queue initialization

[Jamieg]

Hi NI people,

I am using the producer consumer data design.
In my producer loop, I get continuous analog input from a DAQ using the DAQ assistant, this is in the form of dynamic data.
In the consumer loop, I want to analyse the data in batches of say 100 points.
By trial and error, it seems if I set the analog input clock settings to 100 samples (even though acquisition is continuous), and if I initialise with some form of dynamic data, then the consumer loop indeed does grab 100 samples at a time.
But what is the right way to initialise the queue in this case?

I tried wiring a sine waveform generator to it (orange and white wire).  Also tried wiring a simulate signal sine box (blue and white wire).  Both seemed to work.  What is the difference between these 2 approaches? Are these both dynamic data?   Is it not possible to tell it what sort of data to queue rather than creating an example instance?

Regards,
Jamie

[Peter Lamb]

Hi Jamie,

Dynamic data can just be considered a wrapper around some other data type.  There is timing information included in a dynamic data stream which wouldn't exist with simply a waveform data type (orange/white).  As you've discovered, however, these waveform data types can both be used in most cases - dynamic data simply provides you with more information than a non-dynamic type would.  Perhaps the easiest way to differentiate between the types and know instantly what type of data you are dealing with is to open up the context help window.  By simply laying the mouse cursor over any wire you will be shown what type of data it contains.  Once the signal-generating VI has been wired up to the next link in the chain, it should be initialized to the type that was wired to it.

Peter