I was wondering if anyone could help a rookie LabVIEW user. I have a Hantek 6074 scope that has a Labview VI example. This scope works fine in both the OEM software along with a really nice VI I found on You Tube ( https://www.youtube.com/watch?v=42CiDx98zlE ). When I use the provided example my voltage is way off. In the attache picture the VI staggers channel 1 through 4. Channel 0 has a zero level of 190. I can adsdjust the 0 levels tp start at 0 on the Y axis. That is not my problem. The issue is , the scalling is off. a 2 volt sqaure wave has a measument of 190 (low) to 255 (high) I assume the 0 to 255 scale has to do with the scope being an 8 bit scope? I am able to lower the voltage reading by increasing the Pchvolt array to 11. It seems 1 to 11 is the range. I can here the relays change state when I enter certain numbers. I there somthing I am missing. Sorry for the amature nomenclature. I would also love some input on any Labview training sources if anyone has a reccomendation. I will attach the VI file and drivers. Thanks JKesse

@Jesse47 wrote: As far as handleing attenuators I am pretty expeienced with scopes and the use of attenuators. I am not sure if you are asking if the manual has any info on programatically using them in Labview or the oem software . I know how to use them with the OEM software along with the scaling property in labview. The voltage I measured in the picture is a 2 volt square wave and maxes out to 255 . Any labview scaling vi that I add does not apply in a linier fasion. I am way to inexperienced to make a new VI . I have worked on integrating scopes into LabVIEW for years and one of the big issues that comes up is the quality of labview drivers and example code provided by the manufacturer. In some cases all you need to do is download a manufacture driver package and you are off an running wit every feature and function you could imagine and in other cases you have to write everting from scratch because what is provided is garbage or does not exits. I have never used a hantek scope but it sounds like their provided code is not the best and is not going to work for your application. In this case someone is going to need to write the code that works for it. The 8bit data stream is typical for a scope. As it turns out it worked great with GPIB since that was an 8bit parallel data bus so that was they way scopes worked for years. You would get a scaling factor and then all the data would be 8 bits unsigned integers. Wen you say that that a scaling factor does not apply linearly, what are you expecting? If you are measuring a 2v square wave and you are getting back 255, your scope is probably in the +/- 2v range so you will have some 8bit quantized stepping if you zoom in on the 2v region, this is normal in the scop and in labivew. If you are going for enhanced resolution or some kind of interpolation that will be out of reach if you can not make a new vi or write the driver code that requests floats from the scope.

LabVIEW

Scope VI

Solved!

@Jesse47 wrote:

Thank you for your response. Very impressed with your knowledge in this area. I was watching a video on someone who designed a pretty nice VI break down the process. He did mention interpolation. Can you suggest a starting point for someone interested in learning LabVIEW and wants to focus on Data acquisition? I am an Industrial power generation tech so my programming knowledge is non existent. I have made some basic Vi's to automate load banks and to preform some diagnostic testing using the USB 6009 daq. I really enjoy making a custom programs and would love to be able to do more complicated tasks in labView. Again , I appreciate your previous answer.

Try starting here: https://www.youtube.com/watch?v=GKhai8DDoss

and here: https://www.youtube.com/watch?v=HkybKgnF0sQ

and here: https://realpython.com/

: )

At this point in time I am no longer recommending LabVIEW for any data acquisition, machine control, or data analysis software development. If you are new to programming, learn Python! You will get much more milage out of Python and Python is much easier to learn. The only reason you should learn LabVIEW is if you are working for (or want to work for) a company that is already using LabVIEW in their systems. That way the company can pay for your (expensive) seat of LabVIEW and all the expensive ( but very nice) LabVIEW training modules. Did I mention learning Python is free? and just in case it is not obvious by now I would like to say Python a few more times in the spirit of Monty Python, PYTHON Python python py p ....

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Have a pleasant day and be sure to learn Python for success and prosperity.