Session Manager Problem

[DavidBu]

NI Support,

This is a problem that Aaron Anderberg (my associate at Tektronix) was working on for me, but other priorities have kept him away from it. I don't know who he talked to on the phone.

I have two different instruments (i.e. TDS3054B oscilloscope, Tek-Japan TG700 TV Generator), each does SCPII commands over their respective TCP/IP Ethernet connections. The first INSTR approach works fine, it is the second SOCKET approach exhibits the Session Manager problem:

* "TCPIP::192.168.1.1::inst0::INSTR" -- This type of connection does not work when I connect it to the VISA Write VI unless I set it up properly in MAX. In MAX I use the "VXI-11 LAN Instrument" choice in the Wizard. In LabVIEW, no problem getting a session from the InstrSes
sionMgr.

* "TCPIP::192.168.1.1::5000::SOCKET" -- This type of connection works fine when I connect it to the VISA Write VI, before having to do anything with MAX. In MAX I use the "Raw Socket" choice in the Wizard. The InstrSessionMgr errors instead of returning a GetInstrSession, even if I get set up in MAX.

Both the INSTR and SOCKET approach test fine from MAX. The problem is that the GetInstrSession works for the first case but not the second case.

I also found that in MAX, it was much more difficult to get the second case to show up in the Alias list. In fact I couldn't get it to list and then came back the next day and there it was listed. After it showed up in the alias list I still could not get the GetInstrSession back from the Active-X GetInstrSession method. So I am wondering if perhaps the problem has more to do with MAX/VISA than with the GetInstrSession method.

I'm not nearly as experienced with LabVIEW as Aaron Anderberg and have little experience with Lab
VIEW's Active-X, so dumb down your help accordingly 8-)

Thanks,
Dave
503-627-2922

[JoshuaP]

Hey Dave,

The first thing I would suggest is upgrading to NI-VISA 3.1 to make sure your not running into any old VISA issues.

http://digital.ni.com/softlib.nsf/websearch/8E7D54CA3A1FDECF86256E4D007ED2E0?opendocument&node=132060_US

In addition, here are some helpful links about setting this system up.
http://digital.ni.com/public.nsf/websearch/80C28CC795611E4A86256AB100209521?OpenDocument
http://digital.ni.com/public.nsf/websearch/D7D8E3E1B682022286256D4A00771A52?OpenDocument
http://digital.ni.com/public.nsf/websearch/22F1F2ABC640D5BA86256CD1003BA06D?OpenDocument
http://digital.ni.com/public.nsf/websearch/3DD043326CF5BF6786256C10005151DC?OpenDocument

I'm not sure that GetInstrSession will return for a raw socket. The raw socket connections don't cont
ain as much information as the instrument connections.

The two methods that you have listed act differently. The first method you mention will only work on instruments that are VXI-11 compliant and the second method is designed for the instruments that don't support the TCP/IP instrument protocol.

Sense both of your instruments seem to use VXI-11 I would recommend using the first method that you've listed.

I hope this helps out.

JoshuaP
National Instruments