VISA USB RAW error "VISA: (Hex 0x3FFF0082) The specified object reference is initialized."

[user17625]

VISA  Interactive control USB RAW

Attribute "Interrupt In Pipe Status" has "Invalid Property Value"

with error:  "VISA: (Hex 0x3FFF0082) The specified object reference is uninitialized." 

What does this mean?  What didn't get initialized, and how do I initialize it?

This error was somewhat hidden, and the VISA Interactive Control - Basic IO Tab  seemed to allow me to try to write commands to my Multifunction IO board and with return data stating "no error" but the board is supposed to echo the command back which it wasn't doing. 

[Zach-H]

Generally that error occurs when the VISA close command has nothing to close. This could be because the visa isn't initialized properly (no open VISA command) or because an error was thrown before the VISA close command causing the VISA protocol to close before the VISA close command. Are you using an error handler in your code? If not you may be missing the error which is causing this condition.

As for your missing echo's: Is that in Measurement and Automation Explorer(MAX)? In MAX you have to write and then read from the device to see that kind of an echo. It will say written with no error, but to see anything from the board you need to click read.     

Hopefully that points you in the right direction. I would also recommend checking out and the LabVIEW exapmle for VISA USB RAW. It can be found in the example finder under Hardware Input & Output>>VISA>>USB RAW - Control.vi

[user17625]

No response when sending commands using any or the USB RAW examples, and the data transmission light doesn't blink on the module.  I have been working on this for a good while now and am not making progress, and about to give up on labview.  Is there anyplace I can get phone help to talk me through?

[Zach-H]

Yes, our support line is 1-866-275-6964. If you have standard support contract you'll be routed right through to an applications engineer like myself. 

[mesoscientist]

Is this problem finally solved? I have the same problem like this (the property Interrupt In Pipe Status is invalid) with the NI MAX-generated USB RAW device. So I cannot query it.

[user17625]

I have not gotten past this problem.  Tried many angles.  It is not limited to one specific mfr, as I have tried others and had the same results.  The related project has been shelved indefinitely until (if?) find a way around this. 

[mesoscientist]

If your USB device comes with a proprietary driver and .dll files. It should be possible to interface it with, say, Matlab by loading the dll file into it. That's what I'm trying now. It appears to me that a RAW device may not (you still need to write a whole bunch of stuff if it is registered correctly by NI-MAX) enable all the features of the (no-name) USB device which I could otherwise with a Matlab wrapper.

[user17625]

My USB front end is the Prolific Technology chip PL-2303 IEEE-1284 controller.  The hardware didn't come with any drivers from the mfr but is recognized by windows XP.  Somehow, what was supposed to be a straightforward Labview interface project has turned out to be a brick-wall event. 

[Zach-H]

How are you trying to use that USB to Serial converter? 

It sounds like it just creates a serial COM port for you out of one of your usb ports. Once you install it and it's drivers, you should have a new COM port available which you can select to do serial communication over through programs like Hyperterminal, Putty, or LabVIEW. There is a pretty easy to follow YouTube video here about how to install the device and set up its drivers.

Is that what you're trying to do?

[Dennis_Knutson]

Prolific does in fact make a driver available and it turns the USB connection into a serial port. There is just no reason to be using USB RAW. Where did you get the idea that this is what you should be doing? Surely you did not use the Driver Wizard to create your own inf file for it.