LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Waveform chart in scope mode refreshes in the middle of the x-range (time)

Hi All,

 

I am playing back a previously acquired signal via a TDMS file. I am using a waveform chart in scope mode to monitor the data.

 

I have attached my VI and a sample TDMS file for it to read. Don't worry, I have scanned these files for viruses before I uploaded them - they're clean. 

 

I am wondering why the waveform chart refreshes in the middle of the x-range, and not when it reaches the upper limit of the x-range. Ideally, I would like to see the data start writing at the lower limit of the chart and fill until the upper limit of the chart, refresh and then start writing at the lower limit again.This is not what it is currently doing - it starts writing at the lower limit of the x-range, fills the chart BEYOND the upper limit of the x-range, refreshes and starts writing in the middle of the x-range. This behavior happens regardless of the chart mode and chart history. I think it has to do with the property node that I use. I should explain that the reason I'm using the property node is to ensure that I display only one cycle at a time (hence the range is based directly on the frequency).

 

Any insite would be greatly appreciated!

 

P.S. Because NI does allow users to upload TDMS files, I changed the extension to .txt - in order to open the file with my VI, just change the extension back to .tdms after you download it.

 

Thank You!

Download All
0 Kudos
Message 1 of 2
(1,723 Views)

Hi there, I looked at you code and I noticed something interesting. The chart re-graph the section that jumps if you clear the chart. I would workaround this by avoiding waveforms. Use the Get Waveform components VI to extract and plot the "Y". This worked for me.

Alejandro C. | National Instruments
0 Kudos
Message 2 of 2
(1,698 Views)