The only record you have that is related to a trigger is the single record from the DAQmx Read. The other record is from the 'Waveform Buffer Generation' VI that you have. Why would you expect this record to have the same timestamp? The timestamp is created when you run the VI. It is not magically updated when you execute the DAQmx Write.
Your expectation is just wrong the way you are doing things. I don't understand how to make the explanation any simpler. You have decided not to actually do a capture of the waveform you are generating even though I have suggested that. That is the only way to truly show the actual phase difference. It is, to me, quite basic that you would want to to that. I have said over and over again that the waveform you are plotting as the 'output' is not the actual output. It is just an array that you created with a different sample rate and number of samples than what you setting the hardware to.
I was quite confused.Do you suggested me this example? Do you mean I didn't acquire the real output voltage? Could you tell me how can I get real waveform?Could you give me a example?Maybe that would explain why 1 cycle output 5 cycle input in the same graph
Of course you aren't acquiring the real output. You've defined only a single channel for your DAQmx Read. That's a pretty basic concept. What is confusing about my suggestion to use one of your spare input channels and connecting it to the signal you are outputting?
As Michael and Dennis have mentioned, you are able to synchronize your input and output data with triggers. I have included a link below to a community example that you can look through that may provide you more insight.
Do you think my vi could get input and output data at the same time?But,why the value of them are defferent in their records?
Yun
I've told you over and over again why the timestamps are different - two different sources of tiiming data. You keep ignoring what I've said about that and the very simple solution to get the exact same timestamp for both signals and a very accurate representation of the actual phase difference. I'm done. Do what I suggested or explain why you won't do it but don't keep asking the same silly question again and again.
The best way to deal with such silly question or silly person is not only telling,but also showing.Would you like to show me exactly where are the problem and how to correct them.I think It's very simple for you to correct my vi . But,It's very difficult to work out for me.
