Limit Switch output IoniCube


I have a question about the Limit Switch output of the IoniCube.

i have a cube setup with 3 pro servo drives in it and it is wired up and functional.

From my understanding the GPO4 or Limit switch output should be high when the limit witch of the axis is pressed. Though measuring directly on the pin does not show any change in voltage or continuity to ground.

i can see that the GPI1 (homing switch input) is being activated and the drive acknowledges that it is homed.It just doesn’t trigger the limit output pin.

Is my understanding wrong or is there a software problem?
(running the latest firmware)

Best Regard
Tobias T. Strate


I have the same problem. I also made sure that all the posible limit inputs GPI1, GPI2 and GPI3 were all pulled low and that the indicator in the Granity software tool reflected this. Still no change in GPO4_X, GPO_Y.

Perhaps there is a flag that must be set to reflect the inputs of the limit switches on the outputs?

Perhaps these need to be used as “open collector” outputs with a common high that these outputs pull low?

Any luck figuring this out?


Maybe @Tero has some thoughts about this?



GPO4 will be high if both of “Pos feed enable” and “Neg feed enable” as seen in Granity status are true. These Pos/Neg feed enable states are affected by parameter LSP (Limit switch polarity). If you see both feed enables being false, then you probably need to invert the switches with LSP parameter.

I hope this helps!


Inspired by the question, I improved the specs here:


To make sure I understand “Pos feed enable” and “Neg feed enable” are GPI2 and GPI3, correct?

When I change the LSP from “Logic high when overtravel” to logic low when overtravel it does not change the actual input states (normally low for my limit switches in this hardware), it just changes how it interprets the states.

Because my hardware is normally low I can’t physically get a condition where GPI2 and GPI3 are high so I can never trigger GPO4, correct?