DAQmx - how does it multithread?

Howdy,
i am using DAQmx in VC++. my question is how does DAQmx run threads? In traditional DAQ, when you perform an acquisition, it runs as a separate parallel process(if i remember right). Is it the same with DAQmx? or does it run tasks as threads within the calling application's process itself?
thanks in advance,
vikram

Here is some information in the following white paper that I thought would be useful to you.
http://zone.ni.com/devzone/conceptd.nsf/webmain/5df09082448cbcf886256e7c0078ee9c
NI-DAQmx driver software is designed to help you significantly improve performance by exploiting the computer processor power and the memory structure of operating systems. NI-DAQmx driver software uses a multithread application structure to maximize computer processor power and implements memory-mapped registers to produce unprecedented concurrent and single-point I/O performance. As a result, you can experience up to 40 times better performance when you perform a concurrent I/O operation and 20 times faster execution speed when you perform a single-point I/O operation.
NI-DAQmx is an innovative driver software architecture that incorporates multithread technology. With multithreaded DAQ operations, you can perform an I/O operation independently in a separate thread. This guarantees faster execution speeds when you perform concurrent operations. Performing a concurrent operation, such as generating a continuous analog output waveform while acquiring a continuous analog input signal, in a single-threaded environment can be extremely challenging and can yield slow performance unless you employ complicated programming and timing techniques. Because NI-DAQmx driver software is multithreaded, it guarantees the simultaneous operation of analog input acquisition and analog output generation by assigning a separate thread to each operation. This eliminates the need to develop a complicated program to create an optimized concurrent operation. You can implement a multithreaded DAQ operation simply by using the NI-DAQmx Library.
Take an example of a synchronized AI/AO operation example program. You do not have to manually allocate separate threads for each analog input and analog output operation. The NI-DAQmx functions allocate the threads automatically. Therefore, with the NI-DAQmx Library, you can develop a multithreaded DAQ application without spending time implementing the details.
Thank you
Nandini Subramaniam
Applications Engineer
National Instruments

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DAQmx - how does it multithread?

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