How to Mix Class (green) and Specific (blue) IVI Driver Calls in LabVIEW

Question

I am trying to mix class and specific driver calls within LabVIEW. Is this possible or will I likely encounter errors?

I have already downloaded the IVI specific driver from the following link:

Agilent Technologies hp34401a Meter - IVI Specific Driver

And I received the IVI class drivers when I installed the IVI Compliance Package.

IVI Compliance Package 4.6.1

I am coding in LabVIEW and am just curious if I can mix the class VIs (green) with the specific VIs (blue). Does anyone have any experience with this?

Answer 1

Watch the following Video on Youtube. You may absolutely mix calls. However, be aware that mixing driver calls will limit the ability to interchange instruments. This feature is normally possible when coding with class driver calls only. If you do not need to use class driver calls, then you may want to consider using the LabVIEW plug and play (project style) version of the driver from www.ni.com/idnet.

Up and Down Casting in LabVIEW (Mixing Specific and Class Driver Calls) http://www.youtube.com/watch?v=bPr78g7q7d4

Answer 2

Mixing two different APIs that target the same hardware is a bad idea at first sight. Choose the one that suits your needs, and stick with it. Or, if you know exactly what you're doing, and that the API mix is documented, feel free.

Answer 3

IVI (Interchangeable Virtual Instrument) can be a good choice when you need to work with more than one instrument provider for a single function (DMM, scope, counter etc...) Reasons might include equipment cost, availability or a even requirement of the design (gov't. contract).

http://www.ivifoundation.org/about/Overview.aspx

Since I only use LabVIEW, I tend to choose native "plug and play" instrument drivers when they are available. With native drivers, you can debug at a lower level than IVI.

Most IVI drivers I've worked with are written to the minimum spec. They work, but if you need to access any vendor specific features, you often need to write that yourself and end up resorting to the plug-and-play version.

A plug-and-play version of the driver for your instrument is available on the NI Instrument Driver Network (IDN).

http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=014E7F05D12C6F8BE0440003BA7CCD71