On Fri, Jun 11, 2021 at 04:28 PM, Otto wrote:

What if you set your driver jumpers to match BOTH the SLEW and GOTO microstepping values? Forget about on-the-fly switching. I would set them to 16 or 32 all around (preferably 16 for a bit faster slew/GOTO test).

The STM32 does not have jumpers for microstepping on Axis1 or Axis2.
It is done in Config.h, so OnStep controls that.

Second, in your video, your phone shows your local time as GMT-8 (or UTC-8).  From your coordinates you are in the Seattle area?  If so, current offset is 7 hours, not 8, assuming you are in DST.  I observed a similar phenomenon when I first tested my installation.  I forget exactly what I did to force the UTC offset to the correct value.  I have only used OnStep a few times, but I think I had to enter the UTC offset manually.

One thing I have noticed is that you press Upload, but never Use Current.
The procedure is to first press Use Current, which updates the screen with the GPS location.
Then press Upload to send that to OnStep.

But you seem to have done that in a previous session anyway, and you don't need to update the location every again unless you travel with the mount to another location.

Your calculations are correct, based on what you listed earlier (pulley sizes, and so on).

Again: you said it undershoots, but the video shows it is overshooting.