Controlling stepper direction with a button

I'm not very familiar with that library, but apparently speed is supposed to be a positive number and just steps should change between pos and neg.  Also, step is a blocking call, it will step until it is done stepping then return to your code.

Keith Gum wrote:

 

I am trying to control a unipolar stepper with two buttons, one on either side of a salvaged typwriter cage. The sketch will run it one one direction but the

button does not reverse the motor. Thanks for advise.

 

#include <Stepper.h>

Stepper s(20,8,9,10,11);

int button1 = 1;

int button2 = 2;

int buttonState1 = 0;

int buttonState2 = 0;

 

 

void setup()

{

pinMode(1,INPUT); //buttons

pinMode(2,INPUT);

 

pinMode(8,OUTPUT);

pinMode(9,OUTPUT);

pinMode(10,OUTPUT);

pinMode(11,OUTPUT);

 

 

s.setSpeed(500);

s.step(1500); // This is well beyond the max range but I assumed that when the carriage hit the button, it would reverse.   

//delay(5000);

}

 

 

void loop()

{

buttonState1 = digitalRead(button1);

buttonState2 = digitalRead(button2);

 

 

if (buttonState1 == HIGH)

{

s.setSpeed(-500);

s.step(1500);//200

//delay(1000);

}

 

 

if (buttonState2 == HIGH)

{

s.setSpeed(500);

s.step(-1500);

delay(1000);

}

 

 

 

 

}

I tried another approach but the carriage will only move as far as "stepsPerRevolution" will permit. The mechanism must move freely from one button to the next. The far left blue pressure button can be seen in this photo. http://www.flickr.com/photos/50454200@N06/8508893686/

#include <Stepper.h>

int button1 = 1;

int button2 = 2;

int buttonState1 = 0;

int buttonState2 = 0;

const int stepsPerRevolution = 100; 

Stepper myStepper(stepsPerRevolution, 8,9,10,11);           

void setup() {

  pinMode (button1,INPUT);

  pinMode (button2,INPUT);

  // set the speed at 60 rpm:

  myStepper.setSpeed(80);

  myStepper.step(stepsPerRevolution);

  //delay(500);

}

void loop() {

  buttonState1 = digitalRead (button1);

  buttonState2 = digitalRead (button2);

  if(buttonState2 == HIGH)

  {

  // step one revolution  in one direction:

  myStepper.step(stepsPerRevolution);

  //delay(500);

  }

  if (buttonState1 == HIGH)

  {

   // step one revolution in the other direction:

  myStepper.step(-stepsPerRevolution);

  //delay(500);

  }

}

Are you trying to get this to run automatically from side to side using those blue buttons as limits?

Keith

If I'm not mistaken you have a button1 on Pin 1 which is the Tx.

While its possible to use this pin, you should try to leave it available for debugging.

Your photo is not a lot of help to see how you have wired the buttons.

Are you switching 5v onto the pin, or pulling the pin to ground.?

If you are pulling the pin to ground you need to have the pullups activated by adding

digitalWrite (button1, HIGH);

digitalWrite (button2, HIGH);

or use external pullup resistors.

I would suggest shifting the button pins, and adding some debugging output

#include <Stepper.h>

int button1 = 1;

int button2 = 2;

int buttonState1 = 0;

int buttonState2 = 0;

const int stepsPerRevolution = 100; 

Stepper myStepper(stepsPerRevolution, 8,9,10,11);           

void setup() {

  Serial.begin(9600);

  pinMode (button2,INPUT);               //shift to pin 2

  pinMode (button3,INPUT);               //shift to pin 3

  // set the speed at 60 rpm:

  myStepper.setSpeed(80);

  myStepper.step(stepsPerRevolution);

  //delay(500);

}

void loop() {

  buttonState1 = digitalRead (button1);

  buttonState2 = digitalRead (button2);

  if(buttonState2 == HIGH)

  {

      Serial.println("button2 detected");               //add this to see if the button is detected

  // step one revolution  in one direction:

  myStepper.step(stepsPerRevolution);

  //delay(500);

  }

  if (buttonState1 == HIGH)

  {

      Serial.println("button1 detected");            //add this to see if the button is detected

   // step one revolution in the other direction:

  myStepper.step(-stepsPerRevolution);

  //delay(500);

  }

}

mark

Mark,

   When I put the meter to the button pin and press, it goes to 6v. I'll try your sketch this morning. Thanks.

Keith

Mark,

   The buttons will stop the motor, but not reverse it.

Keith

Mark,

     The button is detected until it is pressed, then stops until released.

Keith

The buttons are working if continually press, but I need a momentary switch

to reverse the motor until it hits the opposite switch, etc.

Or you need a relay that activates/deactivates every time a button is pressed?

So the buttons are high when not pressed? 

try these changes.  Be aware that button1 and button2 might be backwards

#include <Stepper.h>

int button1 = 1;

int button2 = 2;

int buttonState1 = 0;

int buttonState2 = 0;

int direction = 0;

const int stepsPerRevolution = 100;

Stepper myStepper(stepsPerRevolution, 8,9,10,11);          

void setup() {

  Serial.begin(9600);

  pinMode (button2,INPUT);               //shift to pin 2

  pinMode (button3,INPUT);               //shift to pin 3

  // set the speed at 60 rpm:

  myStepper.setSpeed(80);

  myStepper.step(stepsPerRevolution);

  //delay(500);

}

void loop() {

  buttonState1 = digitalRead (button1);

  buttonState2 = digitalRead (button2);

   if (direction == 0){

     if (buttonState2 == LOW)

        direction = 1;

     else

         myStepper.step(stepsPerRevolution);    

}

else{

    if (buttonState1 == LOW)

       direction = 0;

     else

myStepper.step(-stepsPerRevolution);    

}

}