1.3 Expand ANSI C and .NET Development
with Express Technology
Bridging Validation and Test with Common Software Technology
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Interactive versus Automated Measurements/Tests
Interactive
Measurements
• Benchtop
• Non-programmed
Design
Automated
Measurements
• Data Acq, Instr I/O
• Programmed
Validation
Automated
Tests
• Series of meas/tests
• Sequencing (Pass/Fail)
Manufacturing/Repair
For those of you who prefer a text-based approach to automated measurements, National
Instruments also provides text-based programming tools. These can be used to automate
measurements in much the same was as LabVIEW offered in the previous session, but they
adhere to the time-tested constraints of textual programming.
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Text-Based Tools for Automated Test
• LabWindowsTM/CVITM for ANSI C developers
– Advanced data acquisition and analysis libraries for test
and measurement
• Measurement Studio for Microsoft .NET developers
– Add-on test and measurement tools for C#, Visual Basic
.NET and unmanaged Visual C++
Developers who want an open standard like C can use LabWindows/CVI, a development
environment that enables users to create sophisticated GUIs controlled by ANSI C code.
Developers who want to leverage the latest Microsoft computing technology can use
Measurement Studio, a set of add-on tools for the Microsoft Visual Studio .NET languages, as
well as both managed and unmanaged Visual C++ code. Unmanaged code development is for
those who do not want to change their current VC++ 6.0 applications to become a part of
.NET. Managed code is the VC++ 7.0 code that makes use of .NET libraries.
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ANSI C Development with LabWindows/CVI
• C development environment
• Interactive function panels
• Drag-and-drop user interface
• Multi-threading capabilities
• Event-driven programming
• Advanced analysis libraries
• Tight integration with test and
measurement hardware
• Build and distribute executables
LabWindows/CVI 7.0 introduced the workspace window to increase developer productivity.
The workspace window contains the different components of the LabWindows/CVI
environment, such as the source windows, user interface editor, and function tree editor. The
output window region of the workspace window contains various error, debug output, and
results windows. The workspace window also displays the project tree and the library tree. The
project tree provides access to files for each project in the workspace. The library tree provides
access to function panels for the functions in the LabWindows/CVI libraries and loaded
instruments.
The following LabWindows/CVI features are designed to minimize the development effort
required to create engineering and scientific instrumentation applications.
• Function Panels—Function panels are graphical representations of LabWindows/CVI
functions and their parameters that you can use to test function calls and paste them into
your program.
• Automatic Skeleton Code Generation—With LabWindows/CVI CodeBuilder, you can
create skeleton code to help you begin your program and minimize development time.
• Tight Integration between Compiler and Linker—LabWindows/CVI automatically
includes header files required for its internal libraries.
• Run-Time Error Checking—LabWindows/CVI prevents you from overwriting memory
locations and detects errors that other environments might not.
• Interactive Execution of Library Functions—The Interactive Execution window allows
you to test code functionality without having to write a complete program.
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•Instrumentation Libraries—LabWindows/CVI includes instrument driver, data
acquisition, GPIB, VXI, and Analysis libraries.
•Compatibility and Portability—LabWindows/CVI is a complete ANSI C
development environment. In addition, any code you write today will be supported on
all future versions of LabWindows/CVI. Code you develop in the Windows
2000/NT/Me/98 environments can be accessed from other Win32 development
environments. LabWindows/CVI can access third-party DLLs and libraries on these
platforms.
•Add-On Toolkits—Add-on toolkits perform specific sets of tasks to help you build
applications more quickly. Available toolkits include Structured Query Language
(SQL), Image Processing, Statistical Process Control (SPC), Proportional Integral
Derivative (PID) Control, and more.
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• LabWindows/CVI 7.0 – 2003
– Integrated Workspace, tree control, advanced instrument and data acquisition control
• LabWindows/CVI 6.0 – 2001
– ActiveX Container, additional user protection
• LabWindows/CVI 5.5 – 1999
– Tables, multithreading with debugging
• LabWindows/CVI 5.0 – 1998
– New instrument driver technologies
• LabWindows/CVI 4.0 – 1996
– External C/C++ compiler support
• LabWindows/CVI 3.1 – 1995
– Automatic program generation
• LabWindows/CVI 3.0 – 1994
– Introduction of LabWindows/CVI for Windows
• LabWindows for DOS 2.0 – 1991
– GUI tools and memory extender
• LabWindows for DOS 1.0 – 1989
– Introduction
ANSI C
LabWindows/CVI Technology Continuity
LabWindows/CVI first emerged as a set of libraries and a development environment for
creating instrumentation systems using under DOS. Over the years, new features were added
to LabWindows/CVI such as the user interface editor and the integrated workspace
environment, but it remains an ANSI C compiler. This continuity protects you from changes in
technology that occur over time; CVI code written 10 years ago still compiles and runs in the
latest version of LabWindows/CVI.
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Data Acquisition with LabWindows/CVI
• Integrates with all NI measurement
hardware
• Simplifies data acquisition
– Automatic configuration and test panels
– Built-in channel configuration and scaling
– DAQ Assistant
With LabWindows/CVI, you can get up and running quickly to acquire and generate signals
from plug-in boards, USB devices, and Ethernet-based systems. LabWindows/CVI gives you
the ability to easily perform high-speed waveform single-shot and continuous acquisition and
generation, as well as accurate and fast single point analog and digital I/O. These I/O
capabilities, combined with special datatypes and measurement analysis functions, are
specifically designed to obtain the data or measurement you need from your system under test
as quickly and as easily as possible.
LabWindows/CVI also includes functionality to ease data acquisition application
development, including automatic configuration and test panels, the DAQ Assistant, and
built-in channel configuration for scaling and naming raw data.
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Instrument Control with LabWindows/CVI
• LabWindows/CVI communicates easily with instruments
– Instrument drivers
– Instrument I/O Assistant
• Tools for parsing, analyzing, and presenting instrument data
LabWindows/CVI is ideal for acquiring, analyzing, and presenting data—regardless of
whether that data is acquired from a traditional instrument or a data acquisition board.
LabWindows/CVI provides tools to integrate with a wide range of instrument control buses,
including GPIB, USB, Serial, PXI, Ethernet, and VXI. After acquiring the raw data,
LabWindows/CVI has the tools for parsing, analyzing, and presenting the data.
In addition to providing direct I/O support for nearly any instrument that supports a
programmatic interface, National Instruments has hundreds of instrument drivers. An
instrument driver is a LabWindows/CVI library that contains high-level functions that allow
you to control a specific instrument or family of instruments. You may not use an instrument
driver if you only need to send a few commands to your instrument, a pre-existing driver does
not exist, or you do not need to distribute a set of commands to others. Express technology
introduced the Instrument I/O Assistant to provide an interactive tool for connecting to and
controlling instruments, which you will learn more about later in this presentation.
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Measurement Studio for Visual Studio .NET
• Adds native controls and class libraries for test and control
– User interface controls
– Advanced analysis
– Hardware classes
• Comparable data acquisition and instrument control
capabilities to LabWindows/CVI
– Integrated function libraries
– DAQ Assistant, Instrument I/O Assistant
• Fully integrated into Visual Studio environment
Measurement Studio is the most comprehensive suite of native measurement and automation
tools and class libraries for Visual Studio .NET. Measurement Studio dramatically reduces
application development time with wizards, simplified data networking, and .NET user
interface controls designed specifically for test application development.
Code designers interactively define reusable data acquisition tasks and automatically generate
code. Advanced analysis libraries and rich object-oriented hardware APIs, such as data
acquisition and instrument control, enable the development of sophisticated measurement
applications. Through the Measurement Studio add-ons, Visual Studio has data acquisition and
instrument control capabilities similar to those of LabWindows/CVI.
The highly extensible .NET class libraries in Measurement Studio for Visual Studio .NET
deliver unparalleled flexibility. Measurement Studio is completely integrated into the Visual
Studio environment, meaning that the Measurement Studio libraries and Help resources can be
accessed side-by-side with their native Visual Studio counterparts.
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Measurement Studio Data Analysis Tools
• Waveform, array-based, and single-point analysis
• Measurement-oriented analysis libraries
• Hundreds of built-in functions for
inline analysis:
–
–
–
–
–
–
–
Curve fitting and interpolation
FFT and frequency analysis
Signal generation
Mathematics
Probability and statistics
Time and frequency domain analysis
Digital signal processing
Measurement Studio provides hundreds of built-in comprehensive tools designed specifically
for extracting useful information from any set of acquired data and for analyzing
measurements and processing signals. Measurement Studio offers functions that you can easily
incorporate into your programs in order to perform inline analysis and to add decision-making
capabilities to your applications. Available functions include mathematics libraries, advanced
signal processing tools, measurement analysis functions, such as FFT and power spectrum,
signal generation, digital filters, and curve fitting. In this seminar, we will not cover these
analysis functions in depth. For more information, visit ni.com/analysis.
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Measurement Studio UI Controls
• Controls, indicators needed
for test and measurement
– Knobs, dials, buttons,
switches, graphs, and LEDs
• Designed to be extensible
– Developers can use .NET to
add new functionality
Visual Studio does not provide any scientific controls and indicators, but they are often
essential for test and measurement applications.
Measurement Studio includes native .NET controls such as graphs, dials, gauges, LEDs,
sliders, tanks, numeric edits (double data type), and knobs. All of these controls can be
configured to create robust and professional user interfaces that integrate seamlessly with your
.NET application. Attributes such as color, font size, and graph type can be instantly
reconfigured, and you can even rotate, zoom, and pan your graphs at runtime.
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Time-Saving Features in Both Environments
• DAQ Assistant
– Interactive interface to NI-DAQmx architecture
– Customize timing, triggering, and scales
• Instrument I/O Assistant
– Interactive approach to instrument connectivity
– Auto data parsing
– Complete code generation
LabWindows/CVI and Measurement Studio both provide the following productivity tools
(which also are found in LabVIEW) to accelerate development and enable more powerful
DAQ and instrument control applications:
• DAQ Assistant—Provides a user interface to interactively configure measurement tasks,
channels, and scales, specifying timing and triggering characteristics of the measurements.
It is fully integrated into LabWindows/CVI and Visual Studio .NET.
• Instrument I/O Assistant—Provides a user interface to interactively write commands to a
device, read data that the device returns, and specify how to parse the response into a
format relevant to your application. It is fully integrated into LabWindows/CVI and Visual
Studio .NET.
These Assistants simplify writing DAQ and instrument control applications by automatically
generating code from your configuration in either C (LabWindows/CVI) or Visual Basic
.NET, Visual C# and Visual C++ (Measurement Studio).
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Demo – Instrument Control in LabWindows/CVI
In this demonstration, you will see how the Instrument I/O Assistant can be used within
LabWindows/CVI to interactively configure instrument queries, parse the responses and then
generate code to allow developers to quickly create automated instrument control applications.
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Summary
• LabWindows/CVI
– Provides technology continuity from one version to the next
– Easy access to GUI editor, project files, libraries, and debugging
– Integrates with all NI measurement devices
• Measurement Studio for Microsoft Visual Studio .NET
– Most comprehensive suite of .NET add-on measurement tools
– Native .NET controls and class libraries for acquiring, analyzing
and presenting test data
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