VISA Serial Connectivity Issue (invalid property node?)

[PFour]

I am using two Sparkfun FTDI Basic breakout boards to send receive data via UART. Yesterday, everything seemed to be working fine and I was successfully transmitting and receiving. Today, I changed a few minor and irrelevant things in my code, briefly had the USBs unplugged, and now it suddenly seems to be saying 'no thanks' and not cooperating.

I've read through the various similar discussion forum posts, however, it seems that while this is a somewhat common issue, the solution is heavily dependent on the device(s) being used. 

When I open NI-MAX and create a test panel for one of these devices, I am able to write the default data (*IDN?\n) but as soon as I try to read status bye or read the data I get the following error messages.

1. Read STB Operation
Error

VISA: (Hex 0xBFFF003A) Unable to start operation because setup is invalid (due to attributes being set to an inconsistent state).

2. Read Operation
Error

VISA: (Hex 0xBFFF0015) Timeout expired before operation completed.

It looks like the device attribute "is port connected" is an invalid property node. Perhaps this is because it is not an NI-serial device? Does anyone have any suggestions for how I can eliminate this property node both in NI-MAX and in my VI? Unfortunately, the VISA configure function does not contain an input for "is port connected" which begs the question as to how one can delete dependency for this device attribute. 

At this point, my troubleshooting has consisted of trying out some of the other USB ports on my USB hub. I've also verified that the 'COM' port that windows is using for the device matches up with the COM port that NI-MAX is assigning. 

Thanks for the help

[arteitle]

Did the COM port number assigned to the FTDI chip change when it was unplugged and replugged? Also, is whatever's at the other end of the serial line programmed to respond to "*IDN?"?

Edit: I've just read that the "Is port connected?" property only works with NI's devices, so you shouldn't expect an accurate result from it.

[PFour]

I was able to get it working again... although I'm not quite sure how. Tried various different ports and finally had some luck. At the peak of the frustration, the exact same bit of code was functioning correctly in one vi, but was error-ing out in another. I'll add another comment if I'm able to figure out what happened with the mixup. 

[D.Y]

Hey!

I have the same issues. My VI is not working because of an invalid property node and I have the following errors displayed at NI VISA Test Panel:

1. Read Operation: VISA (Hex 0xBFFF0015)

2. Read STB Operation: VISA (Hex 0xBFFF003A)

Do you have a specific solution for this?

Thank you in advance!

D.Y

[arteitle]

What is the invalid property node?

[crossrulz]

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@D.Y wrote:

I have the same issues. My VI is not working because of an invalid property node and I have the following errors displayed at NI VISA Test Panel:

1. Read Operation: VISA (Hex 0xBFFF0015)

2. Read STB Operation: VISA (Hex 0xBFFF003A)

---

Since you are getting this in the VISA Test Panel (ie, using MAX), we can ignore any LabVIEW interaction.  So if you are getting a timeout error, that implies you are sending the wrong command.  What are you trying to communicate with (what instrument)?  What command are you sending?

[D.Y]

I try to communicate with a P7000 Series Stepper Drive (Stepper Motor Type: T23NRLC; Stepper Drive: P70360). We have a cRIO-9074 with the integrated modules NI-9222, NI-9411 and NI-9512.

First of all I have defined a "Motion Handle in" and set it into "Configuration mode" with the Set Scan Engine Mode.vi. Everything works fine until then. After I try to set a Property Node (with Axis Feedback Source, Axis Velocity Threshold, Enable Home Switch, Position Loop) an Error -70233 pops up. The Stepper Motor can´t switch to "Active Mode".

[D.Y]

Addendum: I sent the default *IDN?\n command through VISA Test Panel.

[arteitle]

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@D.Y wrote:

I try to communicate with a P7000 Series Stepper Drive (Stepper Motor Type: T23NRLC; Stepper Drive: P70360). We have a cRIO-9074 with the integrated modules NI-9222, NI-9411 and NI-9512.

First of all I have defined a "Motion Handle in" and set it into "Configuration mode" with the Set Scan Engine Mode.vi. Everything works fine until then. After I try to set a Property Node (with Axis Feedback Source, Axis Velocity Threshold, Enable Home Switch, Position Loop) an Error -70233 pops up. The Stepper Motor can´t switch to "Active Mode".

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Error -70233 apparently indicates "NIMC_resourceNotFound" with description "The specified resource was not found." Can you pinpoint what subVI specifically is generating that error, before it "pops up"? Can you share your code with us?

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@D.Y wrote:

Addendum: I sent the default *IDN?\n command through VISA Test Panel.

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That command will only elicit a response from equipment that supports the SCPI standard, which a stepper drive isn't likely to. Do you have any documentation for your stepper drive that tells you how to communicate with it?