
2	0	True	Set stepPin LOW	LOW	1000
3	1	True	Set stepPin HIGH	HIGH	1000
4	1	True	Set stepPin LOW	LOW	1000
5	2	True	Set stepPin HIGH	HIGH	1000
6	2	True	Set stepPin LOW	LOW	1000
...	...	...	...	...	...
399	199	True	Set stepPin HIGH	HIGH	1000
400	199	True	Set stepPin LOW	LOW	1000
401	200	False	Exit loop	LOW	0

💡 i reaches 200, condition i<200 is False, loop ends

Variable Tracker

Variable	Start	After 1	After 2	After 3	...	Final
i	-	0	1	2	...	200
stepPin state	LOW	HIGH	LOW	HIGH	...	LOW

Key Moments - 3 Insights

Why do we set stepPin HIGH and then LOW in each loop iteration?

Because the stepper driver moves the motor one step on the rising edge (HIGH) of the stepPin signal, then setting it LOW prepares for the next pulse. See execution_table rows 1-2.

What controls the speed of the motor steps?

The delayMicroseconds(1000) between setting stepPin HIGH and LOW controls how fast pulses are sent, thus controlling motor speed. See execution_table 'Delay (us)' column.

Why does the loop stop after 200 steps?

Because the for loop condition i < steps becomes false when i reaches 200, stopping pulses and motor movement. See execution_table last row.

Visual Quiz - 3 Questions

Look at the execution_table, what is the state of stepPin at step 3?

A Undefined

B LOW

C HIGH

D No change

💡 Hint

Check the 'Pin stepPin state' column at step 3 in the execution_table.

At which iteration does the loop condition become false?

A 199

B 200

C 201

D 100

💡 Hint

Look at the last row of execution_table where i reaches 200 and condition is false.

If delayMicroseconds is increased, how does the execution_table change?

A Delay values increase, motor steps slower

B Delay values decrease, motor steps faster

C No change in delay values

D Loop ends earlier

💡 Hint

Refer to the 'Delay (us)' column in execution_table and how delay controls speed.

Concept Snapshot

Stepper motor with driver module:
- Use two pins: DIR for direction, STEP for steps
- Set DIR pin HIGH or LOW to choose direction
- Send pulses on STEP pin: HIGH then LOW for each step
- Delay between pulses controls speed
- Loop for desired number of steps
- Stop after steps done

Full Transcript

This example shows how to control a stepper motor using a driver module with Arduino. First, pins for step and direction are set as outputs. Direction pin is set HIGH to choose rotation direction. Then, in the loop, a for loop runs for the number of steps needed. Each iteration sends a pulse by setting the step pin HIGH, waiting a short delay, then LOW, and waiting again. This pulse makes the motor move one step. The delay controls how fast the motor steps. When the loop finishes, the motor stops. The execution table traces each step pin change and delay. Variables like the step counter 'i' and pin states are tracked. Common confusions include why the step pin toggles HIGH then LOW, how speed is controlled by delay, and why the loop stops after the set steps. The quiz questions check understanding of pin states, loop exit, and delay effects. This visual trace helps beginners see exactly how the motor driver is controlled step by step.