Property to allow duplicate visa sessions on one port?

[jsab500]

Hi,

I need to be able to open at least 2 sessions simultaneously to the same VISA resource. I have so far been using the labview drivers that came with the device (third party drivers), and these have been fine (I couldn't get the source code). The connect to device function, which I've attached, seems to create a VISA session to the device. If I leave the VI that opened this session running and use a different one to connect to a different card on the device, this overwrites the session in the original VI. I've realised that if I was creating the VISA sessions myself I could use VISA Open and make "Duplicate VISA sessions" true, but I'm not obviously. Is there any way to make it allow duplicate sessions after the session has been opened? I searched the available properties but couldn't find anything that looked reasonable.

 I've also attached a screenshot of a probe of the VISA resource name.

Thanks very much for your help,

James

[Richard2950]

As a work-around you could use a single session and use semaphores to make sure that only one vi is using the session at a time.

[jsab500]

Thanks for the idea, but I need to have multiple sessions. I know it will work with the hardware, as the software that came with the device can keep 4 separate sessions open.

So is it impossible without opening the VISA session manually? Anyone?

Thanks very much,

James