Re: read RVB and VAL don't match when moving smarAct motors without encoders

[Juliane Reinhardt via Tech-talk <tech-talk at aps.anl.gov>]

Hi Kevin,

thanks for your reply. I'm not sure what you mean by GST, GA or GP 
commands. However, we tried to communicate with the smarAct motors via 
the vendor software and did not get very informative feedback. (Same 
return value no matter what motor/controller we were using) Is there a 
way to get for feedback in EPICS, like a debug mode?

Best,
Juliane

On 11/11/20 16:05, Peterson, Kevin M. wrote:
> Juliane,
>
> How does the MCS controller respond to the GST, GA and GP commands for
> an axis without an encoder?  It should be possible to send them using an
> asyn record or a terminal in the vendor software.
>
> The MCS driver assumes every axis will have a sensor and sets the motor
> record's problem bit if the GST command returns an error.
>
> Kevin
>
> On 11/11/20 4:14 PM, Juliane Reinhardt via Tech-talk wrote:
> > Dear EPICS team,
> >
> > I have recently been setting up smarAct MCS controllers for a couple of
> > smarAct motors, some of them have encoders and some don't. The 2 motors
> > that don't have encoders don't move although they are connected properly
> > (I assume). When I do "caput motor.VAL 0.5" I get the feedback for old
> > and new VAL and when I check with "caget motor.VAL" it matches. However,
> > the actual "caget motor.RBV" does not change accordingly and the motor
> > did not move.
> >
> > What is required to move motors without an encoder in this case?
> >
> > Thanks,
> > Juliane

--
Juliane Reinhardt, PhD
Project Scientist | ALS Computing Group
Blg. 15-337E | phone: 510-486-4313
jreinhardt at lbl.gov
Lawrence Berkeley National Lab