Lab view coder wants challange

Experienced Lab view programmer looking for new challenges in the north of Boston, MA area.  If you are in need of a programmer please contact me.

hey!!
Am a university student currently working on a project of 16 qam modem using labview 8.2...dsp kit am using is 6713....Will you be able to help me in this regard....as you are an experienced programmer you must have got some help matrerial for me...
thanx alot
wajahat Hassan

Similar Messages

  • Why is the Tick Count function slow when used with a .dll but fine with normal lab view code?

    when using the Tick Count millisecond timer with a .dll I've written in C, I'm getting some odd timing issues.
    When I code the function I want (I'll explain it below in case it helps) in LV and run it as a subVI, feeding it the Tick count as an argument, the function runs quickly, but not quite as quickly as I would like. When I feed this same subVI just an integer constant rather than the Tick Count, it takes about the same amount of time, maybe a tiny bit more on average.
    When I bring in my function from a .dll, however, I start to run into problems. When I feed my function an integer constant, it is much faster than my subVI written in LV. When I feel my .dll the Tick Count, however, it slows down tremendously. I'm including a table with the times below:
                 |  Clock   |   Constant   |
    SubVi:   | 450ms  |  465ms       |
    .dll         | 4900ms|  75ms         |
    This is running the function 100,000 times. The function basically shifts the contents of a 2-dimensional array one place. For this function, it probably won't be a huge deal for me, but I plan on moving some of my other code out of LV and into C to speed it up, so I'd really like to figure this out.
    Thanks,
    Aaron

    Hi Aaron,
    Thanks for posting the code -- that made things a lot clearer for me. I believe I know what's going on here, and the good news is that it's easy to correct! (You shouldn't apologize for this though, as even an experienced LabVIEW programmer could run into a similar situation.) Let me explain...
    When you set your Call Library Function Node to run in the UI Thread you're telling LabVIEW that your DLL is not Thread-safe -- this means that under no circumstances should the DLL be called from more than one place at a time. Since LabVIEW itself is inherently multithreaded the way to work with a "thread-unsafe" DLL is to run it in a dedicated thread -- in this case, the UI thread. This safety comes at a price, however, as your program will have to constantly thread-swap to call the DLL and then execute block diagram code. This thread-swapping can come with a performance hit, which is what you're seeing in your application.
    The reason your "MSTick fine behavior.vi" works is that it isn't swapping threads with each iteration of the for loop -- same with the "MSTick bad behavior.vi" without the Tick Count function. When you introduce the Tick Count Function in the for loop, LabVIEW now has to swap threads every single iteration -- this is where your performance issues originate. In fact, you could reproduce the same behavior with any function (not just TIck Count) or any DLL. You could even make your "MSTick fine behavior.vi" misbehave by placing a control property node in the for loop. (Property nodes are also executed in the UI thread).
    So what's the solution? If your DLL is thread-safe, configure the call library function node to be "reentrant." You should see a pretty drastic reduction in the amount of time it takes your code to execute. In general, you can tell if your DLL is thread-safe when:
    The code is thread safe when it does not store any global data, such as global variables, files on disk, and so on.
    The code is thread safe when it does not access any hardware. In other words, the code does not contain register-level programming.
    The code is thread safe when it does not make any calls to any functions, shared libraries, or drivers that are not thread safe.
    The code is thread safe when it uses semaphores or mutexes to protect access to global resources.
    The code is thread safe when it is called by only one non-reentrant VI.
    There are also a few documents on the website that you may want to take a look at, if you want some more details on this:
    Configuring the Call Library Function Node
    An Overview of Accessing DLLs or Shared Libraries from LabVIEW
    VI Execution Speed
    I hope this helps clear-up some confusion -- best of luck with your application!
    Charlie S.
    Visit ni.com/gettingstarted for step-by-step help in setting up your system

  • I want to control the front panel of a lab View program with C code??

    I want to be able to run lab View via Corba. So I need some way to control my lab Vew programs with C code. I really hope this is enough INFO.

    Hi Mikey,
    As mentioned by the guru more details would help us help you.
    Do you just want to start the LV app from Corba?
    Do you need to specify start-up value for the LV app?
    Do you want want Corba to Fiddle with buttons and controls on the FP of the LV app?
    Please outline your "dream" and we will let you know what is possible.
    Ben
    Ben Rayner
    I am currently active on.. MainStream Preppers
    Rayner's Ridge is under construction

  • I want to get and set windows system time through lab view

    Hi
    I want to get and set windows system time with the help of lab view 8.5.
    please help me out.
    ekanth

    You can use the call library function node. Once you drop it on your block diagram double click it and you will be able to select the dllyou want to use. Choose kernel32.dll and you will see methods listed called getsystemtime and setsystemtime. Use those
    CLA, LabVIEW Versions 2010-2013

  • In lab view from RS-232 serial port we want to read and diplay that value

    Hello,
             In lab VIEW 8.0,we want to read some data values via
    RS-232, how to read those values, we tried with visa read for read, but that is not displaying the buffer values.

    Hi,
    There is a nice example that come with labview for writing and reading to an RS232 port, I suggest you take a look at this.
    Regards
    Ray Farmer
    Regards
    Ray Farmer

  • How to control a NI USB 6210 from a Lab View program?

    Hi,
    I started today with Lab View with some earlier experience long ago.
    While it took me only about half an hour to get my first program running (great), installation time nor included (of course), I meanwhile read documents for some hours and cannot find out how to control measurement hardware in Lab View.
    I want to use a USB 6210 to set a 1-bit digital port. But at the moment there is no USB6210 available so I wanted to write (or do you say draw ?) the program without it and if possible simulate the hardware.
    I drew DAQ Assistant into my block diagram and selected digital line output but get "No supported devices found". I don't know if the appropriate driver was installed during Lab View installation.
    Also I don't understand the mechanism between DAQmx, tasks and the real hardware. Now I have a "Digital Bool 1Line 1Point" Control in my block diagram. How do signals get from program flow to hardware pin? How can I create a simulation for not connected hardware?
    Any help is greatly welcome
    Thanks a lot
    Martin

    Okay here is some more tutorials if you get some free time, specifically the hardware stuff will be relavent.
    NI Learning Center
    NI Getting Started
    -Hardware Basics
    -LabVEW Basics
    -DAQ Application Tutorials
    3 Hour LabVIEW Introduction
    6 Hour LabVIEW Introduction
    Self Paced training for students
    Self Paced training beginner to advanced, SSP Required
    LabVIEW Wiki on Training
    Launch MAX, it was known as Measurement and Automation Explorer, there should be a shortcut in your start menu / desktop.  Under devices and interfaces you can find your hardware and open test panels to control it.  This is the first place to ensure your hardware is working.  If the device isn't seen you'll need to install the drivers and DAQmx software.  If it is there, great.
    Now launch LabVIEW.  The easiest way to control hardware is using the DAQ Assistant.  It has many limitations and isn't recommended for large applications.  But for something quick and dirty it works fine.  You'll find it under the Measurement I/O >> NI DAQmx palette on the block diagram.  If it isn't there you may need to reinstall the DAQmx drivers.  This can happen if you installed DAQmx before LabVIEW.
    Also you'll find under Help >> Find Examples on the toolbar, many examples on controlling hardware.  Feel free to post some code if  you are having problems.
    Unofficial Forum Rules and Guidelines - Hooovahh - LabVIEW Overlord
    If 10 out of 10 experts in any field say something is bad, you should probably take their opinion seriously.

  • How to configure a shell and tube heat exchanger with Lab VIew to get data

    HiI
    In our undergraduate chemical engineering labboratory we want to configure our shell and tube heat exchanger  with a DAq and Lab VIEW to get information about the temperaure (of the cold fluid stream being heated), the pressure (of the steam on the shell side of the heat exchanger) and the flowrate (of the water being heated).
    Can anyone suggest thermocouples, pressure transducers and flowmeters to fit between the heat exchanger and the DAq?
    P.S. the heat exchanger is already fitted with thermometers, a pressure gauge and a rotameter but we don't know how to connect these hardware to the DAq
    Solved!
    Go to Solution.

    It sounds like you have enough information to pick out appropriate sensors, you just need to do the research. I would start looking through the Omega catalog, or give them a call - they're usually helpful. I can't take the time to spec out parts for you - that would be a lot of time spent on someone else's project. Most pressure sensors put out either a 4-20mA or 0-5V signal, either of which you can read through an analog input on a DAQ; measuring a 4-20mA signal requires a resistor to convert to voltage. Most of the NI DAQ boards can read a thermocouple on an analog input, but make sure that your hardware does support reading thermocouples. For accurate readings, use a device that has built-in cold junction compensation - for example, the SCB-68 connector block - and for the most accurate readings, get a board specifically designed for temperature measurement.
    For the flow measurement, a standard, simple solution is an orifice plate. You put a differential pressure transducer across it, look up the appropriate equations, and use them to calculate the flow rate given the density of the fluid (which you'll be able to calculate from the pressure and temperature, since steam tables are widely available). There are other differential pressure devices available as well - at a previous job we used a V-Cone from McCrometer. If you call them they'll spec one for you - but get an approximate cost first to make sure it's within your budget.

  • How to get lab view to display my plot in DB

    hi guys
    i desigED n an operational amplifier to determine the gain product band width using a 741 chip and the gain of the circuit is 1000, meaning that the gain bandwidth PRODUCT  will occur at a frequency of 100hz. but i have a problem, when i start the frequency sweep from the function generator from 10 hz to 100Khz which  IS the final frequency value i have set for the program. when the lab view program stops and i export the data to excel sheet i will be getting the DB axis value in a SMALL VALUES AND IN DIFFERENT  UNITES  WHEN I PLOT THE GRAPH USING EXCEL,  while the frequency is in log10.
           pls can any one tell me how to solve this problem to start getting the right cut off  frquency on the graph. find aattched my vi and the excel data from the vi that is in a different unit not in DB
    Attachments:
    GAIN BAND WIDTH PRODUCT.vi ‏116 KB
    FREQUENCY VALUE .xls ‏26 KB

    Ahhh.....
    emeho wrote:
    thanks Jeff Bohrer  for your reply, what i mean is the y-axs of the plot is in DB aleady, but when i export the data to excel i will be seeing the gain in 0.8, 0.7,0.4 which is not normal,  which will not give me the -3db point of the gainband width product of the circuit
    What you want to do is plot the Log(10) of the frequency on a linear axis!!!!!!!  The export - exports the values not the axis scale.  exporting a log(10) of the Y axis will export the log of the axis- (of couse, you could change the graph axis scale in Excel too...... but)
    Jeff

  • Versions of lab view

    Hi:
    Just a few days ago i put this message:
    Hi:
    Im trying, to find a way to search, a file stored in different subfolders of a main folder, and copy, i mean i have a VI which makes a folder everyday (the name istoday date, or yesterday date), and inside that folder is a serial1.txt log file, but yesterday (for axample) the same log file (serial1.txt) was generated, how can i search in lab view all of those serial1.txt files?? By putting just in the search field, the main folder name??? 
    And I want to copy each of these serial1.txt, to different paths???
    So in this days, i ve working and the file is ready, but this archive just search like this: main directory /2nd directory/ 3rd directory/Files.... I mean if the files is deeper in more subdirectorys, does not work well works for me.   
    Im working in lab view 8.5 but, when i tried to put the .exe file in the computers where i have to look for my files, sorprise!!! the computers have the version 7 express or somethig like that so i cant use my file. IT Is possible change the version of my file to version 7?????  
    Solved!
    Go to Solution.
    Attachments:
    search_engine_lol.vi ‏117 KB

    I don't know if you are still asking the same question in this thread or not. If you are, don't start a new thread. 
    As far as the exe, all you have to do is install the 8.5 run-time engine on the other PCs. If you had created an installer (something you should always do), the run-time would have been included.

  • Hide/unhide radio buttons works in lab view, not in executable

    Hello,
    I simplified a program I am using. When I run in lab view the radio buttons are visible or not (as programmed). But when I create an executable, this function is not working any more?
    Do I need to make changes in the build settings?
    best regards,
    Rens van Geffen
    I attached the maintest.vi (lab view program) and the executable as well in a zipped folder.
    Attachments:
    My Application2.zip ‏742 KB

    I think it is a bug and reported it in the monthly bug thread.
    RvG wrote:
    Yes i know it is a dirty vi. But I only made it because I had a problem in a complicated vi, with lots of sub vi's etc. in that vi I have all wait functions etc.
    I did not care about any wait function. I was just objecting about the overuse of value property nodes and that exceedingly complicated inner while loop construct that really does not do that much.
    For example, your upper case structure contains writing to two value properties that exist in all cases, while the actual terminal just sits there outside the loop. The cases only need to contain what's different. Shared code elements belong outside the case! Instead of writing to value properties (which is synchronous and resource intensive), you can just write to the indicator terminal instead. Right?
    In parallel to writing to the "group", you also read from another value property instance of the same. Since this happens in parallel to the case structure, you will read a stale value, and not what has been generated by the case structure during the same interation.
    My code modification shows some of the simplications that can be done. Also note that data dependencies enforce the proper execution order.
    Writing to the visible properties only needs to be done when the situation changes and not with every iteration of the loop. Once written, these proerties stay until changed to something else.
    In summarry, these are just some recommendations. They will not fix the LabVIEW bug you exposed.
    LabVIEW Champion . Do more with less code and in less time .

  • Can I use a CEC - Camera with Lab View 6.0?? what do i habe to notice?

    I want to treat real time - pictures with Lab - view 6.0. Is that possible?

    Hello,
    www.ni.com/camera is a camera advisor designed to give you detailed information on the supported types and brands/models of cameras.
    Hope this helps!
    Regards,
    Yusuf C.
    Applications Engineering
    National Instruments

  • Lab View - Ignition Timing Graph Plot

    Need expeienced Lab View programmer for ignition system timing advance graph. All hardware and interfaces intact. Work possibly may be completed remotely if desired. Project location: Fresno CA.
    For more information email JTMDropbox@gmail .com

    Ahhh.....
    emeho wrote:
    thanks Jeff Bohrer  for your reply, what i mean is the y-axs of the plot is in DB aleady, but when i export the data to excel i will be seeing the gain in 0.8, 0.7,0.4 which is not normal,  which will not give me the -3db point of the gainband width product of the circuit
    What you want to do is plot the Log(10) of the frequency on a linear axis!!!!!!!  The export - exports the values not the axis scale.  exporting a log(10) of the Y axis will export the log of the axis- (of couse, you could change the graph axis scale in Excel too...... but)
    Jeff

  • Lab view programming to control the printer

    Hi,
    As part of my senior design, I am working on LAb view programming. Though I know some basics of lab view, I don't know how to apporach it in the right way. Our device is a dispenser (ink jet printer) which has to dispense user defined amount in user defined location. lab view program has to be interfaced with the printer to do so. I know some basics of lab view and currently I don't know where I am heading to. I have also read the one discussion forum on Lab view FPGA to control an inkjet printer which  discussed about FPGA module.  
    Thanks,
    Sundeep

    No, I'm saying that depending on the level that you are interfacing would determine whether the FPGA would be a good answer. If you are interfacing to an existing inkjet printer, where you may need to just provide it with the appropriate values through an existing interface, then FPGA would probably not be the answer. If you are connecting at a lower hardware level where you need to directly control the print head, positioning "stuff" etc., then it might. But as I said, and you have reiterated, it is expensive. FPGA allows you to through "software" define a hardware logic. It is particularly good for those things that need very critical timings between signals as it basically programs a digital logic card, therefore the timings are no longer software/operating system dependent, they are in hardware, with outputs and internal signal changes dependent on internal, hardware, clock transistions. You mention that the printer is an epson inkjet. Are you talking a standard, plug it into a computer, epson printer? Are you expecting to "hack" its hardware to get control of those functions you mentioned, like user controlled ink quantity, etc.? You will have to tell us what you have in a little more detail, and what you expect to have to do. Interface to a printer can be hooking up a parallel, or usb connection and sending the codes to print (which in LabVIEW can be its own hurdle!) to the extreme of cutting into existing hardware to introduce "internal" control signals that substitute for the original. The first step to trying to solve your technical problem is being able to describe what it is that you are trying to do, in as much detail as possible.
    Putnam
    Certified LabVIEW Developer
    Senior Test Engineer
    Currently using LV 6.1-LabVIEW 2012, RT8.5
    LabVIEW Champion

  • Lab View is not detecting two com ports of system

    Hi,
       In my PC, three com ports are there COM1, COM4 and COM6. But when we create new visa resource name, lab view is detecting only COM1 port. I want to know is there any way to correct this.
    Regards
    Shivakumar Singh

    Hi,
    First of all check if the ports are visible in the NI MAX. If not, you can try to Create New Port by going into Measuremenmt & Automation Explorer. Assign the Port values accordingly. This can be done by right clicking on the Ports (Serial & Parallel) section of the Devices and Interfaces tree.
    Regards,
    Deepu.

  • In search of Projects based on Lab view.

    Hi,
        Iam Chaitanya, pursuing M.tech.. Iam using Lab VIEW,it is a good platform to work in realistic so I interested to do Lab VIEW projects. Can you please suggest projects based on Real-time applications or electronics.

    Hi Chaitanya,
                         In real time application you can go for the projects like dataloggers which having communications. Here all the operations on datalogger can be done using labview. You can plot the graphs, show the RTC, download and process flash & eeprom memory and so on.
    Or you can go for TCP like projects where some equipments are sending data using TCP and you are reading that data using TCP tools in labview and write to database,excel and plot it later.
    Its all depends on you what you want.
    Thanks
    Kudos are always welcome if you got solution to some extent.
    I need my difficulties because they are necessary to enjoy my success.
    --Ranjeet

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