7I90HD with Raspberry pi and getting weird joint 0 following errors

I only see one set of stepgens etc for the X motors in the hal file.

Are sending the output to 2 drives.

the hal-file is not properly commented.

stepgen.00 and stepgen.01 are my X-axis

i have tried also slower rates and they might work better, but i dont understand why the setup is working when "STEPGEN_MAXVEL & STEPGEN_MAXACCEL" is missing in the Joint section with the side-effect is a slow homing

A couple of things:

With a 0.050 mm maximum following error, 250 usec of servo thread jitter will cause a
following error with your current setup . What is you servo thread jitter?

There are a couple of things that can be done to improve stepgen performance with regard to host jitter:

1. Use the stepgen in velocity mode and a PID loop to control the position (use a pncconf created hal/ini file set as a model)

2. Use the DPLL to reduce host servo thread jitter impact on position sampling errors

i set to FERROR = 0.08 and it works. thx a lot

and set MIN_FERROR = 0.02

PCW wrote: A couple of things:

With a 0.050 mm maximum following error, 250 usec of servo thread jitter will cause a
following error with your current setup . What is you servo thread jitter?

There are a couple of things that can be done to improve stepgen performance with regard to host jitter:

1. Use the stepgen in velocity mode and a PID loop to control the position (use a pncconf created hal/ini file set as a model)

2. Use the DPLL to reduce host servo thread jitter impact on position sampling errors

can i make a pid loop in an openloop configuratuion? i thought i need an encoder for that.

Yes, take a look at a pncconf created step/dir hal file.