resource name

[John123]

Hi,

I am working on a VB .NET/C# app to talk to NI PXI 2503 switch card. Is there any way I can query the card to get the resource name/topology before initializing the card? Thanks.

[NatasaLingurovska]

Hi John123,

You can access the recourse names and limited card info using the niModInst calls, but you will not be able to access the topology of the card before initialization. The function to scan the computer to give the resource descriptors of all boards specific to a Modular Instruments driver is called niModInst. The niModInst Open Installed Devices Session call will create a handle to a list of installed devices supported by the specified driver. Call this API and select the name of a National Instruments instrument driver, such as NI-SWITCH, from the driver control. This call searches the system and constructs a list of all the installed devices that are supported by that driver, and returns both a handle and the number of devices found. The handle is used with other functions to query for attributes such as device name and model, and to safely discard the list when finished.

This is a link to the help files for available niModInst function calls.

'Hope this helps.

 

[John123]

Thank you for the reply.

I built a dll using LabVIEW - VISA Find Resource, VISA Open, Property Node, and VISA Close. Now I can get installed PXI cards and information like manufacturer id, name and model name. Can I get topology information in this dll or I need additional VIs to get topology information? Please advise. Thanks.

[NatasaLingurovska]

What topology information exactly do you need? When you initialize a session, you specify what topology you want to use, thus you can't get the topology information without first starting a session. The issue is not whether you should include this vis in your current dll. The problem is that there is no info to be accessed before a session is started.

I hope this helps. Please let me know if you have any additional questions or concerns.