@robotbuilder Yes they do run simultaneously. I used similar code. If you see the video you will see the problem.

@zander My only options are 4K and HD on my iPhone. My last link should now be OK. Please let me know

@zander @will this link should work

@zander First time video on iPhone. Options are 4K or HD each each with 24 or 30 or 60 options. What is 4K 24?

@will Sorry. I assumed you had seen the video. I am fixing it. I will send another link so you will have a better perspective.

@inq Good advice, thanks. In your absence I posted a cleaned up version of my sketch along with a link to a video showing the latest problem.

@will Thank you, that looked promising but there was no reaction. The steppers didn't blink and kept running. By the way, did the video link work O...

@will The problem is in Case: 3. the yoyo function. The video shows the problem when the yellow LED lights up. The two stepper statements are ar...

@will I am currently looking at drop box. Never used it but I believe I will be able to get a URL.

I have ironed out most of the bugs and have a video showing exactly what the problem is. Unfortunately it is too big to post here. (40Meg) Is there an...

@will Thank you. I will explain the peculiar movement and try to explain clearly what I am trying to do tomorrow. I have to go now. Also thank you @in...

Thank you @will. Very good point and may be one of the movement problems. I moved it to stepper 2 but still getting peculiar movement so I need to tak...

@will Wow that is an interesting analysis. int x = 0 is the initiation of the While loop that runs the steppers. I didn't capture x = 0 in the switc...

@will You are right again. Thank you.

****Error***** didn't show. The line is under switch..... Case 1 starts setStepper.