Old visa open error

[Donkey Rubarb]

I have written a program for the TDS 680 oscilloscope, it works on some lan interfaces we have but not all.
When it doesn't work there is problem "Old visa open".
I tried to use visa open instead (I use lv 6.01)but without succes. Still I can communicate with the instruments through MAX. This is not the only program which has this problem and I have no Idea what the problem could be. The interfaces we have are HP E2050A
(these are old ones but on SOME of these it works)the other interfaces are GPIB/ENET100 and here it doesn't work for the TDS program, for other programs it is the other way around.
Yep shure can use some support!!

[Randy_H]

My first suggestion is to update your LabVIEW to 6.0.2. LabVIEW 6.0.1 has a lot of errors in it that were introduced by mistake. That is why LabVIEW 6.0.2 was released. Next, make sure that you have the latest version of VISA from our web site. This can be found here.

I am a little confused by some of your information. You say that your TDS 680 is an ethernet instrument? If so, then the GPIB/ENET100 is a GPIB controller. It allows one to run GPIB commands to an instruments over your netwo
rk by converting the GPIB string to a network packet and sending it to the ENET100. The ENET100 then chages the network packet back into the GPIB string and sends it out on its GPIB bus.

Randy Hoskin
Applications Engineer
National Instruments

[Donkey Rubarb]

yes indeed the TDS 680 is connected on a network through the GPIB/ENET100. Lan interface is maybe a wrong name for it, gateway might be better.

Ok I will check for a Update.
But don't you think that it might have something to do with maybe some of the interfaces cause like I said the same type of gateway (the E2050A or GPIB/ENET) sometimes works and sometimes not.
And when for instance gateway A works and gateway B doesn't this will always be the case for a certain program.
The place where they are, offcourse doesn't mather (I checked it just to be shure).
Can it have something to do with an application that ran before on an Gateway?

[AaronK]

Hi,

It seems very strange that your problems are intermittent. There must be some attribute that causes this to happen. I would recommend focusing on one of the two box's and work through all the variables to try to determine what could be the cause of the problem. Consider using NI-SPY to track it down to a call or series of calls that seem to be creating the error and then compare that to another section that works properly.

I hope this helps out!

Best Regards,
Aaron K.
Application Engineer
National Instruments