How to use LabVIEW Ihor Korolov February 2011. Contents What is LabVIEW? How does LabVIEW work?...

How to use LabVIEW

Ihor Korolov

February 2011

Contents

What is LabVIEW?

How does LabVIEW work?

Block diagramFront panelPalettes

Data flow programming. Functions.

LabVIEW Programming Structures (Formula, Case structure …)

What is a subVI? Using a VI as a subVI.

How to use LabVIEW with data acquisition (DAQ) software

Measurements and automation explorer (MAX)

I. Korolov: How to use LabVIEW

What is LabVIEW?

I. Korolov: How to use LabVIEW

LabVIEW – Laboratory Virtual Instrument Engineering Workbenchis a graphical (visual) programming from National istruments (NI).

The purpose is automating the usage of processing and measuring equipment in any laboratory setup.

Originally released for the Apple Macintosh in 1986, the graphical language at the heart of LabVIEW is called "G".

uses icons instead of lines of text to create programs

Dataflow programming languageC language

Cross-platform

The graphical approach of LabVIEW allows non-programmers to build programs by dragging and dropping virtual representations of lab

equipment with which they are already familiar.

Price

LabVIEW Professional Development System

I. Korolov: How to use LabVIEW

Desktop PC

Laptop

PDAhttp://www.ni.com/labview/buy/

High-SpeedDigitizers

High-ResolutionDigitizers and DMMs

Multifunction Data Acquisition

DynamicSignal Acquisition

Digital I/OInstrumentControl

Counter/Timers

MachineVision

Motion Control

Distributed I/O andEmbedded Control

Laptop PC PDADesktop PCPXI Modular Instrumentation

Signal Conditioningand Switching

Unit Under Test

LabVIEW

I. Korolov: How to use LabVIEW

www.ni.com

How does LabVIEW work?

I. Korolov: How to use LabVIEW

How does LabVIEW work?

I. Korolov: How to use LabVIEW

How does LabVIEW work?

I. Korolov: How to use LabVIEW

Front panel Block Diagram

Ctrl+E

Block diagram toolbar

Reorder objectsRun

Continuous run

Pause

Stop

Debugging features

Clean Up diagram

How does LabVIEW work?

I. Korolov: How to use LabVIEW

LabVIEW Front panel

Used to display Controls or Indicators

How does LabVIEW work?

I. Korolov: How to use LabVIEW

LabVIEW Block Diagram

- Actual program - Invisible to user- Read left to right

Example LP

How does LabVIEW work? Palettes

I. Korolov: How to use LabVIEW

Front panel

Controls palette

Tools palette

Block Diagram

How does LabVIEW work? Tools palette

I. Korolov: How to use LabVIEW Example

Operating Tool

Positioning/Resizing Tool

Labeling Tool

Wiring Tool

Shortcut Menu Tool

• Floating Palette• Used to operate and modify front

panel and block diagram objects.

Scrolling Tool

Breakpoint Tool

Probe Tool

Color Copy Tool

Coloring Tool

Automatic Selection Tool

Data flow programming

I. Korolov: How to use LabVIEW

Data flow programming

I. Korolov: How to use LabVIEW

If you put a control (or indicator) on the front panel

LabVIEW automatically creates a correspondingcontrol (or indicator) terminal on theBlock Diagram

Example FP TB

Data flow programming. Functions.

I. Korolov: How to use LabVIEW

View as icon

Click and Ctrl+H“Add” function

wire

Example2,3

Data flow programming. Functions.

I. Korolov: How to use LabVIEW Example

Data flow programming. Wires

I. Korolov: How to use LabVIEW

Some of basic wires used in block diagrams

Data type Color

Floating-point orange

Integer blue

Boolean green

String Pink/purple

Dynamic Dark blue

Broken wires

The wire connects more than one data source

You have connected two terminals of different types

Data flow programming. Functions

I. Korolov: How to use LabVIEW Example

Data flow programming. Functions

I. Korolov: How to use LabVIEW

Polymorphism

Array Arithmetic Operations

Programming structures

I. Korolov: How to use LabVIEW

LabVIEW Programming Structures

I. Korolov: How to use LabVIEW

For loop

Right click

From 0 to N-1

Example For Loop

LabVIEW Programming Structures

I. Korolov: How to use LabVIEW

While loop

Repeats the sub diagram inside the loop until the conditional terminal receives a particular Boolean value

Auto-indexed tunnel

Loop tunnel

Shift register

Timed While loop

Example WhileL

LabVIEW Programming Structures

I. Korolov: How to use LabVIEW

Case structure

Example

LabVIEW Programming Structures

I. Korolov: How to use LabVIEW

Flat sequence structure

Stacked sequence structure

1 2 3

12

34

Sequence structures are used to ensure a subdiagram executes after or before another subdiagram

LabVIEW Programming Structures

I. Korolov: How to use LabVIEW

Use global variables to access and pass data among several

VIs

Use local variables to read or write to one of the controls or indicators on the front

panel of a VI.

Local variables Global variables

Example

LabVIEW: Wait statements

I. Korolov: How to use LabVIEW

Wait Until Next ms Multiple functionWait (ms) function

Pre-loopcode

Loop code

LabVIEW: Graphs

I. Korolov: How to use LabVIEW

Waveform GraphWaveform Graph – Plot an array of numbers against their indices – Plot an array of numbers against their indicesXY GraphXY Graph – Plot one array against another – Plot one array against anotherDigital Waveform GraphDigital Waveform Graph – Plot bits from binary data – Plot bits from binary data

Graph properties

Example Graph

LabVIEW: File I/O

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Write to a File Read from a File

Writing to LVM fileWriting to LVM file Reading from LVM fileReading from LVM file

Write/Read LabVIEW Measurements file

Example File I/O

SubVI

I. Korolov: How to use LabVIEW

What is a subVI? Using a VI as a subVI.

I. Korolov: How to use LabVIEW

What is a subVI?

A SubVi is a stand VI that can be called by other VI and it is similar to an individual function.

AdvantagesModular

Easier to debugDon’t have to recreate codeRequire less memory

What is a subVI? Using a VI as a subVI.

I. Korolov: How to use LabVIEW

How to create a subVI?

A SubVi is a stand VI that can be called by other VI and it is similar to an individual function.

Create/Edit the Icon Create the Connector Assign Terminals to controls and indicators Add description (optional) Save the VI Insert the VI into a Top Level VI

1 Create/Edit the Icon

Right-click on the icon in the block diagram or front panel

What is a subVI? Using a VI as a subVI.

I. Korolov: How to use LabVIEW

2 Create the ConnectorRight click on the icon pane (front panel only)

3 Assign Terminals to controls and indicators

r

4 Documentation (VI properties)

5. Save the VI

6. Insert the VI into a Top Level VI

Example

Data acquisition

I. Korolov: How to use LabVIEW

How to use LabVIEW with DAQ software

I. Korolov: How to use LabVIEW

• Data acquisition (DAQ)

• Connecting Signals

• Simple DAQ application

Sensors

Terminal Block

DAQ device

Fundamental task of a DAQ system is to measure or generate real-world physical signals

Measurements and automation explorer (MAX)

I. Korolov: How to use LabVIEW

Measurement & Automation Explorer (MAX) provides access to all your NI DAQ, GPIB, IMAQ, IVI, Motion, VISA, and VXI devices. Here can configure your NI hardware and software, add new channels, interfaces, and virtual instruments, execute system diagnostics, and view the devices and instruments connected to your system.

Configuration tree Configuration View Task list

MAX is the primary configuration and testing utility that is available for the DAQ device

MAX

How to use LabVIEW with DAQ software

I. Korolov: How to use LabVIEW

Traditional NI-DAQSpecific VIs for performing:• Analog Input• Analog Output• Digital I/O• Counter operations

NI-DAQmxNext generation driver: • VIs for performing a

task• One set of VIs for all

measurement types

DAQ assistant Measurement type can be:• Analog Input• Analog Output• Counter Input• Counter Output• Digital I/O

How to use LabVIEW with DAQ software

I. Korolov: How to use LabVIEW

Ni USB 6501

Quickly and easily program the DAQ deviceCreates a local taskMost applications can use the DAQ Assistant

DAQ assistant

Example DAQ

How to use LabVIEW ? Tips and tricks

I. Korolov: How to use LabVIEW

GPIB Communication and Configuration

Virtual Instrument Software Architecture (VISA)Serial Port Communication

Instrument Drivers (How to create and use *.dll in LabVIEW)

Application control (property node and invoke node)

How to execute a system command

Remote panel connection manager and Web publishing tool

…

Tips and tricks (3.03.2011)

Köszönöm for your attention!

I. Korolov: How to use LabVIEW