FTP Error 426 in Main Page of VeriStand Custom Devices

[Poolean]

Hello all,

The LabVIEW Intermediate FTP VIs work as expected in the development environment, but they throw errors and warnings and hang when used in a VeriStand Custom device. Attached is a simple custom device, which can be used to reproduce the problem. There are folders containing the built devices and a VeriStand Project already containing the custom device.

Steps to reproduce:

1. Setup a hardware target running the VeriStand Startup EXE.
2. Place a couple of .txt files at the following directory on the Target: c:\ni-rt\LabVIEW Data\
3. Run the RT_GetFileList.vi included in the LabVIEW Project.
4. Notice that this VI executes successfully and returns the names of the text files moved to the target in step 2.
5. Enter the target's IP address in the VeriStand System Definition file.
6. Open the Main Page of the custom device in VeriStand by clicking on it.
7. VeriStand hangs for about a minute due to a FTP timeout as soon as the custom device is selected and no file names are returned from the target.

Error Text

426 Connection timed out

NI_FTP.lvlib:FTP Open Data Connection.vi:4490009->NI_FTP.lvlib:FTP Data Receive.vi:3680008->NI_FTP.lvlib:FTP [LIST].vi:1520002->NI_FTP.lvlib:FTP Directory Listing.vi:240001->RT_GetFileList.vi->Custom Device FTP Bug Custom Device.lvlib:Custom Device FTP Bug Main Page.vi->

Any suggestions for a fix or a work-around would be much appreciated! 🙂

Mike

[Tepig]

I guess you have already understood why you were seeing the behavior.

As Andy described, you cannot execute both LabVIEW and VeriStand simultaneously on single PXI RT Controller.

When you execute the VI during you are executing VeriStand project, VeriStand engine would be stopped. Because of this step, System Def File would be hang.

[Poolean]

Hi Emboar,

The VI calling the FTP VIs is located on the block diagram of the Main Page of the VeriStand Custom Device. Therefore, it is called when someone clicks on the Custom Device tree entry in VeriStand. This is when VeriStand then hangs and this VI throws an error.

To be clear, I'm not executing this VI simultaneously with VeriStand. I only executed it separately in the development environment to verify that it functions properly, which it does.

You're right in that if this VI called from the development environment and the VeriStand engine is already running, the engine will be stopped. If you wanted to then run a VeriStand project, you'd have to change the startup INI on the target to start the VeriStand startup EXE as it was doing previously.

Also, who did you mean by referencing "Andy"? When I look at this thread, you're the only person who's responded.

Mike

[Tepig]

opps.... Im sorry : ( I think I got burned out from daily hard work.

I will check your post again.

[Joel-P]

Hey Mike,

I tested this on VS 2017 and it worked just fine. Not sure how much that helps.

It's interesting that it works fine in LV, but not in VS. Have you tried setting up a different FTP server, e.g. Filezilla, on some other computer in the office and then using that IP for the VS Controller to try and pull a file list? If that works, then it's probably an issue with the PXI target. If it doesn't work, then it might be a firewall exceptions issue for VeriStand, since FTP operates on a different port than the typically VS deploy and communications. It could be that the firewall is blocking port (21) for VS and not LV.

What about Software on the target PXI, is the Legacy FTP server installed? I remember that being a thing, but don't know how it would affect this. You could also try setting a username and password on the target, "admin" "admin", I know on some of our later targets some stuff was locked out unless you have a non-blank password.

Anyway, those are my quick thoughts.

Cheers,

Joel

[Poolean]

Howdy there Joel!

Thanks for testing this. It could just be the target I'm using. I'll try out another PC or PXI sometime this week. And thanks for the addition suggestions as well. I'll give them a shot too and let you know how they go.

Stay beautiful,

Mike

[Poolean]

Emboar, np. We've all been there! 😉