Is DAQmx Read limited to 9 digital channels?

[AndyO]

I'm trying to read multiple digital channels with DAQmx Read (Digital 1D Wfm NChan NSamp). The output the DAQmx Read vi is a 1D array of digital waveforms. If I put that output through Array to Cluster the resulting cluster seems to be limited to 9 elements, data[0] through data[8]. Is the DAQmx Read output limited to 9 digital waveforms? I'm using Labview 2009.

[Dennis_Knutson · Accepted solution]

No, what you have not done is select the Cluster Size. Nine is the default. Right click on it to change.

Since you would have to change this every time you modify the number of channels, are you sure you want to use clusters instead of just working with an array?

[AndyO]

Thanks. Obviously I haven't used clusters much. I have used Array to Cluster followed by Unbundle or Unbundle By Name as a convenient way to separate waveforms, but it may not be the best way.

[RavensFan]

Converting an array to a cluster to use unbundle to break out the elements of the array is a hack.

You should be using Index Array to get the elements.  You can resize that function so that you can have additional outputs.  You won't even have to wire up any constants for the indices usually.  The top element will be element 0, the next element 1, element 2, and so on down to the bottom of the function.

[AndyO]

Thanks for the tip. Actually the "hack" came from an NI district sales manager.