convert and plot unscaled data from Labview to scaled Matlab

[Richard Z]

I want plot data that was acquired with Labview in Matlab. I have looked over the Graph Aquired Data VI and the Cont Acq&Graph Voltage-To File(Binary) VI but I can't quite figure out what they are doing in the Convert Unscaled to Scaled sub-VI. I have 60 channels and the header contains three items for each which I believe are SampleClk.Rate, Offset, and AI.DevScalingCoff (or gain maybe?).

What is the equation for converting raw binary data to something with the same plot that the above Labview VIs have? I am using a PCI-6071E on a XP pc if that makes a difference.

Thanks!

[Sandra_T]

Hello Richard Z,

It looks like you want to use Matlab to plot the data that you have acquired in LabVIEW. Here are some resources that you can reference:

How LabVIEW Stores Data in Memory

Discussion Forum: How can I read labview 7.1 binary data into matlab 6.5?

Discussion Forum: How to read scaled data in Matlab?

With regards to your other question on what the convert unscaled to scaled vi is doing. Double-click on the subvi, this will open the subvi to display the front panel. Press ctrl+T, to tile the front panel and the block diagram. You will then see how the waveform is built. The value of the waveform component is a polynomial of the offset, data raised to the power y multiplied by the gain. I think the best way is if you take a look at the code for better understanding. Please let me know if this is still unclear.

Regards,
  Sandra T.

Applications Engineer | National Instruments