Smart Pin Pulse Mode - Lags

Christof Eb.

Hi,
I am using Smart Pin pulse mode to output a group of 16 microsteps for a step driver.
After starting the pulses, ct1 is set to the new start time of the next group.
After some calculations the cog does waitct1.
Then wxPin, wrPin, and wyPin is set newly, as the speed may have changed.

Typical pulse HIGH length and also LOW length is 15us.
The time lag between after waitct1 and after wyPin is 3.5us.

After several pulse groups however the LOW time is increased to about 45us. It looks as if one full cycle is lost.
As far as I understand I cannot preload the smart pin registers before the group is completely finished?
Perhaps someone has an idea? I have spent some hours on this.
Thanks a lot, Christof