Timebase plot flickers using SV measurement suite

[m_tahir_m]

hello every one!

I have already sent my Timebase&orbit Plots.vi, which has nearly the same code as in the NI example "Orbit and Timebase plot (Analog Tacho, DAQmx).vi" for Sound and Vibration Measurement Suite...except i emend the configuration portion of the code to run with pci-6143 instead of DSA h/w.

problem is ---its timebase polt flickers as i already explained before.

can anyone help me regarding the same issue,  am i mistaking somewhere in my code? , if so where?

anxiously waiting for some response.

best regards

[QiaoGuo]

1- Your emended code, based on our example, is a continuous acquisition one. Because you did not tell us your task settings at first, we guessed you might provide an N-Sampling mode, which is a commonly mistake customers usually make.

2- The timebse plot DOES display the real time data. According to the control "timebase buffer size (rev)", it displays the latest set revolutions of timebase plot. You can compare its x scale maximum value with "Speed Profile" to verify whether it is real time in every iteration. The x scale of "Acquired Waveform" is absolute time mode, you can also compare with this after changing its display format of x scale.

3- Due to the filtering operations inside and the need to ouput the integer revolutions, the X scale's maximum value of timebase plot in each iteration is a little bit less than the one in "Acquired Waveform or "speed profile". However, we do buffer these data inside our VI and use them in the next iteration for continuity.

4- For filtered timebase plot, there are more filters inside for signal processing, thus the X scale's maximum value of filtered plot is less than the unfiltered one. That explains the reason of the flicker when you toggle few mouse clicks between view options of plot on the tree legend. (Once the data and the display range is updated, it will have the temporary process from compressing on the right to displaying in full range, but that does not mean incontinuous)

Please let me know whether I am clear enough for your questions.

[m_tahir_m]

great! thank you very much QiaoQuo for your detailed answes of my questions.

I talked about offline flikering of plots i.e. clicking unfiltered and filtered as i wanted to clear wether this problem of flikering is related with online flikering or not....or a bug to be fixed at NI side?

anyway,  things are more clear to me to carry on my work. but the flickering in time base plot is still to be removed while working online.

Is there any mistake in my attached code which is causing this problem and where? please note that task is continuous.

thanks again and best regards

[QiaoGuo]

There is nothing wrong with your code. The flickering problem is due to the timebase plot, regardless of online or offline.

The timebase plot was implemented by LabVIEW XControl, when the display data is updated, it should update the range together instead of first maximum then minimum.

We will invesitigate the issue and may fix it in our next release.

[m_tahir_m · Accepted solution]

thanks QiaoGuo for your help.

see you soon again and best regards