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Motor record: change HVEL=0 case to default to VELO instead of VBAS - #256

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kmpeters merged 1 commit into
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redomitro:master
Jul 30, 2026
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Motor record: change HVEL=0 case to default to VELO instead of VBAS#256
kmpeters merged 1 commit into
epics-modules:masterfrom
redomitro:master

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@redomitro

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Unsure if this was intended behaviour or not, but I noticed that in the case of HVEL=0 (or the user didn't set HVEL) the record defaults to HVEL=VBAS - this is unexpected behaviour and results in much slower homing than expected.

I've changed motorRecord.cc to instead mirror VELO into HVEL. The modification is tested and functions correctly on a servo controller.

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I suspect this was the intended behavior back when OMS VME stepper motor controllers (which have base velocity commands) were the standard, since it is normally desirable to home at a slower speed. Nowadays, however, there are many controllers that don't have commands for setting the base velocity (microstepping avoids the need for the base velocity) and so this fix seems very reasonable to me.

@kmpeters kmpeters added the bug label Jul 30, 2026
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kmpeters merged commit 47893ed into epics-modules:master Jul 30, 2026
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@kmpeters

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@redomitro, thanks for this pull request!

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