Sampling on HP 4156

[dilge]

Hello, it's me again with my very old and troubled semiconductor analyzer. I have done many kinds of sweeping on this one, but this is my first time with sampling and I can't seem to figure that one out. Does anybody have a VI where you can supply constant voltages to three SMUs and measure VMUs and SMUs at the sampling rate? I have a very old VI with a very old driver

where you can obviously not choose an SMU or supply any source but can only read. 😞

[cstorey]

Edit -  The Hp4156C has its own driver - http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=5D13BA2F1F47284FE0440003BA7CCD...

That's where your example comes from.  Its actually a pretty poor example, I'm surprised its in the driver package like that.   If you look at the 3rd sub-VI, "Configure Sampling Method.vi" there are lots of terminals that are unwired.  You can specify either a total sampling time or a specific number of points.  Once you do that then the instrument should do the rest and the example should be more useful.  You should also set the instrument timeout to match your measurement time (+ a few seconds for setup time + time to format the data + lots of time to send it over GPIB!).

I was going to provide example code, but I have a hp4155A and Agilent 4156B, so I use the driver here - http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=015E42A1245448B2E0440003BA7CCD...

The SCPI commands look similar for both, but there are probably subtle differences that are the result of new features in the Agilent 4156C. 

Hope that helps.

Craig

[dilge]

I also have that driver that you're using, it would be very nice if you provided me that code. I will at least try that, I tried working with two other drivers as well and somehow sampling is way harder than sweeping 😞

Thank you very much!

[dilge]

Hey again,

This is providing the source voltages and also measuring through the SMUs perfectly. But I also need to use the VMUs and their measurements always are NaN, when I do sweeping I can see values like  0.002 but with sampling its always NaN. Do you think somethings wrong with the following?

[cstorey]

Did you get this working?  Sorry, I've been on vacation. 

If you have the 4156C, use that driver rather than the 415X driver.  But if you attach code I can test on a 4155. 

I'll supply an example of sampling code I use later today.

[dilge]

It's alright, I now have a code that works perfectly! 🙂 Thank you for all the support.

[Amar_GradStud]

Hi Everyone,

I am trying to do the sampling measurement, but whatever I do it gets stuck at wait for acquisition complete. I dont think there should be an error there. But I cannot figure out what it is. Any help would be appreciated.  

[cstorey]

There must be errors displayed on the instrument as you are configuring the SMUs.  Use highlight execution to slow down the code an watch what happens on the instrument as the commands are received.  Watch the error codes that appear on the instrument (usually a string of numbers like 00 40 80 00 04 00) write them down and investigate.  Also put an error read in your code before you initiate a measurement and see what comes back.  I'll bet a variable name or parameter is not properly defined or something is out of range and thus the instrument can't execute the measurement. 

I believe you probably want to display and read the @TIME variable and set up the plot with @TIME on the X-axis.

Craig

[Amar_GradStud]

Thanks for your response. I have to keep increasing the wait for acquisition time to 50000s to get only 6 samples. If I want more than 100 samples, I feel I have to increase the time to more than 1M secs? otherwise there will be an error.