Easy Driver Examples

This example is exactly like 1.5 in setup, but allows you to specify the exact RPM of the motor. It will spin the motor at that speed as long as the button is held down.

Example 1.8: Fine speed control of two motors with a joystick

Example 2: Moving back and forth

Example 3: Using a pre-built library - AccelStepper

Example 4: Running multiple stepper motors

Example 5: Changing motor speed

The code for this example is shown below:

// Example5 code for Brian
          Schmalz's Easy Driver Example page

//
          http://www.schmalzhaus.com/EasyDriver/EasyDriverExamples.html

#include <AccelStepper.h>

// Define the stepper and the pins it will use

AccelStepper stepper1(AccelStepper::DRIVER, 9, 8);

// Define our three input button pins

#define LEFT_PIN 4

#define STOP_PIN 3

#define RIGHT_PIN 2

// Define our analog pot input pin

#define SPEED_PIN 0

// Define our maximum and minimum speed in steps
          per second (scale pot to these)

#define MAX_SPEED 500

#define MIN_SPEED 0.1

void setup() {

  // The only AccelStepper value we have to
          set here is the max speeed, which is higher than we'll ever go

stepper1.setMaxSpeed(10000.0);

  // Set up the three button inputs, with
          pullups

pinMode(LEFT_PIN, INPUT_PULLUP);

pinMode(STOP_PIN, INPUT_PULLUP);

pinMode(RIGHT_PIN, INPUT_PULLUP);

}

void loop() {

  static float current_speed =
          0.0;         // Holds
          current motor speed in steps/second

  static int analog_read_counter =
          1000;    // Counts down to 0 to fire analog
          read

  static char sign =
          0;                    







          // Holds -1, 1 or 0 to turn the motor on/off and control
          direction

  static int analog_value =
          0;             







          // Holds raw analog value.

  // If a switch is pushed down (low), set the
          sign value appropriately

if (digitalRead(LEFT_PIN) == 0) {

sign = 1;

}

  else if (digitalRead(RIGHT_PIN) == 0)
          {

sign = -1;

}

else if (digitalRead(STOP_PIN) == 0) {

sign = 0;

}

  // We only want to read the pot every so
          often (because it takes a long time we don't

  // want to do it every time through the main
          loop).

if (analog_read_counter > 0) {

analog_read_counter--;

}

else {

analog_read_counter = 3000;

    // Now read the pot (from 0 to
          1023)

    analog_value =
          analogRead(SPEED_PIN);

    // Give the stepper a chance to
          step if it needs to

stepper1.runSpeed();

    //  And scale the pot's
          value from min to max speeds

    current_speed = sign *
          (((analog_value/1023.0) * (MAX_SPEED - MIN_SPEED)) +
          MIN_SPEED);

    // Update the stepper to run at
          this new speed

   
          stepper1.setSpeed(current_speed);

}

  // This will run the stepper at a constant
          speed

stepper1.runSpeed();

}

Example 6: Changing motor speed -

With an Adafruit Motor Shield (v1)

And with an Adafruit Motor Shield V2

Note that the Left, Stop and Right inputs are now back on digital pins 2, 3 and 4 for the V2 shield, as it doesn't need them and so we can use them again.

Example 7: Serial command input

Using stepper motors with RC servo inputs

This page describes a one channel system (running on a chipKIT Fubarino Mini, with a Big Easy Driver) that reads RC servo channel information from a receiver and spins a stepper motor accordingly.