STEPLEN STEPSPACE time for Bergerda AC servo driver

I'm trying to reach 10000mm/min max velocity on three axis, but lowering STEPLEN and STEPSAPECE below 1000 nanoseconds, following error shows up immediately.
Based on driver specs Maximum frequency of input is 1MHZ (Differential motion).

I believe mesa 7i95T isn't limiting factor here!?

My current values:
DIRSETUP          = 200
DIRHOLD            = 200
STEPLEN            = 1000
STEPSPACE       = 1000
SCALE                = 2000

 
 

Are you using 7I95T encoder feedback?

Can you post your hal/ini files?

Reducing the steplength and stepspace parameters
will not directly cause a following error, though reducing them
will allow higher speeds that may expose other limits.

The 7I95T is capable of generating up to 10 MHz step rates

 

Yes I'm using encoder feedback for all axis.

ini & hal files attached

If you will check files, there are JOINT 0,1 and 6 on which I would like to increase velocity.

I would make these changes in the hal file and try again:

Comment out all these (XYZ etc) lines.
That is, change this:

net x-vel-fb hm2_[MESA](BOARD).0.encoder.00.velocity => pid.x.feedback-deriv

to this:

#net x-vel-fb hm2_[MESA](BOARD).0.encoder.00.velocity => pid.x.feedback-deriv

(and so on for y,z etc)

Then add these lines:

setp hm2_[MESA](BOARD).0.dpll.01.timer-us -200
setp hm2_[MESA](BOARD).0.encoder.timer-number 1
setp hm2_[MESA](BOARD).0.stepgen.timer-number 1
setp hm2_[MESA](BOARD).0.encoder.sample-frequency 20000000

 

setp hm2_[MESA](BOARD).0.encoder.sample-frequency 20000000 gives me error on startup (pin not exist).

So I tried with:
setp hm2_[MESA](BOARD).0.encoder.muxed-sample-frequency 20000000

but result is same, when lowering STEPLEN and STEPSPACE from 1000 to 800, immediate following error.

A have also attached my hal_load file to check

You may have to increase the following error limits a bit and plot the
commanded and feedback positions and joint following error with halscope
to determine why you are getting a following error:

Possibilities:

Drive does not work with shorter step signals

Encoder feedback does not work at higher speeds

Instability/tuning issues


 

Scope reading with 1000 nanoseconds:
 

And with 900 nanoseconds and increased following error:
 

Looks like the drive is not responding to shorter step pulses (no motion at all)

Is is possible there is a digital filter in the drive so it rejects shorter than 1000 ns step pulses?

Driver manual can be downloaded here: en.bergerda.com/download/31.html

I checked, there is parameter P82 - Input pulse filter frequency, which default value by manual is 800, but need to check tomorrow what number is actually set!

 
 

Parameter 82 did the trick! It was set to 600 by default, now I set it to 1000, and works perfectly up to 170mm/s velocity.