select gpib enet 100 in labview

[Donkey Rubarb]

I am using Labview to get measurement results out of oscilloscopes,logic analysers etc..
Nowadays I use a GPIB-ENET/100 as gateway, programming Labview for the GPIB-ENET/100 is pretty easy compared to the Agilent E2050.
I noticed that I didn't have to use the Old visa open vi. (which really stinks) to talk to an instrument.
Instead I just write my commands using the GPIB write.vi and thats it. So I don't specify anything about the GPIB-ENET 100 in the beginning or ending of my program just immediately the machine GPIB commands.
I never had any trouble working this way, until now.
I just bought a new GPIB-ENET/100 and I was hoping that my programs should also work on the new (correct installed) GPIB-ENET/100.But they didn't.
Though in
Max I can control the instruments with both interfaces, it seems that every time I run my programs in Labview the old GPIB-ENET/100 is adressed, strange cause it is nowhere specified.
Is it necessary to specify in the beginning which GPIB-ENET /100 I want to use or can Labview just look at the GPIB adress and than see which gateway has the instrument with the corresponding adress attached to it and than send all his messages to this gateway.

[DiegoF]

Hi,

LabVIEW determines which interface to use using the address string. The most general form of the address string is ID:PAD+SAD, ID is the interface number, PAD is the primary address and SAD is the secondary address.

If you just write a number, the VI will assume no secondary address and interface 0 (GPIB0).

Notice in MAX that each installed interface has a number assign to it. This is no the interface's address, it is the ID used in the system to differentiate the different interfaces that may be installed.

When you have one interface it defaults to 0, which is why your VI is working. Adding a second interface, it will be most likely GPIB1.

When using the GPIB VI, you have to make explicit to which interface you are refering to, if not GPI
B0 is assumed. Use "1:PAD" to use the other ENET.

There is no need to use IP address. the driver will know whihc interface you want to use based on the ID number.

Hope this helps.

DiegoF
National Instruments.

[LesHammer]

> Nowadays I use a GPIB-ENET/100 as gateway, programming Labview
> for the GPIB-ENET/100 is pretty easy compared to the Agilent E2050.

If you use Agilent VISA then the Agilent E2050 is very easy to use.
Simply put the IP address in the IO Configure form, then use it as you
would use any GPIB card.
(I did the E2050B firmware upgrade, so I speak from experience.)

Les.Hammer@CompleteTest.com

[Donkey Rubarb]

Hi Diego,
I understand the problem but not the solution...
If I am wright I should add 1: infront of the primary adress of the instrument to use the GPIB-ENET 100 with interface number 1, but this didn't seem to work?
When Labview enters the first GPIB write.vi with the adress string 1:7(Gpib adress of the equipment) attached to it, Labview stays for iternity in this vi?
So he doesn't seem to find the specified inteface or the command is completely wrong.
What am I doing wrong?
Tx

[DiegoF]

Hi Tx,

If the interface is not reachable, the driver should timeout after aprox 10 seconds with a low level error (EDVR).

Can you detect the device using MAX, Scan for Instruments?. Right click on the instrument and select Communicate With Instruments. Can you query the instrument's ID?.

Use a simple VI that queries the ID of the instrument.

Also, check the examples included with LabVIEW. The example actually use VISA. You may want to check it out and see if VISA is easier to work with.

DiegoF
National instruments.