Can I reprogram Oscilloscope from NI ElVIS II

[Namit]

Hi,

I'm trying to record a waveform using the oscilloscope from NI ELVIS II then draw the graph using Java.

I am having trouble with the time base of the log file as it looks like this: 

Can i reprogram the NI ELVIS Oscilloscope so that:

1. The time[0] will start off from 0 (finish at 100)

2. I want to get rid of the title

3. The Y[0] will be number with the exact format, ie. 0.3859572736.

In short, I want the log file to be as like this: 

 I'm using Labview 2014 and NI ELVISmx 14.0

Thank you for your help.

[GerdW · Accepted solution]

Hi Namit,

draw the graph using Java.

Why don't you use LabVIEW for this task? It comes with routines to handle this specific file format…

Can i reprogram the NI ELVIS Oscilloscope so that:

1. The time[0] will start off from 0 (finish at 100)

2. I want to get rid of the title

3. The Y[0] will be number with the exact format, ie. 0.3859572736.

1. All you need to do is some simple math: time[n]-time[0] will give you the relative time between start and current time…

2. Do some simple string handling in JAVA…

3. JAVA should be able to handle numbers in scientific format the same way as any other programming language - so what is your problem?

I haven't work with NI-ELVIS so far: is this "Oszilloscope" a ready-to-use software? Or are you able to look into its block diagram? When you are you could also change the data saving routine the waqy you like…

When

[Donovan_B · Accepted solution]

Hi Namit,

As GerdW mentioned, Java should be able to handle the file as it is already saved by using some small math functions and numeric formatting.

However, if you really do need to modify the log file from the ELVISmx Oscilloscope, you can do so. When you install ELVISmx, the source code for the software instruments is included. For the location on your computer, see this link.

The Scope log is created using the Export Waveforms to Spreadsheet File (1D).vi provided by LabVIEW. The logging code is located in the top case structure of Scope.vi in the "Log" case. You can replace the existing VI with whatever log information and formatting you would like. However, there are some caveats.

First, when an instrument is launched through the NI ELVISmx Instrument Launcher or the Windows Start Menu, a LabVIEW-built exectuable is what is launched. This is the source code that has been compiled into a binary that runs in the LabVIEW Runtime Engine. In order to get your modified code launched from the Instrument Launcher, you will have to build the code into an executable and copy that executable to the proper location (Program Files (x86)\National Instrumennts\NI ELVISmx). This requires LabVIEW Professional or the LabVIEW Application Builder add-on. If you just want to modify the code and run it in LabVIEW instead of building an executable, you don't have to do any of this, but your code will not be launched through the Instrument Launcher. If you do build an executable, I would suggest making a backup of the Scope files before overwriting them.

Second, for NI ELVISmx 14.0, the executables are built using LabVIEW 2012, which means they require the LabVIEW 2012 Runtime Engine. This is installed with ELVISmx 14.0, but if you build your modified code into an executable using LabVIEW 2014, your scope will require the LabVIEW 2014 Runtime Engine.