I have a lab with 10 systems, using an Agilent E3631A Power Supply. The Software is in CVI. The comm is GPIB via the GPIB-USB-HS. On the systems that use 488.2 version 2.8.1, all works well. On the newer systems that have 3.0.2 installed, 2 errors are generated when the software reads the current from the instrument. The instrument beeps twice, and there is an error 550 and -420 in the buffer (Command not allowed in local mode, and unterminated errors.)
Needless to say, the instrument is not in local mode when the commands are sent, and the commands are terminated correctly. Again, in 488.2 version 2.8.1, the errors do not occur.
Max setups between errant systems and non-errant systems are identical, except again, for the 488.2 version number.
There is a LabVIEW driver available for this instrument from the ni site. Downloaded it, ran the "INIT" function, and then [without closing anything] ran the test software in CVI. No errors. I reversed engineered the LabVIEW VI into CVI [as best as possible]. No joy, error persists.
So my questions are on several levels, since we use both CVI and LabVIEW. Why did the reverse-engineered VI not eliminate the problem in CVI? Is there so much more going on 'under the hood' in the LabVIEW GPIB session that duplicate commands and setup prefs have different results between the two platforms? Also, is there any existent knowledge about 3.0.2 vs 2.8.1 and this kind of behavior? I can revert to 2.8.1, or if I wanted to get tricky I'd try building the LabVIEW VI as a dll and try calling the init routine that way...
