Hi Richard,
technically, since your'e using c#, you're not limited to the communication methods provided for by either package. The Agilent website has software examples on the 33220A available here :
http://we.home.agilent.com/cgi-bin/bvpub/agilent/expandedresults/cp_ExpandedResults.jsp?NAV_ID=-11267.536883183.03&LANGUAGE_CODE=eng&contentType=Editorial&entityType=ED39&COUNTRY_CODE=US
but nothing on c#.
The driver listed on the NI website is just for LabVIEW, however the calls used are simply GPIB calls (in the LabVIEW driver we use VISA to communicate, but essentially this can be thought of as a layer over other low level drivers such as GPIB and serial etc.)
The Measurement Studio package gives you things (at the entry level) for controls / indicators for graphs etc, plus advanced analysis libraries. Essentially it's a bolt on to the programming language of your choice inside Visual Studio, and not a replacment to it, so if you're comfortable in talking to a DLL from c#, then you can use the appropriate low level driver for the gpib interface (NI or Agilent) and do you ibwrt and ibrd style calls to send and receive info from the device. All you really need then is the programmers manual which gives you the command set it's expecting.
The LAN interface I assume you're refering to would be the ethernet/GPIB boxes? Are you looking at the Agilent ones or the NI ones?
Measurement Studio allows you to build their complete T&M solutions within one environment, because it offers not only the best tools for performing instrument communication via GPIB, Serial, and with networked instruments across the network, but it also provides advanced DAQ, motion, vision, advanced analysis and visualization tools.
Hope that helps
Thanks
Sacha Emery
Applications Engineer
National Instruments (UK)
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