Stepper Motor Consistent Step Size

I recently purchased most of the items from the [ProDriver Hookup Guide. After loading the first example project, I discovered that the step size is not consistent. The motor seems to seize during parts of the motion and results in the overall begin and end positions varying each time the motor moves. Is that normal, or could I have a defective part?](https://learn.sparkfun.com/tutorials/sparkfun-prodriver-hookup-guide/all)

Can you please share a picture of your setup and a video of the operation?

Here is the link to pictures of setup and a video of it in motion: https://photos.app.goo.gl/vLTDh8YtkBuWVDA89

This is with the default Example1_Basic script running (200 step size).

Not seeing a ground connection between the two boards.

Maybe that’s your issue?

That fixed it, thanks! I should have caught that… Recommend changing the [ProDriver Hookup Guide tutorial so that the table in the Input Control Pin Connections section has a Gnd to Gnd connection.](https://learn.sparkfun.com/tutorials/sparkfun-prodriver-hookup-guide/hardware-assembly)

Thank you for pointing that out. It is pictured but not shown in the table below. Thank you.