Re: MAXnet Alarm State Under High Motor Command Load

[Mrinal Bera via Tech-talk <tech-talk at aps.anl.gov>]

Hi Kevin,

We are getting the “Controller Error” before just finishing the motion of an axis using MAXnet controller and the following message is now printed on the IOC screen:

omsBaseDriver:getAxesArray:MAXnet1: array string conversion error, count: 2, axes: 8, input: >0 00000002<

Also, we noticed that all the moving flag of the axes of the SPC controller turned ON momentarily before the end of the motion when we get the “Controller Error”.

Is this a driver or controller issue?

Thanks,

Mrinal

From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Jiajun Tian via Tech-talk <tech-talk at aps.anl.gov>
Date: Monday, March 9, 2026 at 11:53 AM
To: Peterson, Kevin M. <kmpeters at anl.gov>, tech-talk at aps.anl.gov <tech-talk at aps.anl.gov>
Subject: Re: MAXnet Alarm State Under High Motor Command Load

Hi Kevin,

Thanks for your help. Following the error message, we determined that the issue was related to the driver. We were using a newer model ACS driver with a relatively old motor, which caused the incompatibility. After switching to the appropriate driver, the problem was resolved.

Best,
Jiajun

Jiajun Tian, Ph.D.

Postdoctoral Researcher

NSF’s ChemMatCARS, Pritzker School of Molecular Engineering

University of Chicago

9700 S Cass Ave Bldg 434D

Lemont, IL-60439

United States

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From: Peterson, Kevin M. <kmpeters at anl.gov>
Sent: Wednesday, February 11, 2026 4:04 PM
To: Jiajun Tian <jiajtian at uchicago.edu>; tech-talk at aps.anl.gov <tech-talk at aps.anl.gov>
Subject: Re: MAXnet Alarm State Under High Motor Command Load

 

If you uncomment the USR_CXXFLAGS line from omsAsynApp/srcMakfile:

https://urldefense.com/v3/__https://github.com/epics-motor/motorOmsAsyn/blob/c0ae4c740d699e64f264ce6f53f23a492abf19fa/omsAsynApp/src/Makefile*L8__;Iw!!BpyFHLRN4TMTrA!-omSqwr9ZTVcKOxtXsinkdQPcCcC6h-UC2glC45EocFBoWFuWBrMJaZYjzkrj5AMhDLh8xRDh5Bc6XqgXl_wrA$

and uncomment the motorOMSBASEdebug variable in omsAsynMAXnetSupport.dbd:

https://urldefense.com/v3/__https://github.com/epics-motor/motorOmsAsyn/blob/c0ae4c740d699e64f264ce6f53f23a492abf19fa/omsAsynApp/src/omsAsynMAXnetSupport.dbd*L2__;Iw!!BpyFHLRN4TMTrA!-omSqwr9ZTVcKOxtXsinkdQPcCcC6h-UC2glC45EocFBoWFuWBrMJaZYjzkrj5AMhDLh8xRDh5Bc6Xq91hlH6Q$

and rebuild motorOmsAsyn and the IOC, you should then be able to set the variable on the IOC's shell:

var("motorOMSBASEdebug", 4)

which should result in a "setting Problem flag" message being printed.

Kevin