prob with absolute time

[TaKiMi]

Hii everyone....

I have some questions to ask to u guys...firstly, I'm using serial comm to interface data into labview...There is no prob for configuration...but I have 2 mistakes here.1stly, refer to my table.PNG...I build the table using build table express...so..I enabled the date time.When I run the prog...the date/time didn't fuction anymore...It seems like its stuck with the first read...so...i have tried to open the front panel of the build table express to modify n try to put time stamp..but I think that there is no need to replace it because it had Gate waveform time array.vi already...I tried the other basic simulation to confirm it...but the date from table will run also after I start to run the other prog.

And the other mistake about write to measurement file..the situation was same as above that I tried to show the elapsed time or fractional seconds in the text file at the left side...but it did not happened.that means the fractional seconds always shown as 0.0000 till the target time...

And my last question it...How can I put a gauge and link with the waveform?because here I can't link this gauge icon with the waveform...and lastly,How could I change universal time format of x-axis from the waveform to current time...thank u very much...

[Dennis_Knutson]

You have no time data to record or to display in the table. All that you are doing is converting a couple of 1D arrays to dynamic data types and that conversion does not automatically add a timestamp. There is no place in your program that gets the current time. If you were to use the Build Waveform function, you would wire in the Y array and could wire a timestamp to the t0 input. The Build Waveform also has a dt input. You could take the reciprocal of this and use that for the dt.

You can't wire a gauge to your waveform because the gauge only accepts a scalar input. Your waveform is an array. What do you want to display on the gauge? Min, max, mean, or something else?

[TaKiMi]

Hi Dennis...

Thank U 4 ur reply...After I learned from ur msg, I try follow ur instructions. I try to put a build waveform function n create a time stamp control at a blok diag. When I started to run the prog..1stly I saw...the date/time data have changed from universal time to current time.Then, to make sure again...I realized that the date/time data have run with the 1st it shown till it stop by elapsed time...So...the situation still same with before.Refer to my vi prog...should I replace the time stamp control to index array with connecting to the to time stamp fuction and connect to t0 after it. Or should i build 1d array before I convert the waveform to dynamic data.Thank U very much....

[Dennis_Knutson]

I don't understand what you mean. You had no time in the table or chart so how can you say it changed from universal time to local time. If you modified your VI, you should post what you did.

[TaKiMi]

oh...i'm sorry dennis..i almost forget these thing.Here, I attached my vi n PNG file. Actually I put the gauges 4 my data from my waveform.I think it can be linked with signal without any prob.So, I didn't know that this function just a scalar input. So refer to my table2 PNG. the date / time did not run properly n stuck with the first time/date data...thank u very much

[Dennis_Knutson]

Are you looking to display fractional seconds as well? I believe that would require you to modify the express VI. Also, since you did not post your VI with any data (you've been asked to do this before), it's impossible to run your VI and see what else might be wrong. I don't know how many data points you are generating with each iteration. You also did not wire up a dt value. The earlier comment I made about the reciprocal was a momentary brain lapse. If you are getting multiple data points with your single VISA Read, I'm not sure how you can determine the dt though. In any case, here's a simple example with an unmodified express VI. You did not post this either so I don't know what you might have changed.

[TaKiMi]

Hi Dennis...

thank you very much...your example was bring me some ideas....Now...my problem was solved and thank you very much again

[aisyah]

Hi Dennis,

I am trying to calculate the time taken for cycles made at the waveform. Given that when an input is fed into the DAQ card for processing, i want to find how long it takes when the input goes LOW/HIGH. My waveform of the input is a sqaure waveform. So, when no squarewaveform is generated, i want to start the timing until the waveform starts to generate again. How can i do that?

Regards,

aisyah.

[Dennis_Knutson]

aisyah,

Since your question has nothing to do with this thread, you really need to post a NEW question. Also, you really should not ask a question of any individual. Lastly, the quesiton is a bit confusing to me. I don't know what kind of hardware you are using, if you are using an analog, counter, or digital input. Posting the code you've written, pictures, etc. will help in determining the solution.