Advantages of NI-DAQmx

This document highlights a few of the advantages of the new NI-DAQmx driver (part of NI-DAQ 7) over Traditional NI-DAQ. A list of operating systems, software, and hardware that NI-DAQ 7 supports is found in the link at the bottom of this document.

Improved State Model

NI-DAQmx defines and enforces a state model, which eliminates unnecessary reconfigurations of input limits, timing, triggering, and accessories. This improvement significantly increases overall performance, but is most noticeable in single-point software-timed analog input. The link below contains examples that illustrate the significant single-point software-timed speed improvement in NI-DAQmx over Traditional NI-DAQ.

Another key part of the performance improvement of single-point software-timed I/O is memory-mapped registers. For more information on memory-mapped registers, see the Waveform and Single-Point I/O in NI-DAQ 7 Application Note below.

See Also:
NI-DAQ 7 vs. Traditional NI-DAQ Performance Improvements
Waveform and Single-Point I/O in NI-DAQ 7

Multithreaded Driver

Because NI-DAQmx is a multithreaded driver, programming concurrent I/O operations is much easier. Two operations that do not use the same functional subsection (counters, analog input, analog output, digital I/O) of a device can execute simultaneously. The link below contains examples that illustrate how the multithreaded NI-DAQmx driver improves the performance of concurrent operations.

See Also:
NI-DAQ 7 vs. Traditional NI-DAQ Performance Improvements

Robustness in Exceptional Conditions

Traditional NI-DAQ can have difficulty handling exceptional conditions like abnormal process termination. NI-DAQmx defines and enforces policies for such conditions and is much more robust than Traditional NI-DAQ.

Simplified Synchronization

Synchronizing devices and operations in Traditional NI-DAQ can be fairly complex. Typically, you must explicitly route signals over the RTSI bus or through PFI lines. NI-DAQmx eliminates the need to route signals. You simply choose the signal upon which you would like to synchronize and NI-DAQmx does all the routing for you.

Decreased LabVIEW Diagram Clutter

With NI-DAQmx, the diagram does not contain configuration information. Instead of putting configuration information in the program, you use the DAQ Assistant to configure your measurement tasks and channels. This results in:
- Increased development productivity
- Less expensive code, debug, and test cycles
- Ability to get started quickly with difficult tasks
- Cleaner, less cluttered diagrams.

To illustrate the last point, compare the code required for an operation to acquire N scans with an external scan clock and a digital trigger. In Traditional NI-DAQ, the code required looks like this:


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The code for the same operation in NI-DAQmx could look like this:




For more information on the DAQ Assistant, refer to the DAQ Assistant Help and the links below.

See Also:
DAQ Assistant
Using the DAQ Assistant to Automatically Generate LabVIEW Code
NI-DAQ 7 Measurement-Ready Virtual Channels and Configuration Services

Smooth Transition from Easy to Advanced Programming

The NI-DAQmx API exposes increasing power and complexity through interoperable layers. This means that if you decide at the last minute to include an advanced feature in your operation (like a trigger), you don't have to start over. Notice how much easier it is to change an internally clocked acquisition to externally clocked in NI-DAQmx:


Traditional NI-DAQ - Internally Clocked

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Traditional NI-DAQ - Externally Clocked


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NI-DAQmx - Internally Clocked




NI-DAQmx - Externally Clocked

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See Also:
KnowledgeBase 2XDHH7BG: Overview of Hardware and Software Support in DAQmx

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