LabVIEW Interview Questions and Answers
by Sachin, on Jul 4, 2022 8:40:53 PM
Q1. How Do I Validate A LabVIEW Application?
To verify and for cetifying a LabView application, you need to demonstrate similar development practices like with any of the programming languages. By this, you can make sure that any kind of risk associated with the application has been adequately mitigated.
Q2. What Is The Difference Between Local Variable And Global Variable In LabVIEW?
Local Variables: The Local Variable item is located on the Structures palette on the Block Diagram(BD). When you place a Local variable in BD panel, it will look like a question mark symbol. After this just right click on the local variable & choose 'Select Item' & select which Indicator/Control you would like to connect it to. The other way to create the local variable is to right-click on a Indicator/Control either in Front Panel or in BD and select 'Create Local Variable'.
Global Variables: Use global variables to access and pass data among several VIs. When you place a global variable on the Block Diagram, it looks like a question mark with globe symbol. Once you create global variable in any LabVIEW VI, LabVIEW engine automatically creates 'global variable vi' in the following directory. Pls. note that only front panel of the global variable exists.
Q3. Is LabVIEW A Compiled Programming Language?
Yes. LabVIEW has a sophisticated compiler that is always running as you develop your application. When the compiler finds a syntactical error the run arrow is broken to indicate that the application cannot run. Continuous investment in the LabVIEW compiler has enabled optimized application performance and, amongst other things, the ability to take full advantage of multicore technologies.
Q4. What are two panels used in LabVIEW programming?
There are two types of panel viz. front panel and block diagram. Block diagram is the panel where all the programming is carried out. Front panel is the one visible as user programmable interface i.e. GUI interface.
Q5. Features of LabVIEW?
- User-friendly UI: It has a user-friendly drag and drop kind of interactive User Interface.
- Built-in Functions: It supports thousands of inbuilt functions that range from analysis and I/O etc. These belong to the function palette.
- Scalable: As LabVIEW has a modular design making it easy to scale and modulazier programs.
- Professional Development Tools: It has a plethora of tools that help integrate and debug large applications.
- Open environment: It has tools needed for many open environment developments.
- Object–oriented design: It supports object-oriented programming structures enabling encapsulation and inheritance to create modular and extensible code.
- Compiled language: Being a compiled language it is faster.
Q6. What are the benefits of LabVIEW?
- Ease of first acquisition for DAQ.
- The NI ecosystem.
- Parallel processing.
- Lowered barrier to entry for FPGA-based programming.
- Measurement data visualization.
- Ease of interfacing with instrumentation.
- Ease of interfacing over different communication links.
Q7. How do you define a state machine?
A state machine reads a set of inputs and changes to a different state based on those inputs. A state is a description of the status of a system waiting to execute a transition. A transition is a set of actions to execute when a condition is fulfilled or an event received.
In LabVIEW, a shift register is used to store data during looping (while and for loops). The shift register lets you access data and return the value from the previous iteration. It's like a local variable inside a loop in a text-based language. You can use a shift register within a loop to: Store/update data.
Q9. What Are The Building Blocks Of LabVIEW Language?
- Front Panel.
- Controls Palette.
- Controls and Indicators.
- Block Diagram.
- Controls, Indicators, and Constants.
- Block Diagram Nodes.
- Functions Palette.
Q10. What are the two main visual interfaces of LabVIEW?
- VI Front Panel: The LabVIEW front panel is what the user of the completed application will see.
- VI block diagram: The LabVIEW VI block diagram is where the functionality of the VI is programmed in G.
Q11. What is LabVIEW SignalExpress?
LabVIEW SignalExpress is an interactive measurement program you can use to quickly acquire, analyze, and present data from hundreds of data acquisition devices and instruments, with no programming required. Use LabVIEW SignalExpress to create projects that acquire, analyze, create, generate, and display signals.