User`s guide

Using .NET with VEE 7
VEE User’s Guide 311
.NET and IVI Drivers
What is IVI? IVI is a new instrument driver standard being
developed by the IVI Foundation. The IVI Foundation is a
consortium established to promote specifications for
programming test instruments. These specifications provide
multiple benefits but primarily make instrument
interchangeability simpler. For a review of the IVI
Foundation, go to http://www.ivifoundation.org/.
Why would you want to use an IVI- COM driver? Assume two
hardware vendors provide an IVI- COM driver for each of
their DMM’s. To meet the IVI standard, the base drivers
must be interchangeable. This means that if you start with
one vendor’s DMM and matching driver, you can switch to
the other vendor’s DMM and driver with no other changes to
your program. Your code is reusable without any
intervention.
Install the IVI- COM drivers when necessary. To find drivers
for your instruments, go to http://www.agilent.com/find/adn.
If you are an ADN member, select Downloads from the menu
⇒ Drivers by Driver Type ⇒ IVI-COM Drivers and Components. If you
are not an ADN member, it is an online source for Agilent
drivers, evaluation software, documentation, and white
papers. To sign up for this free service, fill out the online
registration form for new users.
Once the IVI- COM drivers are registered on your system,
they are available just like any other COM component and,
like most COM components, will appear on the COM tab of
the Device ⇒ .NET Assembly References in VEE.
How do VEE and .NET make IVI- COM drivers available? Via
.NET’s COM interop, the IVI- COM drivers become available
to VEE. If there isn’t a primary interop assembly available
for a COM DLL that you select, VEE attempts to generate an
interop assembly (or more than one if the COM .dll
references other type libraries). After the interop assembly is
referenced, the IVI- COM driver can be invoked just like any
.NET object.