Re: [Ext] RE: Help setting up coordinated motions for Galil controller

[Jesse Hopkins via Tech-talk <tech-talk at aps.anl.gov>]

Hi Mark,

Thanks! Based on what I was reading in the optics module docs, it looks like the 2slit.db definitions return the center and gap positions as AOs. We often want to do things like scan the slit center and gap positions/sizes, so I'm assuming the 2slit_soft.vdb definitions would be better, since those provide a soft motor that I could then use with sscan?

All the best.

- Jesse

----
Jesse Hopkins, PhD
Deputy Director
BioCAT, Sector 18
Advanced Photon Source

On Tue, Oct 15, 2024 at 2:02 PM Mark Rivers <rivers at cars.uchicago.edu> wrote:

Hi Jesse,

 

I have not yet started to use the CS motors, so I can’t help with those.

 

We are using the 2slit.db for slits, with template file entries like this:

 

# BMD slits in vacuum

file "$(OPTICS)/db/2slit.db"

{

pattern

{P,      SLIT,    mXp,  mXn}

{13BMD:, BMDV,   m31,   m32}

{13BMD:, BMDH,   m30,   m29}

}

 

Mark

 

 

From: Tech-talk <tech-talk-bounces at aps.anl.gov> On Behalf Of Jesse Hopkins via Tech-talk
Sent: Tuesday, October 15, 2024 1:35 PM
To: EPICS Tech Talk <tech-talk at aps.anl.gov>
Subject: Help setting up coordinated motions for Galil controller

 

Hi folks,

 

At my beamline we're working on switching over to the Galil DMC41x3 controllers for a lot of our basic motion controls. I have a couple of controllers set up, and I'm trying to figure out how to set up coordinated motion, in particular gap and center pseudo motors for a couple of sets of slits (and, eventually, some optics such as monochromator and mirrors).

 

It seems like the most straightforward approach for this would be to use the Galil coordinate system (CS) motors, motors I-P, and define appropriate forward/back transforms for the motors of interest. However, I can't figure out the right way to do those definitions. I defined the basic CS and kinematics as in the GalilTestApp from the git, and as far as I can tell there doesn't seem to be any additional setup that needs to be done on the database side (but I may well be wrong about this). I tried opening the CS motor kinematics window (e.g. "Motor I kinematics", which opens the galil_csmotor_kinematics screen), which provides access to the 8 reverse transforms and one forward transform for that motor, but I can't seem to set the values of the transform. For example, I try to set the motor I forward transform as (A-B)/2 (slit center position) and get the following message:

 

Tue Oct 15 10:54:41 CDT 2024
textEntryValueChanged: Invalid value:
  Name: 18ID_DMC_E04:I_FTRANSFORM_SP
  Value: "(A-B)/2"

 

I've tried various other permutations, such as I=(A-B)/2, or simply just A, for example, and always get the same error message. I also tried using the epics PVs rather than the channel and got the same message. I figure I must be missing something pretty fundamental about how to set this up, and I'm hoping someone can point me in the right direction.

 

I'm running the IOC with the following:

Galil: 4-0-00

motor: 7-3-1

EPICS: 7.0.8

OS: Debian 12

DMC controller firmware: 1.3h

Displays: MEDM

 

 

Another option might be to do this using something like the slit soft motor support in the synApps Optics module. Is this what most people are still doing, or is there another standard approach for this these days?

 

All the best.

- Jesse

 

----
Jesse Hopkins, PhD
Deputy Director
BioCAT, Sector 18
Advanced Photon Source