Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Thu, 15 Mar 2018 17:11:39 +0000

You have a 32-bit dynamic range to work with.  So you need to decide units that the motor record will use e.g. nV  and set MRES to give you the best resolution you can get without overflowing 32-bits if the current is too high. Your driver will scale back from the motor integer units to device units.

Mark

> -----Original Message-----
> From: Sobhani, Bayan [mailto:[email protected]]
> Sent: Thursday, March 15, 2018 12:01 PM
> To: Kevin Peterson <[email protected]>; Mark Rivers <[email protected]>; tech-
> [email protected]
> Subject: RE: Motor Record not moving distances less than .5
> 
> My problem is I am not working with an actual motor that works with counts but a
> SourceMeter which reads and writes floating point values. I could set MRES to a very small
> number, but I may lose some range or resolution since this device measures in the femtovolts
> and Motor Record uses only a 32-bit integer to store position. Maybe I should not have used
> motor record for this task (it works very nicely otherwise though).
> 
> Alex
> 
> -----Original Message-----
> From: Kevin Peterson [mailto:[email protected]]
> Sent: Thursday, March 15, 2018 12:51 PM
> To: Mark Rivers <[email protected]>; Sobhani, Bayan <[email protected]>; tech-
> [email protected]
> Subject: Re: Motor Record not moving distances less than .5
> 
> On 03/15/2018 11:48 AM, Mark Rivers wrote:
> > If not don't worry about ERES or UEIP, and just set MRES to 1/(steps per engineering
> unit).
> 
> Or leave the MRES at 1 and work in units of steps.
> 
> Kevin

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System