easy driver jitters

hi all

i'm trying to control 3 steppers with 3 big easy drivers from an Arduino Uno. with one driver and one stepper all was going fine, using the AccelStepper library to give me acceleration and (seemingly) easy addressing of multiple motors.

however, having hooked up a second driver and second motor i'm getting all sorts of weird jittery results, inconsistent speeds, stopping and starting, etc.

i have pulled MS2 and MS3 low to give me half-stepping, which i read would help, but no good news with that. i have both drivers using common ground and common power, and both steppers using a common ground on the arduino.

the code i'm using is a butchered example from the AccelStepper page.

andy pointers?

thanks

#include <AccelStepper.h>

AccelStepper stepper1(1, 9, 8);
AccelStepper stepper2(1, 7, 6);

void setup()
{  
  
   pinMode(4, OUTPUT);       //MS3 - stepper2
   digitalWrite(4, LOW);
   pinMode(5, OUTPUT);       //MS2 - stepper2
   digitalWrite(5, LOW);
   pinMode(10, OUTPUT);       //MS3 - stepper1
   digitalWrite(10, LOW);
   pinMode(11, OUTPUT);       //MS2 - stepper1
   digitalWrite(11, LOW);
  
   
   pinMode(8, OUTPUT);       //direction
   digitalWrite(8, HIGH);
   pinMode(9, OUTPUT); 
   digitalWrite(9, HIGH);
   pinMode(6, OUTPUT);       //direction
   digitalWrite(6, HIGH);
   pinMode(7, OUTPUT); 
   digitalWrite(7, HIGH);
   
   stepper1.setMaxSpeed(650);
   stepper1.setAcceleration(800); 
   //stepper.setSpeed(1000); 

   stepper1.moveTo(5000);
   
   stepper2.setMaxSpeed(400);
   stepper2.setAcceleration(800); 
   //stepper.setSpeed(1000); 

   stepper2.moveTo(5000);
}

void loop()
{  
  digitalWrite(8, HIGH);
   stepper1.run();
  
  digitalWrite(6, HIGH);
   stepper2.run();
}

as a reminder to myself, and as a reminder to others who might be as absent minders as i am. before writing in to the forum, check that you have switched out the 1A power supply you were using for testing one motor and have connected the 6A supply you had for working with multiple motors.

hope this is of some use to someone...

:-[

blamski:
as a reminder to myself, and as a reminder to others who might be as absent minders as i am. before writing in to the forum, check that you have switched out the 1A power supply you were using for testing one motor and have connected the 6A supply you had for working with multiple motors.

Does this mean the problem has gone away?

It is a very easy mistake to make.

...R

yes, the 'problem' is now fixed. thanks! the stupid thing was that i was just advising someone on another board to check his current supply to fix his odd servo behaviours...