Experimental Physics and
Industrial Control System

"Gregory, Ray via Tech-talk" <tech-talk at aps.anl.gov> · Tue, 3 Oct 2023 14:31:59 +0000

Kevin,

I am interested in preventing a user or client from changing the commanded position of the motor. By disabling, I am referring to more aggressive actions, such as removing torque or drive power. I want the motor to still be powered and its position controlled.

Thanks,

Ray

Ray Gregory
Oak Ridge National Laboratory

-----Original Message-----
From: Kevin Peterson <kmpeters at anl.gov> 
Sent: Tuesday, October 03, 2023 9:17 AM
To: Gregory, Ray <gregoryrd at ornl.gov>; tech-talk at aps.anl.gov
Subject: [EXTERNAL] Re: preventing changing an EPICS motor's commanded position

Ray,

Can you provide more details about what "disabling the axis" means?  The 
behavior of the motor record's CNEN field, which is labeled "Torque" on 
the motorx_all screen, is controller dependent; for some controllers 
CNEN enables/disables drive power, for other controllers CNEN switches 
between open and closed loop control, and some drivers do nothing when 
CNEN is changed.

Kevin

On 10/2/23 12:32, Gregory, Ray via Tech-talk wrote:
> Hi,
> 
> How can I prevent changing an EPICS motor record’s commanded position 
> (.VAL field) without disabling the axis?
> 
> Thank you,
> 
> Ray
> 
> Ray Gregory
> 
> Oak Ridge National Laboratory
> 

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System