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Actually all LinuxCNC stepgens run in velocity mode. The velocity is typically
calculated with dp/dt (rate change of position). When index is detected, this causes
a step in the position (position is zeroed on index detection). The step will cause a large
bogus velocity calculation in position mode stepgens. This is bounded by the stepgen
acceleration bound so not huge but definitely will generate a detectable motion glitch.

In velocity mode, this is worked around by the fact that the PID component has an index-enable
input, so can work around this issue (by skipping the velocity calculation for the position step).

It would be possible to fix this issue in the position mode, but since in general, velocity mode works better
it has not been addressed.

Overall these issues show that LinuxCNCs index handling needs reworking, The encoder position should really
not be cleared (unless the hardware has no other option) , as it creates the need for all these ugly work-arounds
and in fact the index position offset should be applied at a higher level and not at the low (hal control loop) level

But its open loop... i was thinking velocity mode is for closed loop.

Türkçe is the right 

Install?
sudo apt update
sudo apt install freecad

Oder die gcode von FreeCAD zum LinuxCNC senden?

"
Also stepgen position mode should work but it will have a glitch at index detection. "
Can you please explain what kind of gitch this is?

Thanks again, it worked!

Hat geklappt!

DANKE!

Thanks a lot! I will try that later on!

I'm a little ashamed because i have read that in the manual but did not remember...

Hallo,

wie kann ich freecad 1.0 in linuxcnc debian einbinden?

hilfe wäre gut

karlhe

Thanks for the help pippin88. All config files are attached.

All I/O pins on the 7I92[X] start up in input mode and remain there until
LinuxCNC starts. They change back to input mode when LinuxCNC exits
(or the watchdog bites)

The PIN state when in input mode is determined by pullup/pulldown resistors
on the I/O pins. Pullup or pulldown mode is selected by jumpers W1 and W2 on
the 7I92T[X] W1 controls the mode of P1 and W2 controls the mode of P2.
When the jumper is in the "UP" position, pullup mode (the default) is selected. When
the jumper is in the "DOWN" position, pulldown mode is selected.

I suspect you want to select pulldown mode on P2.

I should note that pulldown mode does not work with all breakout boards
as some require pullups because they have bare  open collector Optocoupler
outputs.

 

If this is an issue with the probe input, did you first check that
motion.probe-input changes as expected when your sensor is activated?

(check with halshow's "WATCH" tab)

  

I would test this by hand by watching  index.n.enable with halshow
and then:

sets index.n.enable true

(in halshow or with halcmd)

and seeing if toggling the hardware stepgen index pin clears  index.n.enable
You might also verify that the GPIO pin associated with the stepgen index
changes when you toggle the stepgen index pin.

note: index.n.enable is the name of your signal that connects the joint
index enable to the stepgen index enable.

Also stepgen position mode should work but it will have a glitch at index detection.
The more standard stepgen velocity mode is better as it handles the stepgen position
jump at index detection better.
 

So hoffe das Die beiden Files  angekommen sind.
Vielleicht nimmt sich einer die Zeit und schaut sie an.
Gruß Hans

Ich weiss nicht wieso es nicht geht?

Hat schon wieder was nicht Funktioniert