-420 Query Unterminated on Target Machine

[rkmadse]

On my programming machine, my main station my application is working beautifully. Howerever, when building an application and putting that into an installer my program breaks after installation and running it on the target machine. I am getting the error -1074000000 and it's saying -420 Query Unterminated.. Why would this be occuring on one machine and not another? Why on my comp it works just fine but on the target machine it has this problem? I believe this is the error that occurs when trying to read from an insturment buffer when nothing is within it. I am using the Agilent 3446X plug and play drivers and have been playing with this for two days with no solution. Please help. I can attempt to attach VI's but the project itself is a little too big to tack onto this request.

[FinchTrain]

Hi rkmadse,

A great first step in troubleshooting is going to be making sure that your target machine has all the same software as the host machine. A common cause of this error may occur when you do not have the correct or most updated driver on your machine, or some other subtle difference in software versions exists between the two machines. It may be the case that your host machine has been updated while your target machine has kept the older software versions and drivers. I am assuming you are using LabVIEW, but if you could include more details about your system setup (what software and version) this would help me troubleshoot further.

Take a look to make sure both machines have the correct (and same) driver and software versions running and I'd be glad to continue troubleshooting from there.

Thanks,

FinchTrain

[rkmadse]

Thanks FinchTrain,

I am using Win7 on both machines. The three devices I am attempting to talk to are the following:

• B&K Precision 891 (virtual comport USB)
• Keysight 34465A (USB)
• Keysight B2985A (USB)

My installer is sending over with it (as additional installers) the following:

• NI LabVIEW Runtime 2015 SP1
• NI-488.2 Rimtime 15.5
• NI-Serial Runtime 15.0
• NI-VISA Runtime 15.5
• (I included MAX for configuration of Aliases and troubleshooting)

All my connections to the instrument (in code) are through VISA,, and I think somewhere in there is one of the problems.

A question I haven't found the answer to that may answer this problem is whether each instrument needs a "Driver" installed. I have updated their firmware, and they are showing up properly in Device Manager and in MAX. When I attempt to google drivers for the Keysight instruments all I find are "NI Drivers" (which are just VIs to run the instrument). If there are additional installers for the instruments then I haven't found them. I'll contact Keysight and ask them this question.

Apart from that I believe all other software is the same.

Thanks,

Kellen

[FinchTrain]

Hi Kellen,

To further isolate the issue, run the executable on the host machine to see if the issue lies within the executable. It may be the case that you've already tried this, however, if it works on the host machine, it will likely come down to a driver compatability issue. Another step would be to check the software on each machine in NI MAX. Click on the "Software" tab in NI MAX and verify that the installed software is the same. Again this may be a step you have already tried, but it is important to verify before moving forward.

You can check for instrument drivers on ni.com/downloads. Search for your devices to find relevant driver information.

Keep me posted on your progress.

Thanks,

Eric Finch

[rkmadse]

OK, So I have installed the system on the Host machine and am currently running the executable without any of the same issues. The software comparrison between machines is what is shown below. I believe that all the necessary software for the application to run is already installed.

[rkmadse]

After speaking with Keysight, they believe that there shouldn't be any driver issues. They think that the Error -420 deals with NI-VISA not sending Termination Characters after each command. Does anyone know where that settings is changed? Or is it always done manually within the dirvers?

[billko]

---

@rkmadse wrote:

After speaking with Keysight, they believe that there shouldn't be any driver issues. They think that the Error -420 deals with NI-VISA not sending Termination Characters after each command. Does anyone know where that settings is changed? Or is it always done manually within the dirvers?

---

Keysight (Agilent.HP/whatever the flaovor of the month is) are talking out their... RF port.  "Query Unterminated" has nothing to do with whether a termination was sent or not.  It has to do with sending an incorrect command.  Read this link to see why this error may occur.

edit:

Oops, your first post shows that you probably already know what the -420 SCPI error is.  Sorry.

[billko]

Thinking a bit further on this, maybe you are sending some kind of command that takes some time to process.  It completes in time usually, but on the other machine it does not.  This command may require a *OPC?  Command which turns a command into a query.  VISA will then wait until there is something in the buffer to read.  Check to see if the command that is causing the error is compatible with the *OPC? command.