Advanced Search

I wonder, is there a Raspberry HAT that can direct interface with a stepper driver ?

Thanks
Jonh.

I'm using a Raspberry Pi 4 to drive a Mesa 7i96.   For unknown (as yet) reasons, I can't reliably run without errors unless I bump SERVO_PERIOD to 2000000 (i.e., 2ms).

What affect will this have on machine operation?  I sort of understand what's scheduled to run in the base thread, which of course is largely (completely?) irrelevant now that I have the Mesa.  But I don't have a good mental model for what runs in the servo thread, so I don't have a good understanding of what happens to operation/performance if it only runs half as often as usual.  Where would the difference show up?

Until recently my mill maxed out at about 40ipm, so absolute performance wasn't really a consideration.  I've upgraded to a machine capable of at least 80ipm using Grbl, and initial tests with LinuxCNC and the Mesa card indicate 100ipm may be fine.  So now I'm wondering if I need to start worrying more about that servo thread.

paul

Yes, it seems like some encoder option is not set correctly.
Clearing the count on every index really makes no sense for
general encoder use.

I don't really know but it seems to be set in the ini file:

 

It works. Thank you.

Thanks, PCW for this example! I try this out the next days. 
or2 is not used actually. 3D is NO and WZL is NC, otherwise I would have put them both in series.
I will see if I have to delete the -not for the 3D switch.
Thanks a lot and have a nice weekend!
Hanno