Laser Harp Code Conversion

On one the forums that I help with, a member was asking about converting a Frameless Laser Harp from using a Unipolar Stepper motor to a Bipolar Stepper Motor.

After a few bouts on the forum explaining things I decided it would make a good video and others would be interested with the final solution and code

So here it is.

This is not designed to be a detailed explanation on how stepper motors work, just a high level description and loads of detail on how the code was converted and massively simplified

I have not tested the code with a Laser or actual stepper as I don’t have the controller that the code expects but I did include a diagnostics session using my MDO3000 Oscilloscope to validate the code was outputting the right signals and the timing was ok. So it should be good to go

The original Laser Harp project is here on Instructables http://www.instructables.com/id/Frameless-Laser-Harp/?ALLSTEPS

the forum thread can be found here:- http://www.element14.com/community/thread/47546/l/stepper-motor-wiring-helpand-a-few-other-small-questions-from-an-instructable

The stepper used for the new version was this one: - https://www.sparkfun.com/products/10551?gclid=Cj0KEQiApruyBRCFqoDu1pbk9rkBEiQAF8EFdVmEBorGt6koPmFkaibEpRmZ94Z6r8BWhmTqALtYiMYaAv1c8P8HAQ

The driver from Texas Instruments 754410 is here: - http://www.ti.com/lit/ds/symlink/sn754410.pdf
The code will be posted in the next day or two as I need to write up the other posts to go with this

At the end of the day this is a classic example of where code is written by a beginner (And it works ok so no criticism there) but then can be re-worked to me way more streamlined and easier to maintain

I hope you find it useful, even simply as an example of code refactoring,

I may actually go try to build this thing...