is freqmode alway's the smoother option?

[Jacob Kranendonk <j_kranendonk-at-yahoo.com>]

Hi list,

I use high resolution steppermotors 600 step/rev.
combined with 1/8 microstepping(total 4800step/rev.
Therefore I have VERY smooth motion in steppermode,
low and high speed. In freqmode however, I have smooth
motion at low speeds and very rough motion at high
speeds(+/- 10-20Khz). I changed quite intensly PID,
FF, output_scale and servo calculations cycle_time
settings after reading the latest manual, but motion
stay’s rough at high speeds! Only if put P to 0 motion
becomes smooth at high speeds, however I couldn’t get
EMC to work correctly at all this way. Could it be
possible that in my case (high resolution
steppermotors combined with microstepping and high
steprates) freqmode isn’t the smoothest option???

PS test have been done with a 1.1Ghz cpu with freqmode
base task period of 0.000010

Thanks in advance, Jacob


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