multiple channels, multiple waveform graph

[acewong7]

Hello, there! I am trying to read four signals from four channels on DAQ device. I need to show the first two signals on one diagram and the other two on another diagram. So I wrote a simple VI as I attached. It gives me an error message like the picture I attached. Does anyone know how to debug this VI? I have come up with some very stupid idea to solve this problem, I can wire all this four AI Voltage VI together then go through Timing VI, then Logging VI, then Read VI, then I can connect the data terminal of this Read VI to an Index Array VI, so that I can do the following as the third Pic I attched. I have not tried this yet, but I want to find out some better method. (Maybe like the VI I wrote, it is very intuitive for people to understand) 

[acewong7]

Oh,,, forgot to say: Thank you for any help and suggestions! 

[NarayananK]

I have modified the VI to perform continous data aquisition, the error could be due to continuous starting and stopping of the task.

you may want to refer this link

http://digital.ni.com/public.nsf/allkb/485201B647950BF886257537006CEB89

[acewong7]

Hello, NaruF1, I rerun the program as you modified. It gives me the same error message. Please see the picture I attached. Thanks 

[NarayananK]

Hi,

We need more information on detail of the DAQ device in use? I suspect this error could be due to sharing of single onboard clock.

However, If all the channels could be coupled into a single task (This should be possible since there are not configuration difference between acquisition for different channel)

Then you could use the Simple Delete from Array Function with Index=2 and length =2 available to seperate the waveform array and display them on two seperate graph Indicator. (attached modified vi)

[Edna-S]

Take a look at the following forum. It talks about the error that you are getting.

http://forums.ni.com/t5/Multifunction-DAQ/Error-50103-occurred-at-DAQmx-Start-Task/m-p/2236952

http://forums.ni.com/t5/Academic-Hardware-Products-NI/Labview-Error-50103-occurred-at-DAQmx-Start-Ta...