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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

Differences between microeconomics and macroeconomics
tatiana Reply
what is Economics
Ebem Reply
the branch of knowledge concerned with the production, consumption, and transfer of wealth and has Influence by sociology!!!!
Economics is the study of how humans make decisions when they want to fulfil their requirements and desires for goods, services and resources.
Economics is the study how humans make decisions in the faces of scarcity.
economic is the study of how human make decision in the fact of scarcity.
Economics is a social science which study human behavior as a relationship between earn and scarce mean which have alternative uses
what is market structure
market structure in economics depicts how firms are differentiated and categorised based on types of goods they sell and how their operations are affected by external factors and elements.
what is economic theory
what is demand
Gooluck Reply
demand is the willingness to purchase something
demand is the potential ability or williness to purchases something at a particular price at a given period of time..
Demand refers to as quantities of a goods and services in which consumers are willing and able to purchase at a given period of time. Demand can also be defined as the desire backed by ability to purchase .
what is demand
John Reply
is the production of goods in scarcity
Demand refers to as quantities of a goods and services in which consumers are willing and able to purchase at a given period of time.
what is demand of supply
music Reply
What is the meaning of supply of labour
Anthonia Reply
what is production?
Elizabeth Reply
Production is basically the creation of goods and services to satisfy human wants
under what condition will demand curve slope upward from left to right instead of normally sloping downward from left to right
Atama Reply
how i can calculate elasticity?
Tewekel Reply
What is real wages
Emmanuella Reply
what are the concept of cost
Tabitha Reply
what is the difference between want and choice
Grace Reply
Want is a desire to have something while choice is the ability to select or choose a perticular good or services you desire to have at a perticular point in time.
substitutes and complements
Amman Reply
Substitute are goods that can replace another good but complements goods that can be combined together
account for persistent increase in lnflation
niwahereza Reply
what is opportunity cost
Adebowale Reply
opportunity cost reffered to as alternative foregone when choice is made
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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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