Trouble Using a Three-Way Switch to Control a Stepper Motor [SOLVED]

Other Hardware Motors, Mechanics, Power and CNC
1

Hello!

I am trying to design a setup that uses a stepper motor and lead screw to move a linear bearing back and forth according to the input of a three-way switch, but I have been encountering problems with wiring in the switch.

I am using an Arduino Uno and Sparkfun's EasyDriver stepper motor controller to control the stepper motor itself.

I wish I could explain in detail what is going wrong, but I really can't get any sort of consistency. It will work how I want it to one minute, and then just start randomly running the motor and stopping the next.

What I'm trying to do with the switch is have it so that when it is flipped left it will rotate the motor one way, when it's flipped right it will rotate it the other way, and when it's in the middle it will stop. I already know that there's going to be something wrong with stopping the motor, but I can't even get it to work correctly when flipping the switch left or right to find out where that problem will be.

I have some proficiency with programming in general (I'm much more familiar with Java than I am with any other language at the moment), but I don't have much experience with circuitry, so I fear that is where my problem may be.

Here's my code:

#include "Arduino.h"

const int posA = 4;     // Position A pin
const int posB = 5;     // Position B pin

int dirpin = 2;
int steppin = 3;


void setup() 
{
// set posA as input
pinMode(posA, INPUT);      
// set posB as input
pinMode(posB, INPUT); 
pinMode(dirpin, OUTPUT);
pinMode(steppin, OUTPUT);
Serial.begin(9600);
}
void loop()
{
int stateA = digitalRead(posA);     // variables for reading the switches status
int stateB = digitalRead(posB);
  if(stateA == HIGH){
    digitalWrite(dirpin, LOW);
    digitalWrite(steppin, LOW); 
    digitalWrite(steppin, HIGH);
    delayMicroseconds(500);
  }
  
  else if(stateB == HIGH){
    digitalWrite(dirpin, HIGH);
    digitalWrite(steppin, LOW);  
    digitalWrite(steppin, HIGH); 
    delayMicroseconds(500);
  }
  else if (stateA == LOW && stateB == LOW){
    digitalWrite(dirpin, LOW);
    digitalWrite(steppin, LOW);
  }
}

Attached is a picture of how everything is wired up:

Any help is appreciated. Thanks!

Arduino Stepper Motor Setup 1.PNG
Arduino Stepper Motor Setup 1.PNG955×716 172 KB

2

Not to be unhelpful but that answer explains it about as well as it can be explained.

Move your orange wire off the 5V connection and onto GND. In your setup(), after setting the pinMode() for posA and posB you then want to digitalWrite(posA, HIGH) and digitalWrite(posB, HIGH) to enable the internal 30K ohm pullup on those inputs. Those pins will then read as HIGH until the switch connects them to GND because the meager current delivered by the internal pullup will be quickly dissipated to GND.

3

Thank you so much! I understand my mistake, and now it turns appropriately based on the switch input. I need to figure out how to turn it off with the middle position now, but at least it's progress! :smiley: