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National Instruments Confidential

1

LabVIEW Introduction Course

Semester

National Instruments11500 N. Mopac Expressway

Austin, Texas 78759(512) 683-0100

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Graphical Programming for Test,Measurement, and Control

Rapid application development with

Express VIs and easy-to-use

graphical environment

Interactive measurement assistants

and powerful redesigned DAQ

interface for connecting to all types

of I/O

Expanded targeting options fromReal-Time to FPGA to PDA

Localized in French, German, and

Japanese (Korean documentation)

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Readers of Electronic Design name invention of LabVIEW as one

of the Top 50 Milestones for the Electronics Industry

LabVIEW 6.1 receives IAN Automation Excellence Award of

2002

Design News awards LabVIEW 6i Best Computer Productivity

Tool of 2000

LabVIEW 6i chosen the Best of the Bestin the software

category by readers of Evaluation Engineering

LabVIEW Awards

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4

May 2003

January 2002

August 2000

March 1998

February 1996

August 1993

September 1992

January 1990

October 1986

April 1983

LabVIEW 7 Express VIs, I/O Assistants, FPGA/PDA targets

LabVIEW 6.1 Enhanced networking capabilities, analysis

LabVIEW 6iInternet-ready measurement intelligence

LabVIEW 5.0 ActiveX, Multithreading

LabVIEW 4.0 Added professional tools, improved debugging

LabVIEW 3.0 Multiplatform version of LabVIEW

LabVIEW for Windows

LabVIEW 2.0 for Macintosh

LabVIEW 1.0 for Macintosh

LabVIEW project begins

NI LabVIEW: A History of Innovation

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Third-Party Software

Wolfram Research Mathematica Microsoft Excel The MathWorks MATLABand Simulink MathSoftMathCAD Electronic Workbench MultiSim

Texas Instruments Code Composer Studio

Ansoft RF circuit design software Microsoft Access Microsoft SQL Server Oracle

Leveraging Commercial Technologies

Communication Protocols

Ethernet CAN DeviceNet USB IEEE 1394 RS-232

GPIB RS-485

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PC, Mac, Linux, Sun

LabVIEW Everywhere

Networked I/O

PC Boards

Workstation

Handheld

Embedded(FPGA)

Industrial Computer (PXI)

Wireless

Sensor

Tektronix Open Windows

Oscilloscopes

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The LabVIEW Family

NI LabVIEWGraphical Programming Software for Measurement and Automation

LabVIEW Real-Time Module LabVIEW FPGA Module LabVIEW PDA Module LabVIEW Datalogging andSupervisory Control Module

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Acquire, Analyze, and Present

Nearly all test, measurement, and control applications can be

divided into 3 main components: the ability to acquire, analyze, and

presentdata. LabVIEW is the easiest, most powerful tool foracquiring, analyzing, and presenting real-world data.

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Analyzewith LabVIEWLabVIEW includes the following tools

to help you analyze your data: More than 400 measurement analysis

functions for Differential Equations,

Optimization, Curve Fitting, Calculus, Linear

Algebra, Statistics, etc. 12 new Express VIs specifically designed for

measurement analysis, including filtering

and spectral analysis

Signal Processing VIs for Filtering,Windowing, Transforms, Peak Detection,

Harmonic Analysis, Spectrum Analysis, etc.

Powerful measurement

analysis is built in to the

LabVIEW development

environment.

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Presentwith LabVIEW

LabVIEW includes the following

tools to help you present your data: On your machine Graphs, Charts,

Tables, Gauges, Meters, Tanks, 3DControls, Picture Control, 3D Graphs

(Windows Only), Report Generation(Windows Only)

Over the Internet Web PublishingTools, Datasocket (Windows Only),TCP/IP, VI Server, Remote Panels, Email

Enterprise Connectivity Toolset SQLTools (Databases), Internet Tools (FTP,Telnet, HTML)

Presentation withLabVIEW can be done

on your PC or over a

network, or you can take

advantage of additionalapplications such as

DIAdem.

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Course Map

Introduction toLabVIEW

Repetition &Loops

Modular

Programming

VICustomization

Data Acquisition& Waveforms

InstrumentControl

Arrays

Plotting Data

Clusters

Decision Makingin a VI

Strings andFile I/O

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Course Goals

Understand front panels, block diagrams, and connectors/icons

Use the programming structures and data types that exist in

LabVIEW

Use various editing and debugging techniques Create and save your own VIs so you can use them as subVIs

Display and log your data

Create applications that use plug-in data acquisition (DAQ)boards

Create applications that use GPIB and serial port instruments

This course prepares you to:

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Course Non-Goals

Every built-in LabVIEW object, function, or library VI

Analog-to-digital (A/D) theory The detailed operation of the serial port or GPIB bus

How to develop an instrument driver

It is notthe purpose of this course to discuss the

following:

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Lesson 1

Introduction to LabVIEW

TOPICS

LabVIEW EnvironmentFront Panel

Block Diagram

Dataflow Programming

LabVIEW Help and Manuals

Debugging a VI

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Virtual Instruments (VIs)

Front Panel Controls = Inputs

Indicators = Outputs

Block Diagram Accompanying program

for front panel

Components wired

together

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LabVIEW Dialog Box

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Creating a new VI

FileNew VIto open a blank VI

FileNewto open the New dialog box and configure a VI template,global variable, control, etc

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Template Browser

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Menu

File Edit Operate Tools Browse Window Help

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Front Panel Window

Front Panel

Toolbar

Graph

Legend

BooleanControl

WaveformGraph

Icon

Plot

Legend

ScaleLegend

Waveform

GraphOwnedLabel

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Block Diagram Window

WireData

GraphTerminal

SubVI

While LoopStructure

Block

DiagramToolbar DivideFunction

NumericConstant

TimingFunction

Boolean ControlTerminal

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Front Panel and Block Diagram Toolbars

Run button

Continuous Run button

Abort button

Pause/Continue button

Execution Highlighting button

Step Into button Step Over button

Step Out button

Warning indicator

Enter button

Broken Run button

Font ring

Alignment ring

Distribution ring

Resize ring

Reorder ring

Context Help ButtonAdditional Buttons on theBlock Diagram Toolbar

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Tools Palette

LabVIEW automatically selects the tool needed

Available on the front panel and the block diagram

A tool is a special operating mode of the mouse cursor

Use the tools to operate and modify front panel andblock diagram objects

To show the tools palette, select

WindowShow Tools Palette

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Front Panel Controls Palette

Controls PaletteContains the most commonly used controls

All Controls PaletteShows all controls

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Block Diagram Functions Palette

Functions PaletteContains the Express VIs (interactive VIs with

configurable dialog page) and the most commonly

used functions

All Functions PaletteShows all functions

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Palette Tools

Graphical, floating palettes

Subpalettes can be converted to floating palettes Use Palette Options to change palette view from

Express to Advanced

Search Palette Options

Click pushpin to tack down palette

Up to OwningPalette

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Searching for Controls, VIs, and Functions

Press the search button toperform text searches of

the palettes

Click and drag an item

from the search window tothe block diagram or

double-click an item to

open the owning palette

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Build the front panel with controls (inputs)and indicators (outputs)

NumericControl

NumericIndicatorOwned

Labels

IncrementButtons

BooleanControl

BooleanIndicator

Creating a VI Front Panel

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Property Page

Right-click a control orindicator on the front

panel and select

Properties from the

shortcut menu to accessthe property dialog box

for that object

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NodesWires

ControlTerminals

Block DiagramFront Panel

IndicatorTerminals

Creating a VI Block Diagram

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Express VIs, VIs and Functions

Express VIs: interactive VIs with configurable dialog page

Standard VIs: modularized VIs customized by wiring

Functions:fundamental operating elements of

LabVIEW; no front panel or block diagram

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Block Diagram Nodes

Icon Expandable Node Expanded Node

Function Generator VI

Same VI, viewed three different ways

Yellow field designates a standard VI Blue field designates an Express VI

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Block Diagram Terminals

Terminals are entry and exit ports

that exchange information betweenthe panel and diagram

Terminals are analogous to

parameters and constants in text-

based programming languages

Right-click and toggle View As Icon

to change the icon view

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Wiring the Block Diagram

Scalar

Numeric

Boolean

String

2D Array1D Array

Dynamic

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Wiring TechniquesHot Spot

Automatic Wiring

Use Context Help Window when wiring

Right-click wire and selectClean Up Wire

Tip Strips

Automatic wire routing

Right-click terminals

and select Visible

ItemsTerminals

View the terminal connections to a function

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Block diagram executes

dependent on the flow of data;block diagram does NOT

execute left to right

Node executes when data is

available to ALL input terminals

Nodes supply data to all outputterminals when done

Dataflow Programming

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Context Help

To display the Context Help window, select

HelpShow Context Help, press the keys, or pressthe Show Context Help Windowbutton in the toolbar

Move cursor over object

to display help

Connections:

Requiredbold

Recommendednormal

Optional - dimmed

Simple/Detailed Context Help Lock Help More Help

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LabVIEW Help

Click the More Help button in the Context Help window

Select HelpVI, Function, & How-To Help

Click the sentence Click here for more helpin the ContextHelp window.

Contains detailed descriptions of most palettes, menus,tools, VIs, and functions, step-by-step instructions for usingLabVIEW features, links to the LabVIEW Tutorial, PDF

versions of all the LabVIEW manuals and Application Notes,and technical support resources.

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NI Example Finder

To find an example, selectHelpFind Examples

Web-integrated

Search by keyword,

example type, hardwaretype, etc.

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Debugging Techniques

Finding Errors

Click on broken Run button. A window showing the

error appears

Execution Highlighting

Click on Execution Highlighting button; data flow isanimated using bubbles. Values are displayed on

wires.

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Probe

Right-click on wire and select probe and it showsdata as it flows through the wire segment

Breakpoints

Right-click on wire and select Set Breakpoint; pauseexecution at the breakpoint.

Conditional Probe

Combination of a breakpoint and a probe. Right-click on

wire and select custom probe.

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Step Into, Over, and Out buttons for Single Stepping

Click on Step Into button to enable single steppingOnce Single Stepping has begun, the button stepsinto nodes

Click on Step Over button to enable single steppingor to step over nodes

Click on Step Out button to step out of nodes

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Summary Virtual instruments (VIs) have three main parts the front panel, the block

diagram, and the icon and connector pane

The front panel is the user interface of a LabVIEW program and the blockdiagram is the executable code

The block diagram contains the graphical source code composed of nodes,terminals, and wires

Use Express VIs, standard VIs and functions on the block diagram to createyour measurement code. For the most common requirements, use ExpressVIs with interactive configuration dialogs to define your application.

Floating Palettes: Tools Palette, Controls Palette (only when Front PanelWindow is active), and Functions Palette (only when Block Diagram Window isactive)

There are help utilities including the Context Help Window and LabVIEW Help

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Summary Place controls (inputs) and indicators (outputs) in the front panel window

Use the Operating tool to manipulate panel objects. Use the Positioning tool toselect, move, and resize panel objects. Use the Wiring tool to connect diagram

objects

Control terminals have thicker borders than indicator terminals

All front panel objects have property pages and shortcut menus Wiring is the mechanism to control dataflow and produce LabVIEW programs

Broken Run arrow means a nonexecutable VI

Various debugging tools and options available such as setting probes and

breakpoints, execution highlighting, and single stepping

Ti

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Tips Common keyboard shortcuts

Access Tools Palette with -right-click

Increment/Decrement faster using key

ToolsOptions selection set preferences in LabVIEW VI Properties (File menu)

Window s Sun Linux MacOS

Run a VI

Find object

Activate Context Help window

Remove all broken wires

Close the active window

Toggle btwn Diagram/Panel Window

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Lesson 2

Modular Programming

TOPICS

SubVIs

Icon and Connector Pane

Using SubVIs

Creating a SubVI from sections of a VI

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LabVIEW Hierarchy

SubVI

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SubVIs

Function Pseudo Codefunction average (in1,in2, out)

{

out = (in1 + in2)/2.0;

}

SubVI Block Diagram

Calling Program Pseudo Codemain{

average (point1, point2,

pointavg)

}

Calling VI Block Diagram

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Icon/Connector

An icon represents a VI in other block

diagrams

A connector passes data to and receives

data from a subVI through terminals

Icon

Connector

terminals

terminals

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SubVI ExampleCalculating Slope

A VI within another VI is called a subVI

To use a VI as a subVI, create an icon and a connector pane after

building the front panel and block diagram

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Creating the Icon

Icon: graphical representation of a VI

Right-click in the icon pane (Panel or Diagram) Always create a black and white icon

Default Icon Create a custom icon

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Creating the Connector

Right-click the icon(Front Panel only)

C ti th C t ti d

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Creating the Connector- continuedClick withwiring tool

Th C t P

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The Connector Pane

Terminal colors match the data types to which they are connected

Click the terminal to see its associated front panel object

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Using a VI as a SubVI

All Functions Select a VI

Drag icon onto target diagram

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Help and Classifying Terminals

Classify inputs and outputs:

Required Error if no connection Recommended Warning if no connection

Optional No effect if no connection

C t S bVI O ti

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Create SubVI Option

Enclose area to be converted into a subVI

Select Create SubVI from the Edit Menu

S

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Summary

VIs can be used as subVIs after you make the icon and connector

Icon created using Icon Editor Connector defined by choosing number of terminals

Load subVIs using the Select a VI option in the All Functions palette

or dragging the icon onto a new diagram

Online help for subVIs using the Show Context Help option

Descriptions document functionality

Use Create SubVI feature to easily modularize the block diagram

L 3

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Lesson 3

Repetition and Loops

TOPICS

While Loops

For Loops

Accessing Previous Loop Data

Whil L

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While Loops

LabVIEW While Loop Flow Chart Pseudo Code

Repeat (code);

Until Condition met;

End;

Whil L

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While Loops1. Select While Loop 2. Enclose code to be repeated

3. Drop or drag additional nodes and then wire

Select the Loop Condition

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Select the Loop Condition

Click the Conditional Terminal with the Operating tool to

define when the loop stopsDefault: Stop if True

Iteration Terminal Conditional Terminal

St t T l

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Structure Tunnels

Tunnels feed data into and out of structures.

The tunnel is a block that appears on the border; the color ofthe block is related to the data type wired to the tunnel.

When a tunnel passes data into a loop, the loop executes

only after data arrive at thetunnel.

Data pass out of a loop after

the loop terminates.

For Loops

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For Loops

LabVIEW For Loop Flow Chart Pseudo Code

N=100;

i=0;

Until i=N:

Repeat (code; i=i+1);

End;

F L

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For Loops In Structures subpalette of Functions palette

Enclose code to be repeated and/or resize and add nodesinside boundary

Executes diagram inside of loop a predetermined numberof times

Count terminal(Numerical input)

Wait Until Nextms Multiplefunction

W it F ti

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Wait Functions

Wait Until Next

ms Multiple

FunctionsTime

& Dialogpalette

W it F ti

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Wait Functions

Wait (ms)

FunctionsTime& Dialogpalette

Time Delay

FunctionsTime& Dialogpalette

Numeric Conversion

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Numeric Conversion

Numerics default to double-precision (8 bytes) or long integer

(4 bytes) LabVIEW automatically converts to different representations

For Loop count terminal always converts to a long integer

Gray coerciondot on terminal indicates conversion

Numeric Conversion

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Numeric Conversion

LabVIEW chooses the representation that uses more bits.

If the number of bits is the same,LabVIEW chooses unsigned over signed.

To choose the representation,

right-click on the terminal and

select Representation.

When LabVIEW converts floating-point numerics to integers, it

rounds to the nearest integer. LabVIEW rounds x.5 to the

nearest even integer.For example, LabVIEW rounds 2.5 to 2 and 3.5 to 4.

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Additional Shift Register Elements

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Additional Shift Register Elements

Latest value

is passed toright terminal

Right-click theleft terminal toadd newelements

Previous values are available atthe left terminals

Right-click theborder for a

new shiftregister

1 loop ago

2 loops ago

3 loops ago

Feedback Nodes

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Feedback Nodes

Appears automatically in a For Loop or While Loop ifyou wire the output of a subVI, function, or group of

subVIs and functions to the input of that same VI,

function, or group.

Stores data when the loop completes an iteration,

sends that value to the next iteration of the loop, and

transfers any data type

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Initialized Shift Registers & Feedback Nodes

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Initialized Shift Registers & Feedback Nodes

Run Once VI stops execution Run Again

Output = 5Output = 5

Output = 5 Output = 5

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Summary

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Summary

Two structures to repeat execution: While Loop and For Loop

Loop timing controlled using Wait Until Next ms Multiple function,the Wait (ms) function, or the Time Delay Express VI.

Coercion dots appear where LabVIEW coerces a numeric

representation of one terminal to match the numeric representation

of another terminal Feedback nodes and shift registers transfer data values from one

iteration to the next

Use shift registers only when more than one past iteration is

needed

Lesson 4

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Lesson 4

Arrays

TOPICS

Introduction to Arrays

Auto Indexing Arrays

Array Functions

Polymorphism

Arrays

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Collection of data elements that are of same type

One or more dimensions, up to 2 elements per dimension Elements accessed by their index; first element is index 0

31

index

10-element array 1.2 3.2 8.2 8.0 4.8 5.1 6.0 1.0 2.5 1.7

0 1 2 3 4 5 6 7 8 9

2D array

Five row by seven column array of 35 elements

0 1 2 3 4 5 601234

Arrays

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Creating Array Constants

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1. Select Array

Constantshell fromthe Arraysubpalette

2. Place the data object in the array shell

Creating Array Constants

Auto-Indexing

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Loops can

accumulate arrays attheir boundaries with

auto-indexing

For Loops auto-index

by default

While Loops output the

final value by default

Right-click on tunnel

and enable/disable

auto-indexing

Auto-Indexing

Wire becomes thicker

Wire remains the same size

Auto-Indexing Disabled

Auto-Indexing Enabled

Only one value (last iteration)

is passed out of the loop

1D Array

0 1 2 3 4 5

Creating 2D Arrays

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Inner loop creates column elements

Outer loop stacks them into rows

Creating 2D Arrays

1D Array

0 1 2 3 4 5

2D Array

Auto-Index Input

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Auto-Index Input

An array input can be

used to set the For

Loop count terminal

Number of elements

in the array equals

the count terminalinput

Run arrow not

broken

Common Array Functions

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Array Size

Initialize Array



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Array Subset


The Build Array Function

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The Build Array Function

Building a higher dimension array

Concatenate Inputs

Appending an element

default

The Index Array Function

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The Index Array Function

Extracting an Element

Extracting an Element of a Row

Extracting a Row

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Documents

Lesson_1-4