I'm attempting to simply move a small stepper motor over GPIO using a Sparkfun Easy Driver. This Stepper motor is the one I'm attempting to use. I'm using similar code and configuration to that shown in this video. The motor does move in response, but only oscillates in place. Is this because I have a four phase motor hooked up like a bipolar, is it because the raspberry pi isn't putting out enough amperage, or is this a danger of using a pwm input.