Error of Get date/time in seconds function

[Sangkyu]

I change name of VI.

[GerdW]

Hi Sangkyu,

please don't create double threads for the same problem!

My data is 10 Channel , Fs=500Hz, T=1.024s square wave.

According to your VI you only read 5 channels…

(You should have given this information right from the beginning - before I merged your threads!)

When the sampling frequency is given by your DAQ device then why do you rely on your computers internal clock?

Why not create a waveform from your samples and set its dt to 0.002???

Hint:

- When you really worry about timing in your loops you should NOT update a chart inside this loop. Use a producer-consumer-scheme to separate DAQ/serial communication from data analyzing from saving from display…

- When you use the same condition to drive 5 different case structures you should put their content into one bigger case structure…

- You don't need to wire the index inputs of IndexArray when you start to read elements from index 0…

[Sangkyu]

sorry, I have 5 channel. I was confused.

I want to sync my DAQ system and android smart phone.

But, My DAQ doesn't have Global clock.

So, I think I record the Global time in Labview and Andoid respectively.

After saving data, I merge each data using Global time.

I sorely want to save time using 'Get date/time in seconds' function when finish the receiving VISA data.

I try one thing or another, but It does not improve.

[GerdW]

Hi Sangkyu,

I want to sync my DAQ system and android smart phone. But, My DAQ doesn't have Global clock.

What kind of DAQ do you use?

So, I think I record the Global time in Labview and Andoid respectively.

That's ok - as long as both "computers" use the same time base/clock…

I sorely want to save time using 'Get date/time in seconds' function when finish the receiving VISA data.

I already suggested to build a waveform using dt=0.002. You can also set a t0 in your waveform - I would use the start time of your measurement…

I try one thing or another, but It does not improve.

What did you try?

What did not improve?

[Norbert_B]

Sorry to say, but "Windows", "Android", "VISA" (serial?) and "2ms synchronization" do not fit together.

Regardless of your technical questions, i am confident that you have an expectation against these things which will not be met.

It already requires sophisticated ways to synchronize time stamps on RT targets (which do cost some money), but that is not likely to work properly on Windows and Android (for OS system timestamping).

See more about synchronization.

What is the purpose of this application? Why do you have two computers acquiring data which have to be synchronized against each other?

@Gerd: i think he refers to myDAQ.