Backlash Settings: Zero when Disabled?

[RSI 8.3.1]

Backlash Settings only Queryable while Enabled ?

Should I expect the backlash parameters set with

not to be queryable when the drive is disabled?

My use of

Returns 0 for both while the drive while the drive is disabled but returns the values I gave it when the drive is enabled.
I found this counterintuitive, (especially since I can set the parameters while the drive is disabled, but I cannot verify that they’ve been set without enabling), but just so that I have informed expectations, is this expected behavior. The docs point out that backlash doesn’t use PUUs (which I assume doesn’t mean that it “ignores” position factor—because that’s used by the drive natively, right?), but nothing about the need to enable the drive to query the settings.


The “Backlash Compensation - Docs” page has a small typo: In the “RapidCode API Usage” section, “BacklashRetSet” is mentioned twice, once when “BacklashRateGet” seems intended.

Also, the docs for the specific backlash APIs have “See Also” links. Could I suggest that each of these link at least to the analagous get/set action for the same parameter and the same action for the “sister” parameter? If I wanted to move around to all the backlash API’s, I can’t do it without going back to search results, the entire Axis API, or the backlash topic doc.

This is expected behavior. The rate and width are overwritten to 0 while the axis is disabled to make sure no offsets are applied while the axis is idle. I understand that make is a bit difficult to verify it has been set correctly.

I’m not sure what you mean by PUU. Do you mean UserUnits ? That is correct that this feature uses drive counts an not UserUnits.

Thanks for the documentation feedback. I agree it can be a bit hard to navigate at times and we will work on improving navigability.

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