I'd like to suggest that you submit a request for an instrument driver from NI's instrument driver network, but it looks like Agilent has dicontinued this product, so I'd know how many resourses they could allocate to deveoping a driver for it...
So unless someone out there has had some experience communicating with the instrument, or has a driver for it, we should first first make sure that you can communicate successfully with the instrument. If your instrument if SCPI compliant, then it should respond to certain commands, such as *IDN? and MEAS:DC?. Have you verified that it can respond to those commands? The easiest way that I can think of to do this is to go to MAX and test it out there. Have you already set up MAX to find your instrument? If you have then you should be able to right click on the instrument, and choose "Communicate with Instrument", or something to that effect. This little utility should allow you to type in *IDN? or MEAS:DC? or other commands, and perform queries. If you have any questions about these suggestions, or if you have already tried with no success, please repost.
Also, what NI-488.2 driver version are you using? What ADE: LabVIEW? CVI? VB?
