Unable to use the GPIB-ENET/100 with LabView

[fpaulin]

Hi,

While using the GPIB-ENET/100 to control a Keithley DMM 196, I seem unable to use LabView itself to do it.

The MAX software can control the instrument properly ( hardwares are fonctionnals ).

The ENET / 100 Drivers that I found for LabView at http://zone.ni.com/devzone/cda/epd/p/id/4563 are not working, or more specificaly:

The instrument is flatly ignoring ANY command send through the ENET_Write.vi despite the fact that the VI is not calling any error.

But the ENET_Read.vi seems to be working fine.

My feeling is that the problem is due to the fact that the 196 is old and may not follow the current standard for GPIB communication.

The ENET_Write.vi command formating that build the ASCII string for the GP-IB is probably the probleme here:

REN must be sent for the instrument to work on remote, the termination character is X for eXecute (not LF-CR!!) ( Command RENX )

F0 set the instrument to Volts DC ( command F0X )

F3 set the instrument to Current DC ( command F3X )

So RENXG0F3T5X Would tell the instrument : RemoTe ON *eXecute* Header ON + Curent DC + Single Shot Trigget on X *eXecute*

Afterward every instance of X with no other command tell the instrument to take a reading and send it to the GPIB bus with a descriptive header (Ex: NDCI+000.0024E-6 )

The intrument is beheaving as if the RENX command was never recieved. In fact, the instrument fails to receive any command from the Write vi. 

The ENET_Write.vi is password protected and I could not to find documentation on how to use the GPIB-ENET/100 without those drivers in LabView.

 can you help me with this?

Thank you.

[Scott-M]

Hi fpaulin

The drivers you linked are specifically for using PDAs with GPIB, if you're working on a normal PC I would start by installing the full driver NI488.2 (you can see in the readme that is supports the GPIB-ENET/100)

NI-488.2 Download

You mentioned that you were able to control your instrument through MAX but were having issues using LabVIEW, by using our NI-Spy software you could get a spy capture of what commands MAX is sending vs what commands LabVIEW is sending, this might help us zero in on what's going wrong.

Performing a Good NI Spy Capture for Debugging/Troubleshooting

Finally you might want to try using one of our pre made instrument drivers, we have a driver for your instrument available on our instrument driver network.

Keithley ke196 Meter

Let us know if you run into any issues.

Thanks

Scott M.

[fpaulin]

Thank you for the prompt answer.

I looked into the 488 driver, I was using the 2.2.7.0 supplied with the Enet/100.

Here is the NI-Spy file:

Lines 1 to 16, I am using MAX in manual mode.

Line  17 the command was send with MAX after I attempted to use "X" through the ENET_Write.vi. ENET_Write.vi went into ERROR 6. There is no record of this command.

Line 18 to 25 I was attempting to reset the Keithley.

Line 25 to 34 I used the other Keithley to see if the GPIB bus was still alive.

Line 35 to 54 I restarted the "communicate with instrument". The communication is totally blind, the instrument is ignoring me.

Line 55 to 86 I just restarted MAX and it was working again. From MAX.

Unfortunately, the Kei196 driver is for GPIB, not the GPIB-ENET/100 device. ( https://www.ni.com/en-us/support/model.gpib-enet-100.html )

The fact that MAX is working leads me to believe that the hardware is working properly.

Thank you for your help.

[Scott-M]

Hi fpailin,

I am still looking at your spy capture trying to figure out what might be going on, however I though I would let you know right away that the GPIB driver for your instrument, linked above, should be blind to how it is connected to your computer, as long as a GPIB bus is being used to connect to your instrument. The driver should work for PCI-GPIB, USB-GPIB, or GPIB-ENET/100, if you wanted to give it a try.

Thanks

Scott M.

Message Edited by Scott-M on 02-16-2010 05:02 PM

[fpaulin]

Hi,

You are correct: "GPIB Write" and "GPIB Read" from the native GPIB tools work perfectly with the ENET/100. I am now pooling 2 Keithley 196 in 160 ms and the communication seems stable.

Thank you for your help.