Stepper Overheating

hi,
i've got arduino uno , trying use power stepper motor. when try stepper overheats.

http://www.schmalzhaus.com/easydriver/examples/example1_bb.png

the code using is:
int distance = 0;

void setup() {               
  pinmode(8, output);     
  pinmode(9, output);
  digitalwrite(8, low);
  digitalwrite(9, low);
}

void loop() {
  digitalwrite(9, high);
  delaymicroseconds(100);         
  digitalwrite(9, low);
  delaymicroseconds(100);
  distance = distance + 1;
  if (distance == 3600)
  {
    if (digitalread( == low)
    {
      digitalwrite(8, high);
    }
    else
    {
      digitalwrite(8, low);
    }
    distance = 0;
    delay(500);
  }
}

the problem supplying high voltage/current motor.

when motor powered there current flowing through windings , appear voltage of motor supply id high.

stepper motors tend warm when stationary.

Arduino Forum > Using Arduino > Motors, Mechanics, and Power (Moderator: fabioc84) > Stepper Overheating

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