Use these constants in the level parameter of the InstrSession.GetHandle and the InstrSession.GetCOMDriver methods to specify what kind of instrument API instance handle or ActiveX interface to return.

Session Manager assumes that a VXI plug&play -specific driver handle is also the I/O handle, which is a valid assumption for the majority of VXI plug&play drivers. For VXI plug&play drivers for which this assumption is not true, no standard way exists to obtain the I/O handle.

• ClassDriver –(Value: 1) Specifies that only IVI sessions can return a class API handle. Use a class handle to control an instrument using an IVI class driver or an IVI class COM interface. VXI plug&play and VISA are not applicable.
• DefaultInterface –(Value: 0) Specifies that IVI returns a class API handle, VXI plug&play returns a specific API handle, and VISA returns the I/O handle.
• IODriver –(Value: 3) Specifies that IVI, VXI plug&play , and VISA sessions can return an API handle. Use an API handle to control an instrument communication library, such as VISA.
• SpecificDriver –(Value: 2) Specifies that IVI and VXI plug&play sessions can return a specific API handle. Use a specific API handle to control an instrument using an instrument-specific driver. VISA is not applicable.

See Also

InstrSession.GetCOMDriver

InstrSession.GetHandle