agilent 4395a impedance analyzer

[brigitte]

Hello,

we have an impedance analyzer AG4395a with a GPIB 488.2 that we would like to control using labview. I have been looking for drivers for this instrument and found two. One of them doesn't work and it seems impossible to solve the problem without understanding basic progammation. Moreover, none of the drivers does exactly what we mean to do. It seems that the only two drivers that I can use is the initialize.vi and close.vi. My problem is that I know what we want to do (plot the parameters (R, L, C) of the fitting of the conductance as a function of time) but I have no idea of what type of drivers (if they already exist) I have to use between the initialize.vi and the close.vi. Any help will be welcome because I really feel lost!!!!

Thank you

[smercurio_fc]

I assume you are referring to the drivers on this page: http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=2056? If so, which driver did you download?.

As far as which VIs you need to use, you really need to read the manual of the instrument to learn how to use it. The drivers assume you know how to use the instrument. The drivers themselves just send the commands that do the same thing you'd be doing by pushing the instrument's front panel buttons. 

[brigitte]

Yes I have the plug and play driver from this site. But I have another one for Hp4395 that was downloaded by a colleague (but I don't where he got it from). I have been trying to use the simplest drivers, for example, the initialize, one which allows me to choose the spectrum/impedance or network and then the close.vi. First I don't understand very well how to connect the different drivers. Then, when I put these drivers on the block diagram and connect them (not using all the connections because I do not understand them), nothing appears on the front panel.

Thank you very much for your answer!

[brigitte]

Excuse me but I have another question. When I am using labview: do I have to program every step to use the network (select the type of network, the log scale, etc...) or can I do this manually and then use labview from this point for example to plot something in real time? In other words does using a labview program necessary mean just put the network on and then doing every step using the computer?

[jack47]

I your are asking if you can set-up the analizer manually and use LabVIEW to read the data, then yes it should be possible.  For the question about the connections, feel free to post what you have for a VI so far and it might be easier for the community to help.

[brigitte]

The example I was talking about is connecting the three following drivers:

initialize.vi

mode.vi

close.vi

Some of these drivers have more connection than the others, how do I connect them?

The initialize.vi asks for connections on its left but I do not know what to connect.

I am trying to send the driver hp4395 with everything. Can you confirm that I do not have every driver I need to do what I want: plot in real time the parameters from the fitting of the conductance. So how can I do this without understanding basic programmation?

[smercurio_fc]

That is the driver that uses the DLL provided by Agilent. I am assuming you have this, otherwise that driver won't work since the individual VIs will all have broken run arrows.

The other driver is the "plug and play" version. It already comes with a top-level VI that is user-friendly, but the code is terrible. Is this the other driver you said you tried and "didn't work". If so, what exactly "didn't work"?

In the driver with the DLL there is no "mode" VI, so I don't know which VI you're referring to.  As far as having what you need, the driver has many functions in there to configure the instrument and read from it, so from that perspective you have what you need. You cannot do this without understanding basic LabVIEW programming because you will need to wire up the individual functions in a sequence and wire the output to a graph. You will also invariably want to save the data to a file. People always want this, so it's inevitable. 

That said, it appears based on what you're saying that you have a more fundamental problem, and that is not knowing how to use LabVIEW. Have you gone through the tutorials? You really need to start there before trying to get into instrument programming. To learn more about LabVIEW it is recommended that you go through the tutorial(s) and look over the material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.

[Dennis_Knutson]

Well, that's not a plug and play driver. And, there is no VI called Mode in there.

In general, you would connect the Instrument Handle Out of one VI to the Instrument Handle In of the next VI you want to call. Do the same thing with error out of VI one to error in of VI 2. This is just basic LabVIEW dataflow and you really need a basic understanding of that and LabVIEW in general before you do anything.

Of course some VI have more inputs and outputs than others. It's like parameters in a function call in text based programming languages. For example, the Initialize function has inputs called ID Query and Reset Device. If you want the function to query the instrument for it's ID information, you would wire a Boolean true to this input. If you don't want the instrument to reset, you would wire a boolean false to that input. What you wire and what values you pass will depend on how you want to program the device. In LabVIEW, you should have context help turned on and as you move your mouse over a control/indicator, the help window will discribe what the control/indicator is.

You really do have to understand the instrument, the programming of it, and LabVIEW itself. There are no shortcuts .

[billko]

---

Dennis Knutson wrote:

Well, that's not a plug and play driver. And, there is no VI called Mode in there.

In general, you would connect the Instrument Handle Out of one VI to the Instrument Handle In of the next VI you want to call. Do the same thing with error out of VI one to error in of VI 2. This is just basic LabVIEW dataflow and you really need a basic understanding of that and LabVIEW in general before you do anything.

Of course some VI have more inputs and outputs than others. It's like parameters in a function call in text based programming languages. For example, the Initialize function has inputs called ID Query and Reset Device. If you want the function to query the instrument for it's ID information, you would wire a Boolean true to this input. If you don't want the instrument to reset, you would wire a boolean false to that input. What you wire and what values you pass will depend on how you want to program the device. In LabVIEW, you should have context help turned on and as you move your mouse over a control/indicator, the help window will discribe what the control/indicator is.

You really do have to understand the instrument, the programming of it, and LabVIEW itself. There are no shortcuts .

---

It's kind of a weird situation because once you understand the instrument, the programming of it and LabVIEW itself, you don't really need the drivers, because by then you can write your own custom ones.  😄

Bill

[brigitte]

You are right I have to understand more about labview but I have been reading about it during the last weeks and I find it very confusing. I did the first three exercises of getting started guide but I couldn't do the 4th chapter which is about communicating with instruments (DAQ). The first exercises where good to understand things like bock diagram and front panel, however the drivers are quite more difficult to understand. The vocabulary used in the tutorials is too specific and it is asssumed that you know abbreviatures which turn this tutorials very complicated. As far as the network analyzer is concerned, I have the manual impressed and I know how to do what I want using the manual. My problem is that I cannot save the data manually in a graph. 

I am sorry, you are right there is no "mode.vi" what I meant was the vi that allows to choose the mode impedance, network or spectrum.

I did not use the plug and play driver because I did not find the initialize.vi and close.vi and from what I read I thought it was necessary to have these to drivers to program my instrument. Moreover this plug and play drivers have no comment to understand what it one does and block diagrams are to complicated to be decripted.