How to read from GPIB using Signal Express?

[Gaudier]

Im trying to plot curr vs. voltage using a Keithley 2400 SourceMeter and a GPIB as interface. I want to plot current values(y-axis) from -50V to 50V(X-axis).

Im tired of trying to do so with LabVIEW, can anyone help me?

[MichaelChaney]

Hi Gaudier,

GPIB can't be used directly with SignalExpress, but it can call VIs that were written in LabVIEW, including GPIB VIs.  Page 6-1 of the SignalExpress Getting Started Guide explains this in more detail:

http://digital.ni.com/manuals.nsf/websearch/0D916FAF08E693C486256ECB005507BA

I'm sorry to hear that you are frustrated with LabVIEW.  There are many examples available in the NI Example Finder, which can be found under Help >> Find Examples...  You can browes for GPIB, Graph and Chart examples.  We also have a free LabVIEW Introduction Course that you can download:

http://zone.ni.com/devzone/learningcenter.nsf/03f7c60f17aad210862567a90054a26c/60c2782788a811c986256...

This course presentation is designed to help explain the fundamentals of LabVIEW so that anyone can get started programming in just a few hours.  I hope this information helps to relieve any frustration.

[MichaelChaney]

Hi Gaudier,

It turns out that SignalExpress 1.1 now includes support for GPIB instruments that have an IVI-C driver available for it.

http://ni.com/signalexpress/whatis.htm

Instructions for using IV Instruments can be found here:

http://digital.ni.com/public.nsf/websearch/589469164F1FCC0F86256FFF007368AD?OpenDocument

Unfortunately, when I searched for an IVI driver for your Keithley 2400, I found that there isn't one available yet.  Here's what Keithley has to say about this:

http://www.keithley.com/support/data?asset=10321

This info is dated July 2002, but I did not find any newer info to the contrary.

[Gaudier]

Hi Michael, I'm only tired, but I haven't given up LabVIEW yet. I tried different VI's I searched for examples but I couldn't get them to work correctly. I tried "KE2400 source voltage current measure with PnP drivers" and it gives extremlly wrong values, I also tried Read VI, but if I use this one I also Have to open Block Read setup and Data select to select only current or else it will give me all parameters in the graph.How can I get these 3 VI to work as one? I went to a NI seminar were they showed Signal Express so I ask, he told me that in deed I could do a sweep using a GPIB and measure current with ease. So I downloaded the 30 days Signal Express evaluation; but it looks like it is not that easy.I tried to call VIs written in LabVIEW but it did not accept one.

Thanks for your time.

JR Gaudier

PUPR Plasma Lab.

[cymrieg]

There is an IVI driver for the Model 2400's on the keithley web site.

The Ke24xx driver is a VXIPnP style

The Ke2400 driver is an IVI driver.

There is no IVI SourceMeter class so this driver conforms to the "Other" class. There are some DMM class functions in the driver. Not sure if SignalExpress requires that the driver conform to an IVI class or not.