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Instrument (Power Supply) Control with Linux RT in LabVIEW

We are running a project where we have a PXI Chassis, SLSC Chassis and also 5-6 power supplies. Our attempt was to have everything running in the RT headless and then simply pass TCPIP packets back and forth from Host to RT to set the supplies etc. 

 

We have written drivers for the Power Supplies using VISA to open/control the references and while this works fine running interactively in RT, we are not able to control the power supplies yet. We are getting errors even with the IDN? query to the supply on initialization. I did include the .lvlib driver files for the power supplies when building and deploying to the RT so I don't believe that could be the problem. 

 

Are there potential gotchas with trying to control instruments over LAN with LinuxRT? Is this something that isn't allowed in RT? 

 

Any information you may have to help point me in the right direction would be much appreciated. 

 

Keysight Power Supplies, and they are all LAN connected. 

 

Thanks!

 

Kellen

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What kind of error are you getting? Are you using the VIs from the IDnet?

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Applications Engineer | TME Systems
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So we are trying to open a VISA Reference using the standard strings, this works when running Interactively on the RT machine from the host with the following string:

    TCPIP0::192.168.6.9::INSTR

 

However, when I build and deploy this package into a RT application it errors out and fails the basic instrument identification.

 

The Error Returned is: -1074003951 "The ID Query Failed. This may mean that you selected the wrong instrument or your instrument did not respond"

 

Nothing we are doing is too crazy so I'm not sure what it is I'm not understanding. 

 

I am including out driver (.lvlib) in the build. 

 

rkmadse_0-1686431868859.png

 

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After extensive troubleshooting it was found that VISA Server takes about 25 seconds to boot up after the executable VI is running on the system. 

 

Instrument communication on boot doesn't work, but if you continue to attempt to talk to the instrument after 25 seconds it begins to work in a headless configuration. 

 

It seems like nothing should run on the Linux RT until that is booted up so I'm not sure why this is the case, however that is what we have found.

 

Adding a 25 second wait on the front end of our RT program has fixed the issue for now. Kind if disappointing but workable. 

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