simultaneous audio io with daqmx

[penguin11]

I'm trying to perform real time audio audio processing with with LABVIEW Student 2013 and myDAQ for Aquisition and Generation. The processing will involve manipulating pt by pt signal data. It seems that continuous sampling is proper with a polymorphic setting of single sample , double. I get an error message of "the application is not able to keep up with the aquisition. Increasing the buffer size ...." . Increasing the buffer size only delays the error message. Most important, nothing is written to the channel.

Attached is my DAQmx VI connected without any signal processing. How do I correct my problem and will it allow me to perform

pt by pt signal processing?

Note: I've also tried build a waveform vi feeding into generation, but it ran short of buffer space,  and shut down. The simultaneous audio input output  vi example as well as build a waveform vi produces a 1D array waveform leaving me wondering how to process pt by pt.

Thanks. 

[Bob_Schor · Accepted solution]

You have set up your myDAQ to sample 1000 points and then deliver them to you.  I'm not sure why you are changing the Buffer Size inside the loop (and can't see what you are changing it to), but you then proceed to read a single sample (out of the 1000 in the buffer) before calling for another read.  Woefully inefficient.

Without worrying (yet) about how you are going to process the data, why not concentrate on just getting it?  Leave your buffer size at 1000, read 1 Channel N Samples to get the entire buffer in.  As you are clearly just beginning to learn how to do things, don't be so ambitious -- simplify your code to do only Analog Input and get that working.  Once it does, see if you can hand off the Analog buffer of 1000 points to Analog Out (I think the myDAQ can do buffered output ...).

Bob Schor

[penguin11]

Thanks Bob,

I'll try that approach.

Penguin11