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  • Virtual instruments (VIs) contain three main components-the front panel, the block diagram, and the icon and connectorpane.
  • The front panel is the user interface of a VI and specifies the inputs and displays the outputs of the VI.
  • The block diagram contains the graphical source code composed of nodes, terminals, and wires.
  • Use the Tools palette to create, modify, and debug VIs. Press the Shift key and right-click to display a temporary version of the Tools palette at the location of the cursor.
  • Use the Controls palette to place controls and indicators on the front panel. Right-click an open space onthe front panel to display the Controls palette.
  • Use the Functions palette to place VIs and functions on the block diagram. Right-click an open space onthe block diagram to display the Functions palette.
  • Use the Search button on the Controls and Functions palettes to search for controls, VIs, and functions.
  • All LabVIEW objects and empty space on the front panel and block diagram have associated shortcut menus, which youaccess by right-clicking an object, the front panel, or the block diagram.
  • Use the Help menu to display the Context Help window and the LabVIEW Help , which describes most palettes, menus, tools, VIs, functions, andfeatures.
  • Select Help>>Search the LabVIEW Bookshelf to display the LabVIEW Bookshelf , which you can use to search PDF versions of all the LabVIEW manuals and Application Notes .
  • You build the front panel with controls and indicators, which are the interactive input and output terminals of theVI, respectively.
  • Control terminals have a thicker border than indicator terminals. To change a control to an indicator or to changean indicator to a control, right-click the object and select Change to Indicator or Change to Control from the shortcut menu.
  • The block diagram is composed of nodes, terminals, and wires.
  • The broken Run button appears on the toolbar to indicate the VI is broken. Click the broken Run button to display the Error list window, which lists all the errors.
  • Use execution highlighting, single-stepping, probes, and breakpoints to debug VIs by animating the flow of datathrough the block diagram.

Tips and tricks


  • Frequently used menu options have equivalent keyboard shortcuts. For example, to save a VI, you can select File>>Save or press the Ctrl-S keys. Common keyboard shortcuts include the following:
  • Ctrl-r

    Runs a VI.
  • Ctrl-e

    Toggles between the front panel and block diagram.
  • Ctrl-h

    Toggles display of the Context Help window.
  • Ctrl-b

    Removes all broken wires.
  • Ctrl-f

    Finds VIs, globals, functions, text, or other objects loaded in memory or in a specified listof VIs.
  • To increment or decrement numeric controls faster, use the Operating or Labeling tools to place the cursor in the control and press the Shift key while pressing the up or down arrow keys.
  • You can disable the debugging tools to reduce memory requirements and to increase performance slightly. Select File>>VI Properties , select Execution from the top pull-down menu, and remove the checkmark from the Allow Debugging checkbox.


  • Click the Show Context Help Window button on the toolbar to display the Context Help window. Use the Context Help window to determine which terminals are required. Required terminalsare bold, recommended connections are plain text, and optional connections are dimmed.
  • Press the spacebar to toggle the wire direction.
  • To move objects one pixel, press the arrow keys. To move objects several pixels, press the Shift key while you press the arrow keys.
  • To cancel a wire you started, press the Esc key, right-click, or click the terminal where you started the wire.
  • Use the tip strips that appear as you move the Wiring tool over terminals.
  • Display the connector pane by right-clicking the node and selecting Visible Items>>Terminals from the shortcut menu.
  • You can bend a wire by clicking to tack the wire down and moving the cursor in a perpendicular direction. To tackdown a wire and break it, double-click.
1. Tack Down a Wire by Clicking, 2. Tack and Break the Wire by Double-clicking


  • Use the following shortcuts to create constants, controls, and indicators:
    • Right-click a function terminal and select Create>>Constant , Create>>Control , or Create>>Indicator from the shortcut menu.
    • Drag controls and indicators from the front panel to the block diagram to create a constant.
    • Drag constants from the block diagram to the front panel to create a control.
  • To duplicate an object, press the Ctrl key while using the Positioning tool to click and drag aselection.
  • To restrict an object's direction of movement horizontally or vertically, use the Positioning tool to select the object and press the Shift key while you move the object.
  • To keep an object proportional to its original size as you resize it, press the Shift key while you drag the resizing handles or circles.
  • To resize an object as you place it on the front panel, press the Ctrl key while you click to place the object and drag the resizing handles or circles.
  • To replace nodes, right-click the node and select Replace from the shortcut menu.
  • To display the block diagram of a subVI from the calling VI, press the Ctrl key and use the Operating or Positioning tool to double-click the subVI on the block diagram.
  • To display the front panel of a subVI from the calling VI, use the Operating or Positioning tool to double-click the subVI on the block diagram. You also canselect Browse>>This VI's SubVIs .
  • After you type a label, press the Enter key to end text entry.
  • To add items quickly to ring controls and Case structures, press the Shift-Enter keys after each item. Pressing Shift-Enter accepts the item and positions the cursor to add the next item. Refer to Making Decisions in a VI for more information about Case structures.
  • To copy the color of one object and transfer it to a second object without using a color picker, use the Color Copy tool to click the object whose color you want to copy. Use the Coloring tool to click the object to which you want to apply thecolor. You also can copy the color of one object by using the Coloring tool and pressing the Ctrl key.
  • Select Edit>>Undo if you make a mistake.
  • To create more blank space on the block diagram, press the Ctrl key while you use the Positioning tool to draw a rectangle on the block diagram.


  • When single-stepping, use the following keyboard shortcuts:
  • Ctrl-down arrow

    Steps into a node.
  • Ctrl-right arrow

    Steps over a node.
  • Ctrl-up arrow

    Steps out of a node.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Labview graphical programming. OpenStax CNX. Apr 09, 2015 Download for free at https://legacy.cnx.org/content/col11408/1.2
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