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Practice debugging techniques.

Complete the following steps to load a broken VI and correct the error. Use single-stepping and execution highlighting to stepthrough the VI.

Front panel

  • Select File>>Open and navigate to C:\Exercises\LabVIEW Basics I to open the Debug Exercise (Main) VI.The front panel shown in appears.
    Notice the Run button on the toolbar appears broken, shown in , indicating that the VI is broken and cannot run.

Block diagram

  • Select Window>>Show Block Diagram to display the block diagram shown in .
    The Random Number (0-1) function, located on the Functions>>Arithmetic&Comparison>>Express Numeric palette, produces a random number between 0 and 1 .The Multiply function, located on the Functions>>Arithmetic&Comparison>>Express Numeric palette, multiplies the random number by 10.0 .The numeric constant , located on the Functions>>Arithmetic&Comparison>>Express Numeric palette, is the number to multiply by the random number.The Debug Exercise (Sub) VI, located in the C:\Exercises\ LabVIEW Basics I directory, adds 100.0 and calculates the square root of the value.
  • Find and fix each error.
    • Click the broken Run button to display the Error list window, which lists all the errors.
    • Select an error description in the Error list window. The Details section describes the error and in some cases recommends how tocorrect the error.
    • Click the Help button to display a topic in the LabVIEW Help that describes the error in detail and includes step-by-step instructions forcorrecting the error.
    • Click the Show Error button or double-click the error description to highlight the area on the blockdiagram that contains the error.
    • Use the Error list window to fix each error.
  • Select File>>Save to save the VI.
  • Display the front panel by clicking it or by selecting Window>>Show Front Panel .

Run the vi

  • Click the Run button to run the VI several times.
  • Select Window>>Show Block Diagram to display the block diagram.
  • Animate the flow of data through the block diagram.
    • Click the Highlight Execution button, shown in , on the toolbar to enable execution highlighting.
    • Click the Step Into button, shown in , to start single-stepping. Execution highlighting shows the movement of data on the blockdiagram from one node to another using bubbles that move along the wires. Nodes blink to indicate they are readyto execute.
    • Click the Step Over button, shown in , after each node to step through the entire block diagram. Each time you click the Step Over button, the current node executes and pauses at the next node.Data appear on the front panel as you step through the VI. The VI generates a random number and multiplies itby 10.0 . The subVI adds 100.0 and takes the square root of the result.
    • When a blinking border surrounds the entire block diagram, click the Step Out button, shown in , to stop single-stepping through the Debug Exercise (Main) VI.
  • Single-step through the VI and its subVI.
    • Click the Step Into button to start single-stepping.
    • When the Debug Exercise (Sub) VI blinks, click the Step Into button. Notice the run button on the subVI.
    • Display the Debug Exercise (Main) VI block diagram by clicking it. A green glyph, shown in , appears on the subVI icon on the Debug Exercise (Main) VI block diagram, indicating that the subVI is running.
    • Display the Debug Exercise (Sub) VI block diagram by clicking it.
    • Click the Step Out button twice to finish single-stepping through the subVI block diagram. The Debug Exercise (Main) VI block diagram is active.
    • Click the Step Out button to stop single-stepping.
  • Use a probe to check intermediate values on a wire as a VI runs.
    • Use the Probe tool, shown , to click any wire. A window similar to appears.
      LabVIEW numbers the Probe window automatically and displays the same number in a glyph onthe wire you clicked.
    • Single-step through the VI again. The Probe window displays data passed along the wire.
  • Place breakpoints on the block diagram to pause execution at that location.
    • Use the Breakpoint tool, shown in , to click nodes or wires. Place a breakpoint on the block diagram to pause execution afterall nodes on the block diagram execute.
    • Click the Run button to run the VI. When you reach a breakpoint during execution, the VI pausesand the Pause button on the toolbar appears red.
    • Click the Continue button, shown , to continue running to the next breakpoint or until the VI finishes running.
    • Use the Breakpoint tool to click the breakpoints you set and remove them.
  • Click the Highlight Execution button to disable execution highlighting.
  • Select File>>Close to close the VI and all open windows.

Questions & Answers

how environment affect demand and supply of commodity ?
Amos Reply
Wht at the criteria for market ?
what is difference between monitory policy and fiscal policy?
Malik Reply
monetary policy is a policy thrust by National Govt(CBN) to influence government spending, purchase &taxes
necessity of economics
Pamela Reply
I will say want,choice,opportunity cost,scarcity,scale of preference
what is monopoly market.How price output are determined under monopoly market
b) Monopoly market is an impecfect market where s single firm having the innovation to produce a particular commodity.Prices are determined through output since there are no other competitive.
Monopoly market:firm has market power & does not respond to market price
Explain the process of price determination under perfect competition market with suitable diagram
bisham Reply
Price determination under perfect competition via this process :firms have no market power to influence price rather firms respond to market price.
price is different from demand- demand is amount of commodity
Effah Reply
demand is amount /quantity of commodity a potential buyer is willing to buy at a given price at market
demand is a desire of customer on commodity with the ability to pay it and willing to buy it at given price of commodity
demand is price of what
Faith Reply
show that shortrun average cost
Baby Reply
what is economics
Mbah Reply
what is money
what is money
Difine macro economics
money is a medium of exchange between goods and services,maybe inform of currency.
Economics is study of how human beings strive to satisfy numerous wants using limited available resources.
how do you find the maximum number of workers the firms should employ order to produce where there are increasing returns
what are implications of computing national income?.
what is the formulae for calculating national income
it calculated by value added method
classify the production units like agriculture, banking, transport etc
money is anything that is generally acceptetable for human
Estimate the net value added(NVA) at fixed cost by each industrial structure
definition of unemployment
Adam Reply
what are the causes of unemployment?
Mbubi Reply
The main causes of unemployment are listed below. 1. Frictional unemployment 2. Cyclical unemployment 3. Structural unemployment
We can also categorize the causes on a broader sense as: 1. Political and 2. Social cause As unemployeement root causes are embaded in this two.
would opportunity cost exist if there was no scarcity?
yes just because the opportunity cost arose when there is Alternative to choose among the alternatives.
I am thinking that, if our resources were unlimited, then there wouldn't be any need to forgo some wants. Hence the inexistence if opportunity cost
politics has done what?
consider time assani
I'm Emmanuel,...I taught the main cause is the change in gov't.
...Lack of capital to set up a firm respectively
I would like to bring in Educational levels can also be the cause the cause of the problem respectively
lack of skills among the new generation is the serious issue.
Where I come from , I don't see why education or personal aspects seem to do with unimployment, technically the motivation and eigerness in all works of live is there , dispite the cultural influence and physical bearriors;the thing we lacking is Government Support and open market ethics.
sorry about that-(repation). We have a over powering ethical political system that's displacing the marketing asspects of economy and causing large scale unemployment right across the board...
can someone Explain Expansionary Monetary Policy and Contractionary Monetary Policy Using one of the instrument of Monetary Policy? Please am kinda lost here?. ta
Emmanuel Reply
using a graph show the case of substitute and compliment goods
Ade Reply
can anyone give me a simple explanation to Five Sector Macroeconomics?
Can someone please define what economics is
jason Reply
economics simply is a social science subject that study human behavior.
economics is a social science which studies human behaviour as a relationship between ends and scarce means that has alternative uses
Can someone please tell me how to calculate GDP
emmanual kapal to calculate GDP (Gross Domestic Product) has three method in calculating it (1)income approach (2) expenditure approach (3) value added method
thanks Alae
u are welcome
in basic terms economics is revered to as battery system, it date back to when Men sees the need to exchange sapless goods and produce to gain , either wealth , basic necessities or to establish trading ties for personal benefit or social asspects in terms of coexistence and continuity, future .
what is the law of demand
Berlinda Reply
keep other thing constant, when the price increases demand decrease when the price decreases demand increases of the commodity.
all things being equal,quantity demanded decrease as price increase and increase as price decrease
there's practial joke to it ..." the higher the demand ; scarcity, increase in production and drop in quality"... quite the controversy - for example China vs Europe, United States and we are all boxed up in between somewhere...
Other thing remain constant the low price of commodity the high quantity of commodity and vice versa is true
Explain Effective demand
Anita Reply
What is effective demand
like Modi is in demand...best example of effective demand
Don't get you
Anita you mean you don't get me or who?
level of demand that represents a real intention to purchase by people with the means to pay
Difference between extinct and extici spicies
Amanpreet Reply
While the American heart association suggests that meditation might be used in conjunction with more traditional treatments as a way to manage hypertension
Beverly Reply
in a comparison of the stages of meiosis to the stage of mitosis, which stages are unique to meiosis and which stages have the same event in botg meiosis and mitosis
Leah Reply
Researchers demonstrated that the hippocampus functions in memory processing by creating lesions in the hippocampi of rats, which resulted in ________.
Mapo Reply
The formulation of new memories is sometimes called ________, and the process of bringing up old memories is called ________.
Mapo 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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