LabVIEW Real-Time Application, Problems with Telnet Control over Command Line

[ch.pi3]

Hello everyone,

I have a 2011 LabVIEW program that I've packaged up as a Real-Time Application to deploy on my PXIe-8100 embedded controller. I'd like for the program to run continously, but to only generate a signal (and subsequently collect data) when I command it to do so. To do this, I've developed a 'SCPI' parser/feedback routine within the program that runs in a while-loop, waits for a connection from an external computer, and then allows for two way Telnet communication over command-line once connected. When running the program directly on the PXIe box, this two-way communication system works perfectly. However, when the program is deployed as a RT application, the Telnet communication is not fully functional (only certain commands are received and processed by the program, whereas others are consistently lost or are not processed). When I run the RT application in debug mode, however, everything works perfectly.

The RT application suffers from the same issue regardless of whether the "enable debugging" and/or the "Use LabVIEW 8.x file layout" options are used in the Advanced window of the properties menu.

I'm not sure how much use it will be, but I've attached the program in question to this post (rt_main.vi - my apologies, it's rather large). The 'SCPI parser/Telnet command' component is the leftmost while-loop, as indicated in the attached screenshot. Let me know if there's anything else that might be of use in helping figure out what's going on.

Thank you very much for your insight in advance.

[JGoebel]

Hi ch.pi3,

I have had a little Look at your vi, and the first thought that came to my mind was: Have you checked the Telnet Write/Read VIs for Errors when running it as an executable? I would also concider Timing issues, have you tried using little delays between the Open telnet/write/read?

Best Regards,

Jan Göbel,

Applications Engineer

[JGoebel]

Hi ch.pi3,

I wanted to know if you tried the approaches from my last post. Otherwise I would close this service ticket.

Best Regards,

Jan

[ch.pi3]

Sorry for the delay in getting back to you. It turns out that the reason for this happening was because I was relying on taking values from the VI's front panel, which was not available while the LabVIEW project was deployed on the PXIe-8100 RT target. Hence, the commands that requested front panel values did not work. To circumvent this, I had to create an html remote front panel, which seemed to solve the problem. Thank you for your help, though!