On 07/22/2014 03:19 PM, Dewey Garrett wrote: > > > system latency histogram (jitter) for a 1mS thread: > http://www.panix.com/~dgarrett/stuff/rtai.png > http://www.panix.com/~dgarrett/stuff/rt-preempt.png Well, 50 us jitter on a 1 ms thread is 5%, which is getting to the level it could affect servo stability. All boards in the PPMC family have the ability to trigger the encoder count latch themselves, and then that could be used to trigger the servo thread. If we used that feature, it would reduce the effect of latency jitter to zero, as long as the period was not overrun. Someday, I'd like to work on that....
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