Owning Palette: VISA Advanced VIs and Functions
Requires: Base Development System
Opens a session to the device specified by VISA resource name and returns a session identifier that can be used to call any other operations of that device.
|VISA Open timeout specifies the maximum time period, in milliseconds, that VISA Open waits before returning an error. It does not set the I/O timeout. To specify the timeout used for future operations on the VISA session, use VISA Set Timeout.|
|VISA resource name specifies the resource to be opened. The VISA resource name control also specifies the session and class.|
|If duplicate session is TRUE and there is currently a session opened to the resource, another session is opened to the resource. If duplicate session is set to FALSE and a session is opened to the resource, the open session is used. A VISA session is a unique logical identifier used by VISA to communicate with a resource. The VISA session is maintained by the VISA resource name control and is not seen by the user.|
|access mode specifies how to access the device. This input accepts the following values.
|error in describes error conditions that occur before this node runs. This input provides standard error in functionality.|
|VISA resource name out is the resource to which a VISA session is opened and its class. The class matches that of the VISA resource name input. Refer to VISA resource name control for more information.|
|error out contains error information. This output provides standard error out functionality.|
If you open a significant number of VISA sessions without closing them, you decrease the available memory resources. Close the session with the VISA Close function.
|Note This function recognizes all resource strings returned by VISA Find Resource. However, VISA Find Resource does not necessarily return all strings that you pass to this function.|
Refer to the GPIB with VISA functions VI in the labview\examples\Instrument IO\GPIB directory for an example of using the VISA Open function.