LabVIEW in 3 Hours
What is Test & Measurement?
Acoustic
Quality
Keypad
Functionality
Sound
Quality
RF Signal
Analysis
LCD
Testing
Battery Test
EngineeringTelecom
– Industries
Manufacturing
Electronics
Automotive
Test
Industries
Semiconductor
Chemical Processing
Aerospace
Transportation
Military
Biomedical
Instrumentation
Instrumentation
Data Acquisition
Virtual Instrumentation
Hardware and
Driver Software
Application
Software
Virtual Instrumentation Architecture
LabVIEW
Instrument / Data Acquisition Drivers
GPIB/Serial
and VXI
Data Acquisition and
Signal Conditioning
Modular
Instrumentation
PXI/CompactPCI
Vision
Distributed I/O
PLCs
Section I – The LabVIEW Environment
• LabVIEW terms
• Components of a LabVIEW application
• LabVIEW programming tools
• Creating an application in LabVIEW
LabVIEW Programs Are Called Virtual
Instruments (VIs)
LabVIEW Programs Are Called Virtual
Instruments (VIs)
2 Work areas:
1. Front Panel
Controls = Inputs to
the computer
LabVIEW Programs Are Called Virtual
Instruments (VIs)
2 Work areas:
1. Front Panel
Controls = Inputs to
the computer
Indicators = Outputs
from the computer
LabVIEW Programs Are Called Virtual
Instruments (VIs)
2 Work areas:
1. Front Panel
Controls = Inputs to
the computer
Indicators = Outputs
from the computer
2. Block Diagram
Instruction set for
controls, indicators
“Source Code”
VI Front Panel
Panel Toolbar
Pull-down
menu
Boolean
Control
Double
Indicator
Waveform Graph
VI Block Diagram
Pull-down
menu
Thermometer
Terminal
Data
Acquisition
Function
Temperature
Indicator
Delay
While Loop
Stop Loop
Terminal
Stop Button
Terminal
Controls and Functions Palettes
Controls Palette
Functions Palette
(Front Panel Window)
(Block Diagram Window)
Graphical, floating palettes
Used to place controls & indicators on
the front panel, or to build the block
diagram
Tools Palette (Front Panel)
Operating Tool
Positioning/Resizing Tool
Labeling Tool
Coloring Tool
Tools Palette (Block Diagram)
Automatic Selection
Operating Tool
Wiring Tool
Positioning/Resizing Tool
Breakpoint Tool
Labeling Tool
Probe Tool
Coloring Tool
Status Toolbar
Run Button
Continuous Run Button
Additional Buttons on the
Diagram Toolbar
Abort Execution
Pause/Continue Button
Text Settings
Align Objects
Distribute Objects
Reorder
Execution Highlighting
Button
Step Into Button
Step Over Button
Step Out Button
Status Toolbar
Run Button
Continuous Run Button
Additional Buttons on the
Diagram Toolbar
Abort Execution
Pause/Continue Button
Text Settings
Align Objects
Distribute Objects
Reorder
Execution Highlighting
Button
Step Into Button
Step Over Button
Step Out Button
Open a Virtual Instrument
Basic Spectral Measurement.vi
Template Browser
Create a New VI
Creating a VI – Front Panel
Front Panel Window
Creating a VI – Front Panel
Front Panel Window
Creating a VI – Block Diagram
Front Panel Window
Block Diagram
LabVIEW’s Context Help
Creating a VI – Adding Functions
Creating a VI – Adding Functions
Creating a VI – Wiring
Wire attachment points
(nodes) flash when the
wiring tool is passed over
Right Click
wiring tool
Node Terminals
(communication
ports)
Creating a VI – Adding Functions
Creating a VI – Adding Functions
Express Functions
Same overall functionality
Section II
• What is a subVI?
• Creating a subVI
• Using a VI as a subVI
SubVIs
LabVIEW is modular
• Any VI can be used as a subroutine (or
subVI) to other programs
• Advantages
– Modular
– Easier to debug
– Don’t have to recreate code
Creating a SubVI
1.
2.
3.
Create code
Select code for use in
subVI
Click Edit-Create subVI
Editing a SubVI
Insert the SubVI into a Top Level VI
Accessing user-made subVIs
Functions >> Select a VI
Or
Drag icon onto target diagram
Create SubVI from your code
View your subVI
Section III – Data Acquisition
• Data acquisition (DAQ) basics
• Connecting Signals
• Simple DAQ application
DAQ – Data Acquisition
• Plug-in board for a computer with:
– Analog input channels
– Analog output channels
– Counters
– Digital I/O
• Controlled by a suite of LabVIEW VIs
Functions>>Data Acquisition
DAQ – Data
Acquisition
Hardware Connections
BNC-2120
SC-2075
SCB-68
Channel Connections
Motor
Signal
Single-Ended
Ground
Battery
Measurement
+ Signal 1
Differential
- Signal 2
Measurement
Analog Signals
Data Acquisition System
1.659487387 volts
ADC
1010100111110
Digital Signals
Measurement & Automation Explorer
Channel Connections
• Single-Ended Mode: ACHx
and AIGND used to connect
signal to channel x
• Differential Mode: ACHx,
ACHx+8 used to connect
signal to channel x
Section IV – Loops and Charts
• For Loop
• While Loop
• Charts
• Graphs
Loops
• While Loops
– Terminated by condition
– Always Runs Once
– Delay between iterations
may be added
• For Loops
– Terminate after N iterations
– N specified on block diagram
Loops (cont.)
1. Select the loop
2. Enclose Code to
Repeat
While Loop
Charts and Graphs
•Waveform Charts display a history of values over time
- Strip Chart (continuous scrolling)
- Scope Chart (repeatedly redraws over the same region)
- Sweep Chart (redraws curve to the right of the old curve)
•Waveform Graphs and X-Y Graphs
- Wavefrom Graphs plot Y for regular increments of X
- X-Y Graphs plot Y vs. X for any X-Y sets (non-regular)
Charts
Waveform chart – special numeric indicator
that can display a history of values
Controls >> Graphs >> Waveform Chart
Wiring Data into Charts
Single Plot Charts
Multiplot Charts
Combining data onto one graph
File I/O
Using The
LVM
Express
Function
File I/O Using Traditional Functions
Easy File
I/O VIs
•Read/write to
spreadsheet file
•Read/write characters
to file (ASCII)
•Read lines from file
•Read/write binary file
Conclusion
• See www.ni.com for more help, examples