i have some stepper motors that i m trying to run with an adafruit motor shield but they just vibrate
I am powering them using the barrel jack on the arduino
I thought that with bipolar it didn't matter
You are kidding yourself if you think the Arduino can POWER a stepper motor.The coils on a stepper motor must be excited in the proper order.
my steppers are tiny and require little power and you were right about the wiring