Instrument Control (GPIB, Serial, VISA, IVI)

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How to decrease default timeout for VISA Open?

I have a basic vi that just attempts a "Visa Open" for each resource found using the "Visa Find Resource" tool.  If the port is available then .....I do something, if the port is not available, it is supposed to return an error.

 

OK, THAT WORKS but...

 

If there isn't anything available at that port, then it waits 5 seconds before it times out.  HOW on earth do I shorten that timeout?  All the functions that affect the timeout seem to affect the timeout after the resource is open, and the one that is attached to the visa open doesn't seem to have any affect.  This is a big problem, because it will end up waiting a minute if it can't find the resource it's looking for.

 

-Something's missing....what I really need is more cow bell   VISA!

-Regards

eximo
_______________________________________________
UofL Bioengineering M.S.
Neuronetrix

"I had rather be right than be president" -Henry Clay
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 Hi there! So what value are you writing to the VISA Open timeout parameter? Keep in mind it is in milliseconds.

 

In addition, you might try to use a VISA Set Timeout property node. If you need to learn more about property nodes, check out this link.

Ravi A.
National Instruments | Applications Engineer
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A decade later and this problem still persists. So far as I can tell, this occurs with a TCP VISA alias which is mapped in MAX, but the device is offline/disconnected. 

 

So far, I have been unable to find a way to shorten this timeout, or to identify this condition and act accordingly. It can't be avoided by wiring a small value into the VISA Open timeout, and trying to set the timeout via property node to this session also takes several seconds and then throws an error. 

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Hello,

was there any solution found to this problem ? please let me know, appreciate any help

 

I am trying to get the interface names of USB 232 devices and get Error -1073807360 occurred at VISA Open 

 

Apart from a USB serial adapter, device manager shows that I have few other (Standard Serial over Bluetooth link) on COM ports that are detected on "VISA find resource VI" but cannot open on "VISA open:, this causes it to wait until an internal timeout > 20 seconds, which cannot be ignored by either the timeout intput on visa open or the timeout property node, and there are quite a few bluetooth serial com ports it detects (im not sure what they are but even after disconnecting headphones, logitech mouse adapters etc.. they still populate in device manager, if i uninstall them they come back on their own)

 

so overall time it takes to throw this error is in minutes. Error -1073807360 occurred at VISA Open 

 

when i drop the labview VISA resource name control, the drop down shows few COM ports with icons on the left (my assumption was that these refs are not closed) so i use open sessions.vi and for loop close all, but still the icons dont go away nor the error.

 

freemason1_1-1698095769544.png

 

freemason1_2-1698096352132.png

 

if i ignore all the errors it will eventually get the names of the COM ports specifically the usb rs232 adapters which im trying to populate for the user. but i have to wait a long time to get through each error of the bluetooth serial links and there is no way to give bluetooth items to be excluded in the search for visa devices.

 

any help is appreciated

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