Re: SubVI with loop-back
Thanks for your answer! I thought of using the shift registers in combination with a while loop. But I could not get this to help me realising a SubVI with a back-loop. The thing is, that I want to realise a function with a back-loop within a subVI while the back-loop is positioned outside of the subVI. This is to e.g. read a bundled output of the subVI in the mainVI, unbundel it it in the mainVI, choose one of the list-items in the mainVI, give this as back-loop input to the subVI. I could not realize this by using a while loop with sift registers. Thanks for any further help! Andreas Hegenbart
Best books to get up to speed with LabView 7?
I am presently looking for advice as to the best book(s) to get up to speed with LabView 7 (Best beginner's book, best intermediate book, best advanced book). Any books to advoid? While I prefer hardcopy, I would be open to the best online resources as well. Art
Re: RS232 vs RS485
Yes but thanks I have solved. The problem was the delay of external module. Bye.
labview and Eagle pc104 card install Problem
Hello I have problems to install a PC104 eagle card in labview6.0 Afer I Install the the eagle card on the computer. (It works fine, and was installed proper, that tells me also the systemconfig) and than I have install the LabVIEW Interface Driver For EDRE I cannot find it in labview or labview can not find it ? I dont know how I can install it in Labview. Should i install the card in Labview or should labview see the card automatically ? Can give me someone some hints or a desciption what I have to install first ... I make it like this: 1. Installing Eaglecard in the system 2. Installing Labview 6.0 3. installing LabVIEW Interface Driver For EDRE - now labview do not find the card and I find no option to activate the card thanks Michael Haas
Re: simultaneous analog output 1k sine wave and data acquisition
I have sucessfully solve the problem when I observed the increase of scan backlog number. Simply increase the buffer size of AI/AO and you can make the 1kHz sine wave output and data acquired properly. On Tue, 3 Feb 2004 09:03:07 -0600 (CST), jujian [EMAIL PROTECTED] wrote: Although many topics of simultaneous analog output and input can be found in NI Developer Zone, I have not found a case similar to my project. I'm trying to generate a 1kHz sine wave by using the analog output of NI DAQPad-6070E, and acquire one channel input signal simultaneously. I found most of the examples can not work properly above 100Hz. Any suggestions are welcome. Thank you. Jian
Q: Compare LabView for Linux Windows
Hello, I've a question regarding LabView. We are looking for a new plattform for developing test systems and think LabView fits our requirements. Now LabView is available for Linux as well as for Windows. Know the question is if both are compareable or if one system (Linux or Windows) has got some more features? Are there any advantages of LabView for Linux compared with LabView for Windows? Thanks for all comments. CU, Gerald
2 channels data acquisition sychronized with analog output
My labview program can generate 1kHz sine wave and acquire one channel analog input simultaneouly. Now I modified it for acquiring two channel voltage signal by adding channels in analog config vi. The program sometimes can get the right analog input and sometimes can't. Can someone suggest solutions for this? Thank you in advance. Jian
ni-488.2 language support
Hello, I am evaluating LV 7 for the possibility of using related language support. We have the option of developing in either Microsoft Visual C++ or Borland C++Builder. Would the Microsoft C and Borland C, respectively, apply in that case? I am assuming that we would link with either the gpib-32.obj or BorlandC_gpib-32.obj, respectively? Commands and responses would then be sent and received using whatever native GPIB protocol is relevant for the device? Any specific things we should be aware of where multiple GPIB buses and/or device addresses are concerned? Regards, Michael Powell
lv gpib32.dll hardware support
Hello, Does NI gpib32.dll support other vendor hardware, such as Agilent PCI GPIB cards? Or do we need to have NI cards? Regards, Michael Powell
problem about datasocket and activex
when I embeded an datasocket activex contorl(made with VB6,labview UI included,pacakged to .cab file) in a web page, it can not be appeared in client computers. I have adjusted the security in IE,but fruitlessly. If the activeX contorl didn't include the activex controls NI provided, it can be appeared in clients. what should I do?
Re: Filtering out and sending data to the correct graph depending on data identifier
The nano satellite will talk on RS-232 9600 baud and since I'm programming the PIC MCU I can make up my own protocol. I'm thinking something like: Groundstation sends this: ?Temperature1 And the satellite then replies: !Temperature1[Data]EndofData I will have 10 different probes in the satellite, monitoring currents, voltages and temperatures and I need some help and tips on how to filter the incomming string and split it up so that I can route the approrpriate data to the appropriate frontpanel? or graph. If you let the satelite send a ASCII telegram of comma separated floating point numbers (one float for each measured parameter) for example every second. You will have to predefine the number of parameters and in wich order they are sendt. After the last parameter you can add a checksum to varify the received telegram. End the telegram with a carriage return and linefeed. Satelite ID,CH1,Ch2,...,CHn,ChkSumCRLF In your serial read vi, you can detect the CRLF and convert the telegram into an array of floats. This is a common way of sending data from dataloggers. If you don't want to use a predefined update rate, you can poll the satelite and use the same sort of telegram as the answer. This way you don't need to worry about the identification of the measured parameters. Erik
Re: Thermocouple problem with 6024E DAQ
Are you reading from the virtual channel in LabVIEW? You didn't mention this and so I'm wandering whether you are reading from the virtual channel in LabVIEW or if you are reading the voltage in LabVIEW and converting that to a temperature within LabVIEW. If you're not reading from the virtual channel in LabVIEW, then I would suggest to try. You can simply open up a generic continuous analog input example in LabVIEW and rather than reading from a channel number in LabVIEW, read from the virtual channel name. If you're reading from the virtual channel already in LabVIEW, then this does seem a little odd. What sampling rate are you using in LabVIEW? Or are you just reading one point at a time? Let me know. Regards, Todd D. NI Applications Engineer Problem solved Thanks. Yes I was reading from the virtual channel. If I had paid better attention I would have noticed that the Test panel in the virtual channel setup says average value. The solution is to take an average. Here is the Fix. Put the Sample Channel VI in a forloop. Out side the loop use add array then connect to Divide symbol. Create a constant in the for loop N of 200. The divide constant must match this number. The higer the number the more noise it removes. Basicly what you have here is a software signal conditioner to a point. It works very well. If you want to see the effects build a VI using random number Zero to one. Wire a Control knob to the divide and forloop N. Note that the zero to 1 stays with in a range of .4 to .6. Basicly it takes an average.
Re: selecting multiple files
ramssted b wrote: I modified multi-selection dialogbox.vi and now i have an array of strings that has paths of the selected files. How can i read these files one at time and make some calculation out of them and after that create graph from the answers. Some kind of loop perhaps? You could use a for-loop with the auto-index feature. This gives you one path after the other from the array insisde the loop. Alternatively you could use the Index Array Function to get single elements (paths) out of the array. Hope it helps Marco
Multicolors in string?
I can make sections of text in a string indicator different colors manually but I can't figure out a way to do it programmatically. The goal here is to highlight two sections of a long text string by making them different colors while leaving the rest black. Any ideas?? Tom
Panel Object xy coordinates and Multiple window list in task bar
Two questions... I recently had to rearange panel objects to programatically display them. They were not at the origin, and had to futz them into position. Is the first object placed, placed at the origin? Could the guys at NI provide an xy indicator? And second, I built my application, but in the task bar there is a listing for the app, then another listing for the window name. How can I clean this up? XP LV 6.1 Cheers
Re: Multicolors in string?
Martin, Thanks, that did it. I was using Property node - text - text colors - text color and the whole string was turning color (even after selection). Thanks again. Tom On Sun, 08 Feb 2004 00:53:42 GMT, Martin Riddle [EMAIL PROTECTED] wrote: You must select the text first. Property node - text - Select - Start Property node - text - Select - End Then... Property node - text - Font - color It doesn't look like you can change the background for individual characters though. Hope that helps. Cheers Tom Whitaker [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] I can make sections of text in a string indicator different colors manually but I can't figure out a way to do it programmatically. The goal here is to highlight two sections of a long text string by making them different colors while leaving the rest black. Any ideas?? Tom
Re: New to Lab view! Need some Help.
I am rather new myself but have suggestion. Can he talk to M.S. Access files via ActiveX. I have not worked directly with LabView database files but have experience posting and drawing data from Excel files and Access. This seems to be a more viable option. Rebuttal? Seth jcrooke [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] I can help you get started with your project, but first, please, provide more information. Do you have to keep your database in MS Notepad files, or can you create datalog files in LabvIEW to serve as your databases. Things are much easier for you if you can work directly with LabvIEW data structures, which are saved into datalog files with full retention of the data types. Reading, scanning, sorting, and all of those sorts of activities are much easier when working directly with LabVIEW data structures. You could then create a special routine that parses your data into any structure you wish for the benefit of other users. I am not very familiar with common database structures. I build databases as I have mentioned above, using LabVIEW datalog files. It may not be as efficient as a true database structure, but unless you are talking about large amounts of data distributed over various servers, I would think that the datalog file would suffice. Please, define the relational characteristics of these databases. Does database1(message data) just contain lists of messages within a matrix of lookup parameters? What is node data? Is this also just a list of identifiers or strings? I beg your pardon, but I need you to describe your task in more generic programming terms, a lower level than the database structure. Once we get beyond this initial communication gap, I can help you. You said, in my application I need to have a dialog box with the VEHICLE.VCF extention. I need a more careful explanation of this. Do you mean that your dialog box must produce a file named VEHICLE.VCF? Do you mean that your dialog box is a file dialog that filters candidate files by the .VCF extension? You said, database1(message data) this needs to have few massages chosen from the main database1 and should be able to save them in background. It sounds like you want the user to be presented with a list of messages, which you have drawn from database1. You want the user to be able to select an arbitrary number of these messages and save them to a file? I will stop here. If you still need help, please, try to be more specific. It is hard to design the entire application from this brief description. Perhaps you should pick a single task and ask how that one task might be accomplished. We could proceed from there.
Seeking HP (RMB) Basic/Workstation 300 (5.x or 6.x)
Greetings: Anyone still have RMB for HP300s? We'd like to run 5.x or 6.x on some 9000/320s at the Museum. All replies much appreciated. (remove the NYETSPAMs to reply) Michael Grigoni Cybertheque Museum
How to do an automatic detection, if an external device is insert or not (on a card reader)
Dear All, I have updated from LV6 to LV7. With this update the VI volume information cause an error if the volume which is ask for is an external card reader and the memory card is not inserted. I received the message: Please Insert a Card in drive. This is what I do not need, because I would like to have this information without a user input (!) Any Ideas, [EMAIL PROTECTED]
Clusters: How to remove the 3D shaded background?
I'm currently building an automated test and cal setup using labview. Here I have loads of input fields and indicators that causes a sea of variables. That sea has now turned into an overwhelming ocean that is anoying to rok with. Whenever I insert a local varable has to slect which item the var should point to the list is two screen heigths long. To avoid this I've decided to group them in clusters. however hee I've encountered something very anoying: I do not want the 3D shading (like a an engraved area) around my fields that make up the cluster. Howe do I make a plain background? I've looked everywhere (at leat that's what I think) but can't find out how to change it. I refuse to believe that I have to settle with an ugly layout with loads of ingoing shaded boxes around my fields. Hope that somebody outthere can help me. Cheers, Martin
Re: Stopping Labview when it has to search for a file...?
One suggestion I have is to add c:\ as the first directory for LabVIEW to search through. You can do this by selecting Tools Options Paths VI Search Path. I have done this and it will REALLY slow down the search. Doing this may have side-effects you don't want. If you have multiple versions of your VIs/DLLs stored other places on your C: drive, you just told LV it was OK to load them from there if it finds them first. To stop the searching, empty the search path. If the VI/DLL isn't in memory or on disk where it is supposed to be, LV will put up the dialog asking you to find it and perform no searching on its own. Most likely, you want to do this once or twice to discover what has been misplaced, so that it can be resaved to point to the new location, or relocated to be where the saved VI wants it, then turn the search path back on. It gets really annoying and seems lazy when LV always wants you to find things for it. One other point is that the initial DLL is something LV is in control of loading, but once it asks the OS to load a DLL, the dependent DLLs are something out of LV's control. The OS will do its own searching, but without a dialog. Greg McKaskle
Re: do all the sub VIs in a reentrant VI need to be reentrant?
I wasnt sure I thought a VI that was made reentrant actually would with every instance will have its own copies of all the subVIs in it which it would not share with anything else. As others have pointed out, the reentrant option doesn't automatically apply to subVIs. A reentrant VI can allow all callers to start executing, without having to wait for the current one to finish before another can begin. This means that the built-in nodes, and in particular, the generated code for the VI will allow for this. If the VI calls a subVI, this subVI may be reentrant, in which case the same rules apply, or it might not be. If it is not, then the callers will take turns in the subVI. There are also some built-in objects such as property nodes to the UI, that are not reentrant and must take turns making OS calls for UI. So, as you have stated, you may want to make some of your subVIs reentrant too. If you are doing this to speed up your application's execution, then here are a few things to keep in mind. Reentrancy speeds things up because the VIs waiting for VIs weren't queued up for execution. If nothing is queued up, then when the CPU goes idle, it really goes idle since there are no other tasks to swap to while waiting. Making reentrant VIs means that while one task waits on I/O or another resource other than the CPU, the CPU can get to work on the other. There is of course a limit to how much this helps, and if you look at the task manager and see that the CPU usage is low, reentrancy may allow it to go higher by listing other things the CPU can do while waiting. When it pegs, your CPU is no longer waiting for things to do, and giving it more tasks won't speed things up, it will just mean that instead of finishing something and starting another, the CPU will swap back and forth making progress in little steps. So, my rule of thumb is, if your app has low CPU usage and you want to speed it up, look to see if you have a VI used multiple places in your app that can be made reentrant. Also, keep in mind that some VIs are meant to serialize things. Instruments and other devices can get confused if multiple commands are being sent for multiple tasks. LV2 style globals are another case where it makes no sense to make them reentrant. Greg McKaskle
Re: Excell open file gives me file permission error 8 in LV
I'm making a save file ( TXT ) that could be accessed by other programs! Now when i try to test it with Excell but I always get the file permission error 8 in Labview! Some applications lock access to a file when they open it. On some of the more advanced LV File Open functions you may notice something called a deny mode. Anyway, my guess is that once Excel opens the file, it opens it for read/write, and states that nobody can open it for write purposes. Your LV program will probably be able to complete the open if you change it to open read-only, or you can figure out how to modify the open in Excel to open read-only and allow others to write to the file. Greg McKaskle
Re: How can be controled the event queue??
too. So, the subVI stops. I suppose this happens this way because the X event is waiting in the event queue until the next execution of the subVI, so I would like to know if there's any way to empty the event queue when the subVI starts executing. If you are using dynamic registration, I think you can unregister and register for the events, but another solution is to add a bit of state information. The close event will still arrive, but you will know that you are supposed to ignore it, and can return Discard as TRUE. Greg McKaskle
Re: When tryiong to install LabView 6i, I receive an error message.
I was trying to uninstall 6i so that I could install 6.1 on a Windows 98 machine. I got this error. Any suggestions? LabView 6i has been installed and working on this machine for months. Now I need to upgrade to test some new code and can't get it to work. Any help would be appreciated. Thanks Jason BEI Sensors Systems
Re: Filtering out and sending data to the correct graph depending on data identifier
Hu. Interesting. The biggest disadvantage I can see with this is that it feels more complex. I'm in the process of learning and I feel like it is easier to understand what I'm doing if I use a measure-identifier. I see that having a certain telegram format where the second data is, say, T2, I don't need the identifier anymore, but what happens when in the 16bit data-integer, if the bits match up to create the comma? Won't that throw the whole telegram off?
Re: Clusters: How to remove the 3D shaded background?
Most things in Labview ARE, if you know where to look :) By the way, in case your input clusters STILL seem too crowded, you can change the size of the windows with custom tools...also, changing the fonts in the boxes can do wonders for visibility on a crowded monitor. Grouping by color background is a big help too. Also, be sure you have your display set for the maximum resolution and color depth possible. If you end up staring at your VI for a long time, it really can make a difference. Just a few hints from the peanut gallery! Eric
text justification in table headers/cells
Dear Folks, Is there a way to programmatically set the Text justification in a table in LV 6.1? I have a table of data in which I want to set all the column headers to center justification, and yet set all the data in the cells (and in the row headers) to left justification. I can't find a way to do this programmatically, and from the UI all I can do is set it one way or the other for the whole table (cells and headers). I know this is really just a cosmetic issue, but it is something I would like to fix nonetheless. If you manually set the headers to be center justified, that only works for the headers you can see. If you scroll over, the new headers that become visible are left justified. Any ideas, anyone? Thanks in advance, Alvin Moore Alvin W. Moore Jr. Measurement Systems Programmer Research, Development, and Engineering Corning Cable Systems Hickory, NC
Clusters Linking To Invalid Parameters
I was wondering if someone could chime in on whether the issue of clusters linking to the first parameter with matching low level name and type. I will try to explain this using a main cluster contain 2 identical sub clusters which are defined by a constant. I am unbundling both the first element in the 2nd cluster and the entire 2nd sub cluster. I am then bundling the first element(Boolean) in both sub clusters with a constant. When I delete the 2nd sub cluster from the constant defining the main cluster, I encounter linking problems: 1. The unbundling of All Elements of sub cluster 2 is an invalid link(Name is black). I believe this to be correct behavior. 2. The unbundling of the first element(Boolean) in sub cluster 2 is now linked to the first element in sub cluster 1. In other words, LV created a new unintended connection. I believe this should result in an invalid link as well, just as unbundling All Elements 3. The bundling of the first element(Boolean) in sub cluster 2 is now linked to the first element in sub cluster 1. I believe this to be incorrect as well. Should be invalid. This example is trying to simulate a scenario I am having using type def clusters. I have 1 large main cluster that when I make a modification to it, I am encountering undesirable linking issues. If this description is confusing, I can forward an example in LV 6.1 to anyone that wishes. I know there were discussions on this topic last year around February, but am unaware of the current status. Is this bug reported to NI? If it has been, is it solved in future versions of LV? I am currently using LV 6.1. If someone would be gracious enough to try it with NI's latest release of LV, I would really appreciate it. Thanks in advance for any help, Dan Miller Sensor Concepts, Inc.
RE: text justification in table headers/cells
Thanks Dan, but then I would have to use a monospaced font and fiddle with the graphics much more than I want to. I was hoping there was some magic with control refs that I didn't know about that would solve the problem. Alvin. Alvin W. Moore Jr. Measurement Systems Programmer Research, Development, and Engineering Corning Cable Systems Hickory, NC Bookwalter, Dan [EMAIL PROTECTED]To: '[EMAIL PROTECTED]' [EMAIL PROTECTED] eridge.com cc: Subject: RE: text justification in table headers/cells 02/02/2004 11:48 AM Alvin You could however, use the string length and the cell width to progrmatically add spaces to the beginning of your header string Dan Bookwalter N8DCJ Hi-Stat a Stoneridge Co. 345 South Mill St. Lexington, Ohio 44904 (419) 884-1219 Phone (419) 884-4172 Direct (419) 884-4195 Fax [EMAIL PROTECTED] -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Monday, February 02, 2004 11:21 AM To: [EMAIL PROTECTED] Subject: text justification in table headers/cells Dear Folks, Is there a way to programmatically set the Text justification in a table in LV 6.1? I have a table of data in which I want to set all the column headers to center justification, and yet set all the data in the cells (and in the row headers) to left justification. I can't find a way to do this programmatically, and from the UI all I can do is set it one way or the other for the whole table (cells and headers). I know this is really just a cosmetic issue, but it is something I would like to fix nonetheless. If you manually set the headers to be center justified, that only works for the headers you can see. If you scroll over, the new headers that become visible are left justified. Any ideas, anyone? Thanks in advance, Alvin Moore Alvin W. Moore Jr. Measurement Systems Programmer Research, Development, and Engineering Corning Cable Systems Hickory, NC _ This electronic mail transmission contains confidential information intended only for the person(s) named. Any use, distribution, copying or disclosure by any other person is strictly prohibited. If you received this transmission in error, please send an electronic mail message to [EMAIL PROTECTED]
Re: Clusters Linking To Invalid Parameters
Hey Dan, Say hi to everyone at SCI for me. We saw this same behavior in earlier versions of LabVIEW but it has been fixed in LabVIEW 7. Tom At 08:52 AM 2/2/2004 -0800, Dan Miller wrote: I was wondering if someone could chime in on whether the issue of clusters linking to the first parameter with matching low level name and type. I will try to explain this using a main cluster contain 2 identical sub clusters which are defined by a constant. I am unbundling both the first element in the 2nd cluster and the entire 2nd sub cluster. I am then bundling the first element(Boolean) in both sub clusters with a constant. When I delete the 2nd sub cluster from the constant defining the main cluster, I encounter linking problems: 1. The unbundling of All Elements of sub cluster 2 is an invalid link(Name is black). I believe this to be correct behavior. 2. The unbundling of the first element(Boolean) in sub cluster 2 is now linked to the first element in sub cluster 1. In other words, LV created a new unintended connection. I believe this should result in an invalid link as well, just as unbundling All Elements 3. The bundling of the first element(Boolean) in sub cluster 2 is now linked to the first element in sub cluster 1. I believe this to be incorrect as well. Should be invalid. This example is trying to simulate a scenario I am having using type def clusters. I have 1 large main cluster that when I make a modification to it, I am encountering undesirable linking issues. If this description is confusing, I can forward an example in LV 6.1 to anyone that wishes. I know there were discussions on this topic last year around February, but am unaware of the current status. Is this bug reported to NI? If it has been, is it solved in future versions of LV? I am currently using LV 6.1. If someone would be gracious enough to try it with NI's latest release of LV, I would really appreciate it. Thanks in advance for any help, Dan Miller Sensor Concepts, Inc.
Re: [W6.1] RMS averaging with FFT Spectrum (Mag-Phase).vi
Hi folks, I know the overlapping average technology from signal analysers. In those cases I used them up to now, phase was not relevant. Now I have an idea about a different use where phase would be important. Scott's comment that phase would be meaningless if overlapping averaging is used is making me thinking. What about this: 1. Cut the long waveform stream into a number of (overlapping) pieces. 2. Use the FFT vi for each piece, which will produce amplitudes and phases for each frequency bin. 3. Average apmlitude and phase for each frequency bin separately. Would this create meaningful phase? I would guess yes, as all pieces were acquired in a consistant stream of data originally. Seems that my mathematical understanding does not reach far enough to understand this completely. Cheers Gerd
Re: Which delimiter to use for TCP functions?
Eric, Another way to approach this (and one that I use without trouble) is to send the data as ASCII text. Since your data are all numeric, you can then use a non-numeric character as your delimiter. I send strings like [abcde 0.02 1233.4 12 3.14] where abcde is a fixed length code that tells what kind of data are to follow. The receiver then just formats these strings back into numbers. Since you are not sending binary data, there is never, ever a possibility that a part of a flattened string will mimic the stop and start codons of your messages (in this case [ and ]). The downside is that if you are sending large streams of high-precision data, the number of bytes required for each message increases, and therefore the speed of transmission potentially slows. So whether you can use this will depend on how large your arrays are and how fast/busy your connection is. David Hi all, maybe someone has run into this problem before: I have a program that uses the following code: Several arrays (numeric) are flattened to strings, then the strings are concatenated (with a delimiter between each string) before it is sent to a TCP write function. On the other end, I parse the TCP read string using the match pattern with the delimiter being the same as the write side (currently a tab constant). Pretty basic, and works fine most of the time. However, it seems that sometimes a tab shows up as part of the flattened string, and confuses the match pattern into thinking this is the delimiter. This causes all kinds of havoc with the program. Is this a possible situation? Does anyone know of a good delimiter that is not one of the flattened string characters (if it exists)? Thanks in advance,=20 Eric Scott Christian, you replied: How to do it? You define an escape character (maybe really Esc=0x1B or even better a char that is unlikely to show up in your data). Than replace any occurance of this char in your original data with a sequence of escape0x1 and afterwards all occurances of delimiter with escape0x2. Send this data and perform the inverse operation before using your delimiter. Both transcodings can be transparent. I do not have VIs at hand, but exactly this is what is done when transfering our medical measurements between different 'nodes' (may those be instances of operational units, devices or even machines). A side note: You should test a set of your raw data and do a histogram of all chars therein. Use the two chars that do show up least often as escape and as delimiter. Since the array is binary data, potentially any bit pattern can appear in it. You are just making the delimiter longer to decrease the odds of a false positive. Theoretically, I could always create artificial sample data that would fail your approach. No. This is a misunderstanding. This is a failsafe aproach if done properly! I replace any occurence of the delimiter and of an Esc char with a set of two chars, where the first is that Esc char. This adds some extra chars to the string; the number of extra chars depends on the number of Esc and delimiter char in the raw string. After trancoding every occurence of Esc together with its successor is a representation of one of the original special chars as are Esc and delimiter. Actually (after sleeping over this), I think the programmatically simplest solution would be to make an array of strings, then flatten it again. To decode: you unflatten the string to an array of strings, then unflatten each string back to the numeric arrays. It is so much easier to work with arrays compared to searching through a string. You're right, but with a lot of short strings (and a more slow connection) the overhead can be very important. 4 extra bytes for every String and at least 8 extra bytes for the array and its size. Greetings from Germany! -- Uwe Frenz ~ Dr. Uwe Frenz Entwicklung getemed Medizin- und Informationtechnik AG Oderstr. 59 D-14513 Teltow Tel. +49 3328 39 42 0 Fax +49 3328 39 42 99 [EMAIL PROTECTED] WWW.Getemed.de -- David Ferster Actimetrics, Inc. 1024 Austin St., Evanston, IL 60202 http://www.actimetrics.com 847/922-2643 Phone 847/589-8103 FAX
Polynomial fit
Hi all, when making a polynomial fit on a data set with n points it should always be possible to find a n-1 degree polynomial expression that gives a mean squared error equal to 0 (well, rounding errors make this an 'almost' 0) When using the SVD algoritm in the General Plynomial Fit.vi this isn't always the case. Is this due to the qualities of the SVD algorithm ? E.g. the Givens algorithm seems more stable. My math is a little rusty so I'll appreciate comments from you math-gurus that I know reside out there. Best regards, Lars-Goran ** Confidentiality Statement and Disclaimer ** Proprietary or confidential information belonging to Gambro AB or to one of its affiliated companies may be contained in this message. If you are not the addressee indicated in this message (or responsible for the delivery of the message to such person), please do not copy or deliver this message to anyone. In such case, please destroy this message and notify the sender by reply e-mail. Please advise the sender immediately if you or your employer do not consent to Internet e-mail for messages of this kind. Opinions, conclusions and other information in this message that pertain to the sender's employer and its products and services represent the opinion of the sender and do not necessarily represent or reflect the views and opinions of the employer. ** End of Statement **
RE: Time Zone
...and if I do not have the internet toolkit? -Original Message- From: Brian Gangloff [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 04, 2004 2:02 PM To: Daniel A. Gilmore Cc: [EMAIL PROTECTED] Subject: Re: Time Zone Daniel A. Gilmore wrote: I need to save absolute time stamps to an Excel compatible CSV file and need the time zone adjustment from Universal Time to do this since the LV time stamp is in Universal Time. Is there a way in LV to get this info. If you have the internet toolkit, there is a VI that formats time according to RFC-1123. It is located here: .\vi.lib\addons\internet\utils\strutil.llb\RFC-1123 Date.vi A sub of this VI calculates the local offset from a known GMT time which provides the local difference from GMT .\vi.lib\addons\internet\utils\strutil.llb\GMT Delta.vi Brian
RE: Labview 7 gotchas
I want to thank everyone for all the suggestions. I will try them all at some point in time. Because I only get the opportunity to have access to the complete test system a couple times a month when it is in use. I have opted, for the time being, to remove Labview 7 and reinstall 6 and use an older backup copy of the source. I should be able to test everything in a couple hours when the test is started again. I got my fingers crossed. Thanks again Vic
RE: Labview 7 gotchas
It in the error log indicating that certain vi's from the user libraries, instrument drivers and of course some of the labview vi's can not be saved in 6.1. It is a fairly substantial list. Vic, -Original Message- From: Scott Hannahs [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 03, 2004 1:28 PM To: Vic Blosser; LabView (E-mail) Subject: Re: Labview 7 gotchas Saving for previous versions should work fine. What kind of errors are you getting there? -Scott
FTDI drivers
Anyone had any experience using LV to access FTDI USB chips via their D2XX drivers? David -- David Ferster Actimetrics, Inc. 1024 Austin St., Evanston, IL 60202 http://www.actimetrics.com 847/922-2643 Phone 847/589-8103 FAX
Time Zone
I need to save absolute time stamps to an Excel compatible CSV file and need the time zone adjustment from Universal Time to do this since the LV time stamp is in Universal Time. Is there a way in LV to get this info. Thanks, Dan Daniel A. Gilmore Spectral Instruments, Inc. 420 North Bonita Avenue Tucson, AZ 85745 Email: [EMAIL PROTECTED] Phone: (520)884-8821 Ext. 118 FAX: (520) 884-8803 web: www.specinst.com
RE: House Simulator (rather long but it is the weekend)
Hi John, What you propose is indeed a very useful idea, and other people have already worked on it. Check out RETScreen, developed by your very own Natural Resources of Canada, or RAPSIM, developed at Murdoch University in Australia. I bet NREL in the US has something along these lines too, but I don't know its acronym. Developing such a model is a big project I think - its not so much the technical difficulty as the huge amount of data you'd have to collect and organise. I think the packages I mentioned before are still pretty close to their research origins, so you could get inside them and modify them. I'd vote for customising an existing model rather than developing your own from scratch. Incidentally, the example project you suggested at the beginning of your email would be wildly uneconomic because photovoltaics would be a crazy choice for generating low grade heat. Thermal panels would be far cheaper, by a factor of 10 at least. As an example of a thermal collector, have a look at Solarwall (http://www.solarwall.com). You might even be able to see an example of their systems on the Bombardier plant, just down the road from you in Ville-St Laurent. Thermal storage is also vastly cheaper than electrical storage - all you need is a big pile of broken rocks that you blow warm air through, rather than a complex hydrogen electrolyser and fuel cell. Will Dr Will Keogh Visitor at the Centre for Sustainable Energy Systems Australian National University Canberra ACT 0200 Australia
[W] Image acquisition
Hello all. I'm not familiar with image acquisition and I have to communicate with a CCD camera, Photometrics CE 300, using its driver PVCAM. The camera acquires a spectrum and the only processing required is to sum horizontal or vertical lines into bins. I have LabVIEW 7 Pro and I would like to know if someone here can tell me what else is required to get this job done. Thanks Jean-Pierre Drolet Avensys.
Re: Time Zone
Daniel A. Gilmore wrote: I need to save absolute time stamps to an Excel compatible CSV file and need the time zone adjustment from Universal Time to do this since the LV time stamp is in Universal Time. Is there a way in LV to get this info. If you have the internet toolkit, there is a VI that formats time according to RFC-1123. It is located here: .\vi.lib\addons\internet\utils\strutil.llb\RFC-1123 Date.vi A sub of this VI calculates the local offset from a known GMT time which provides the local difference from GMT .\vi.lib\addons\internet\utils\strutil.llb\GMT Delta.vi Brian
Re: [W] Image acquisition
Hamid, I have to upgrade an old Turbo Pascal (DOS) application to LabVIEW with the currently perfectly working hardware. The camera is cooled with liquid N2. I've already began to write an interface to their PVCAM DLL and it shouldn't required more than a dozen of CLNs to get what I need. Thanks to those who replied. Jean-Pierre Drolet Avensys - Original Message - From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Cc: Info-LabVIEW Sent: Wednesday, February 04, 2004 3:54 PM Subject: Re: [W] Image acquisition Hi Jean-Pierre; I had to look for this particular camera (photometrics 300). I did not spend much time but it seems to me that the camera is made by Roperscientific and they also provide the frame grabber (PCI bus). By the sound of it, I guess the camera is RS170 and most probably has some special features which makes is so special! (I guess it communicates with the card). Now, I don't know what exactly you want to do? I guessed you want to write a particular program in LV. If you want to have the functionality of PVCAM (I think it is Roper's software) then you will need more information regarding their DDL's and most probably their SDK. If you can get hold of the pointer to the pixel values in the memory, (assuming you would know the image format) then the rest of the job is a piece of cake! But getting hold of that pointer may not be an easy job. What would I do? I would buy a frame grabber from NI and a compatible camera according to my application and then IMAQ 7 and viola! If you need further help please contact me Regards + Dr. Hamid R. Yazdi Federal Mogul Manufacturing technology 3935 Research park drive Ann Arbor, MI 48108 Tel: 734 222 4108
RE: auto-format numeric into string
I just answered my own question... I can set a numeric control to automatic formatting through the Format Precision dialog, and then read its Format String property, which is: %#_10g. If I use that format string for the Format Into String function, it gives me the text I want. Alternatively, I can read the control's NumText.Text property and wire that to a string - even easier. meg -Original Message- From: Meg Kay [mailto:[EMAIL PROTECTED] Sent: Thursday, February 05, 2004 2:22 PM To: '[EMAIL PROTECTED] army. mil (E-mail)' Subject: auto-format numeric into string I was so happy to get the Automatic Formatting option on numeric controls. Now is there a way to get this programmatically when using Format Into String ?? meg
Re: LV - Igor
Scott, Pipes works great on OSX and widen quite a bit the interactions between LV and OSX. Also using the System Exec.vi you can easily send applescript using osascript -e 'your applescript' If you need to run in sudo mode try this in 'System Exec.vi' to show a dialog box to enter your admin pw. osascript -e 'do shell script sudo ls with administrator privileges' Hope this help Chris From: Scott Hannahs [EMAIL PROTECTED] Date: Thu, 05 Feb 2004 09:19:33 -0500 To: [EMAIL PROTECTED], Igor Mailing List [EMAIL PROTECTED] Subject: Re: LV - Igor At 18:05 -0500 01/07/2004, Daniel Flatin wrote: David Thomson wrote: A colleague of mine wants to write data from LabVIEW into files of Igor waves to analyze in Igor. I told him that I could find such conversion VI's, as I had used them years ago. You could also do this with AppleScript, and I am sure there is some other option on that other platform, but Igor's batch approach relieves you of having to manage a third programming environment. Also note that with the embedded commands in an Igor text file you can customize the processing for each data file. The advantage of using the text route is that all your code can be in G or in Igor's scripting language, ensuring both human readability and platform portability. I have updated versions of the VIs (Gary Johnson who wrote the originals updated them I believe). But I was looking for a more direct route to pass data cleanly between LabVIEW (or any application) and Igor. At the moment I am only concerned with Mac OS X. There are some nice unix features such as named pipes that could be utilized. I was thinking that the best way to do this would be Apple events to send a script to Igor to setup a FIFO and the named channels and then have LabVIEW pipe data into the FIFO. What would be really cool is to pipe data into the FIFO from a named pipe. A background task in IGOR could read data from the pipe (in either ascii or binary) and place it in the fifo. LabVIEW could read the instruments and write the data to the named pipe as it is collected, closing the pipe when it is done. A pipe passing binary double precision floats would be fairly efficient! Any comments on the above scheme before I get around to coding it up? Possibly two pipes, one passing Igor commands and one passing data? -Scott
Re: Labview and windows 2000 Arggggh!!!
I've had this happen. Closing LabView on the source machine allowed everything to be copied (including some dlls). --todd Has anyone had any problems copying VIs on a network from one machine to another in Windows 2k? I have rebooted both machines and keep getting this irritating message from windows that it cannot copy the VI because the VI is already in use. Why, oh why, is this happening? The permissions look ok on the machine. How do I get labview to fix the right path to its files?
auto-format numeric into string
I was so happy to get the Automatic Formatting option on numeric controls. Now is there a way to get this programmatically when using Format Into String ?? meg
Agilent 5973 GC
Does anyone know what drivers are available for the Agilent 5973 GC? I've looked a little at the Agilent site and have found their Cerity software package, which interfaces through the LV DSC toolkit via OPC. Are any other drivers available? Perhaps something a bit lower-level, that doesn't use OPC? TIA, Dave - David Thomson 303-499-1973 (voice and fax) Original Code Consulting [EMAIL PROTECTED] www.originalcode.com National Instruments Alliance Program Member Certified LabVIEW Developer Certified Instrument Driver Developer - Research Scientist 303-497-3470 (voice) NOAA Aeronomy Laboratory 303-497-5373 (fax) Boulder, Colorado[EMAIL PROTECTED] - There are 10 kinds of people: those who understand binary, and those who don't.
tIMER
Hi, in LV7 I need a timers smaller than 1ms. My need is for implementing a serial protocol. Using the parallel port I get a too fast dataflow, so I need delays. Thanks NunoL
RE: Time Zone
Thanks, works like a charm. One note, 0 = 12:00 AM Jan 1, 1904 GMT. -Original Message- From: Jean-Pierre Drolet [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 04, 2004 2:46 PM To: Daniel A. Gilmore; [EMAIL PROTECTED] Subject: Re: Time Zone - Original Message - From: Daniel A. Gilmore [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Wednesday, February 04, 2004 4:17 PM Subject: RE: Time Zone ...and if I do not have the internet toolkit? Get the timestamp for LabVIEW epoch (0 = Jan 1st,1903 GMT) and get the hour. The difference from midnight is your Time Zone offset. Jean-Pierre Drolet Avensys
RE: Teststand help
You can use the input buffer to pass data in. This is a string buffer, so whatever data you send in to your VI can be decoded and used in custom Labview VI's. I have used the buffer to set up multiple conditions for a VI. I pass a string that looks like channel5,2.5,channel3,3.0 and use the searchstring.vi to look for my comma separator. You enable passing the input buffer string to your VI by checking the box Input Buffer on the specify module dialog in TestStand. You can also use the Invocation Info.ctl to give your VI's information about the test. Use them in a similar manner as the input buffer above. If you want to pass data out of a test, use the TestDataCluster.vi This VI is a cluster which bundles a Pass/Fail Flag, a Numeric Data Type, a String type, and a Report Text String. These data types correspond to the Pass/Fail Test type, numeric limit Test Type, and String Test Type. ALL of these controls should be in the TestStand.llb mentioned below, check that it is installed. One other important Note: if you make VI's that use any of the connections above, make sure the controls and indicators are wired to the VI's connector pane, otherwise you will get errors. - David Huff - DISTek Integration, Inc. www.distek.com - NI Alliance Member(319) 266-7333 - Cedar Falls, Iowa. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mahoney, Richard C Sent: Wednesday, February 04, 2004 12:58 PM To: Scott Serlin; [EMAIL PROTECTED] Subject: RE: Teststand help In LabVIEW, there are TestStand Native VI's for: Get Boolean, Set Boolean, Get String Set String Get Number, Set Number Get Variant, Set Variant etc. These are all available in the scalar, or array variety, (and I've actually created multi-dimensional array VI's also.) and these are available from the TestStand Pallet on the LV Block Diagram and Front Panel If these TestStand VI's are not available, you may need to either reinstall TS, or find the TS .llb on NI web site and download and copy it to the vi.lib directory under LV. In TS, you need to wire a sequence reference in to the LV connector from TS. You must enable the Sequence reference check box in TS's Specify module dialog. Then use the Seq Ref and wire to the TS VI's and pass data back and forth at will. The variable can be accessed via name stored on the Locals tab of any sequence. These are referenced by Locals.variablename in LV. actually, the examples are quite good for this detail... Rick Mahoney Equipment Test Design Lockheed Martin Corp Syracuse, New York 13221 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Scott Serlin Sent: Wednesday, February 04, 2004 12:03 PM To: [EMAIL PROTECTED] Subject: Teststand help Can anyone help me pass variables from my VI into teststand to run the pass/fail test? I'm able to get my VI to run but cannot get the info out of my VI and into teststand after the VI runs. How do I do this? How do I also pass that info into the pass/fail test? Any other teststand tips would be appreciate. Thanks. Scott
Re: show Global variable VI during runtime
Claude, You can either use the VI server to open the front panel of the global.vi. Or put the value of the global into a standard indicator on the front panel of a standard vi and open that to show the user. Bad idea to try to let the user alter the value of a global directly, even if it can be done. David Hi, I'm trying to show a global variable VI during runtime. Is there a way to do this? Thank You Claude -- Maschinenfabrik WIFAG Mengisen Jean-Claude Wylerringstrasse 39 Postfach 3001 CH-3014 Bern Tel. +41 (31) 339 35 39 Fax: +41 (31) 339 37 12 E- Mail: Mailto:[EMAIL PROTECTED] Der Inhalt dieser E-Mail ist vertraulich und ausschliesslich fuer den bezeichneten Adressaten bestimmt. Wenn Sie nicht der vorgesehene Adressat dieser E-Mail oder dessen Vertreter sein sollten, so beachten Sie bitte, dass jede Form der Kenntnisnahme, Veroeffentlichung, Vervielfaeltigung oder Weitergabe des Inhalts dieser E-Mail unzulaessig ist. -- David Ferster Actimetrics, Inc. 1024 Austin St., Evanston, IL 60202 http://www.actimetrics.com 847/922-2643 Phone 847/589-8103 FAX
RE: Labview 7 gotchas
An example of one of the noted problems: Vi Function - Enter information for the devices to be tested. - Display for entry of info and save to a file. For loop - it's setup to run for the number of devices to be tested. - use loop counter (add one) to indicate which device - fed to a sub vi and to spreadsheet build to send to a file. Sub Vi Function - Display several fields to allow information be entered then continue. - set up - blank fields - display which device Continuous loop - enter field information - press continue button - stop loop - pass info out of loop and out of the sub vi. - information passed to build spreadsheet record to be saved to file. All this works fine in the development environment. But after being compiled the displayed device numbers (for 6 devices) is: 1 1 2 3 4 5 In the saved file it is: 1 2 3 4 5 6 Very simple, it should work, but it doesn't. I'm lost. Worst case of magic I've ever seen. Vic,
show Global variable VI during runtime
Hi, I'm trying to show a global variable VI during runtime. Is there a way to do this? Thank You Claude -- Maschinenfabrik WIFAG Mengisen Jean-Claude Wylerringstrasse 39 Postfach 3001 CH-3014 Bern Tel. +41 (31) 339 35 39 Fax: +41 (31) 339 37 12 E- Mail: Mailto:[EMAIL PROTECTED] Der Inhalt dieser E-Mail ist vertraulich und ausschliesslich fuer den bezeichneten Adressaten bestimmt. Wenn Sie nicht der vorgesehene Adressat dieser E-Mail oder dessen Vertreter sein sollten, so beachten Sie bitte, dass jede Form der Kenntnisnahme, Veroeffentlichung, Vervielfaeltigung oder Weitergabe des Inhalts dieser E-Mail unzulaessig ist.
FTP transfers to multiple destinations
Hi, I'm working on a project that will require me to send firmware updates to multiple units. In the interest of time I need to do these downloads simultaineously. I've looked at making the FTP Get Buffer function a reentrant vi but there are also many subvi's nested within that I would probably also need to make reentrant. Is this the best way to do this or is there a better way? Ed Anton American Power Conversion Tel: 401-789-5735 ext 2190 email: [EMAIL PROTECTED] http://www.apc.com
AW: [W6.1] RMS averaging with FFT Spectrum (Mag-Phase).vi
I have a phase reference pulse once per rev which starts the acquisition. So I should get consistent phase readings for repeated measurements. However, I was wondering if it would make sense to average parts of the signal(using overlapping segments) for speeding up the averaging process. The idea is to make as much use as possible out of the data that I get into the PC. Gerd -Ursprungliche Nachricht- Von: Bruce Ammons [mailto:[EMAIL PROTECTED] Gesendet: Mittwoch, 4. Februar 2004 15:27 An: 'Gerd Rech'; [EMAIL PROTECTED] Betreff: RE: [W6.1] RMS averaging with FFT Spectrum (Mag-Phase).vi The only way to get meaningful phase is to start your acquisition at the same phase for every segment. An example of this would be an encoder pulse. If each acquisition starts at a once per rev pulse from the encoder, they will all have the same phase components. Another possibility is doing order tracking, where there is a fixed number of samples per revolution. If you shift your window by the number of samples per revolution, you will get the same phase again. Any time you have a steady stream of data with no reference point, the phase data is essentially useless. If it is a repeating signal you should be able to identify a reference point. I suppose if you don't have a hardware signal, you could use convolution to identify repeating cycles of data. If phase is important, you should have a reference signal. Bruce -- Bruce Ammons Ammons Engineering www.ammonsengineering.com (810) 687-4288 Phone (810) 687-6202 Fax -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gerd Rech Sent: Wednesday, February 04, 2004 3:36 AM To: [EMAIL PROTECTED] Subject: Re: [W6.1] RMS averaging with FFT Spectrum (Mag-Phase).vi Hi folks, I know the overlapping average technology from signal analysers. In those cases I used them up to now, phase was not relevant. Now I have an idea about a different use where phase would be important. Scott's comment that phase would be meaningless if overlapping averaging is used is making me thinking. What about this: 1. Cut the long waveform stream into a number of (overlapping) pieces. 2. Use the FFT vi for each piece, which will produce amplitudes and phases for each frequency bin. 3. Average apmlitude and phase for each frequency bin separately. Would this create meaningful phase? I would guess yes, as all pieces were acquired in a consistant stream of data originally. Seems that my mathematical understanding does not reach far enough to understand this completely. Cheers Gerd
Re: scrollbars in build executable
René, The way I do this and the way LabVIEW executables become really independent of the LabVIEW environment is to have the application run all the time by accordingly configuring the top level VI and all VIs which show their FPs upon being called. This way the scroll bars will never appear and the user will not be confused by having to activate the LV-arrow to start the application either. Just make sure the app runs from the very beginning and at the end you may close the panel when the entire application is terminated by the user like any regular application on whatever platform you run it. Happy wireworks Urs Urs Lauterburg Physics demonstrator LabVIEW wireworker Physics Institute University of Bern Switzerland Hello , I would like to be able to get rid of the frontpanel scrollbars in an LabVIEW builded executable . It is easy to disable them while the build executable is running , but when the executable isn't running I allways get these scrollbars back again. Is it some setting in the application builder or a setting in the ini-file of the build executable ?? I use LabVIEW 6.1 on an windows2000 environment if that matters . Any help will be appreciated . René Ramekers Océ-Technolgies B.V. The Netherlands
Matlab decimate function
Is there a vi out there that replicates the decimate.m function in Labview. This function basically down samples a waveform using a low pass filter. I am also looking for a upsampling function that does exactly opposite of the Matlab decimate function. In Matlab it is under interp.m
interfacing LabVIEW 7.0 with VB.NET
Ok so here is the problem. I have a program written in VB.NET that will use Microsoft Access 2000 to look up and display information from a database for the user. It is very simple code however I need this application to be able to interact with a LabVIEW 7.0 program. The goal is for the user to interface only with .NET but have a button that starts the LabVIEW program and then compares the results from the LabVIEW test with those stored in the database. Is it possible for VB.NET to communicate with LabVIEW 7.0 or should I try a differnt method? Any information would be very helpful. Thank you, xc_smooth
Re: New to Lab view! Need some Help.
Actually this is only first part of my project in which i should be able to create a vehicle file using two different data base and should be able to save it as *.vcf. (you are right dialog box must produce a file named abc.VCF) first data base only contain messages in hex format and second data base only contain names of the modules in hex as wel.At the moment I am not able to attach these files because of some fault.But I can do that tommrrow. Answer to your first question is that I do not need to keep database in MS Notepad files. You are quite right, I want the user to be presented with a list of messages but in the sub file, which is drawn from database1. At the later stage user is going to use this file to send the messages. nodes data means names of the modules e.g. power window, seat control, etc. these two do not have any direct relationship.we are going to select messages and nodes then save them as vehicle file for them to be used at later stage in the application. my phone number is 07949940740. if you need more information. thank you for your help.
Re: Panel Object xy coordinates and Multiple window list in task bar
Thanks for the window fix. The first question is just a question about the inital placement of a control/indicator. I had my application just about finished when I thought about hiding and moving controls. At which point the 'Origin' of the panel was lost. I just programmatically move a control to 0,0 and took it from there. There is no other way to find the panel origin that I can see. Cheers Mads [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] To take the second question first; you must add a key to the .ini file of the application to get rid of the extra task bar entry: HideRootWindow=True So if the application's name is Hello.exe open or create the hello.ini file and add [Hello] HideRootWindow=True The first question is a bit unclear. You can move both panel objects like controls, indicators and decorations using the position property. You can also move front panels/windows around. XY coordinates are the inputs, but they are called left (X) and top (Y). If you are moving the controls to hide/show them it would often be easier to just set the visible property.
Re: How to use a GPIB card's LabView drivers to communicate with the card?
thanks very much, i'll give it a go
Optimizing network throughput over Ethernet with TCP/IP
Hello, I am interested in optimizing TCP/IP throughput in LabVIEW. I am looking to send data between two systems at rates around 20-30mbps on a dedicated 100base-t ethernet connection. All data needs to reach the other side w/o loss. I have a few questions with regard to accomplishing this. 1. bProper use of the Built-in TCP Vis:/b When sending data between two systems, what is the best manner? I have 50KB arrays of data that I need to move from one system to the next and have been wondering whether or not I need to packetize this, making multiple calls to the TCP/IP =93write=94 function, or whether it's better to just make the call with the full 20-50KB buffer? Does LabVIEW handle this for the user? What is the most efficient way to do it? 2. bBuilt-in Limits:/b I have seen references to LabVIEW's TCP buffer size being limited to 32KB, is this correct? Is it more efficient to make direct calls to windows DLLs? See this discussion thread: a href=3Dhttp://exchange.ni.com/servlet/ProcessRequest?RHIVEID=3D101RPAGEID= =3D135HOID=3D5065000800719Ctransfering data with TCP /a Additionally, I've seen another thread where it was mentioned that there was an =93improved=94 set of TCP/IP VIs. http://www.sheldoninst.com/support.html As mentioned in this discussion thread: a href=3Dhttp://exchange.ni.com/servlet/ProcessRequest?RHIVEID=3D101RPAGEID= =3D135HOID=3D50650008001294200ms delay in windows tcp ip - how to work around? /a Has any one had any experience with these? Again, has anyone had any experience using LabVIEW to send data over the network at these rates? 3. bProtocols:/b Are there any protocols that will allow for transfer at these rates? OPC? Modbus TCP? I don't mind creating one, but I'd rather not reinvent the wheel. System information: Both systems will be running Windows XP SP1 on P4 processors with lots of RAM, so lots of processing power. The network will be going through either a crossover cable or a dedicated switch, with these computers being the only devices attached to it. One final question, would it make a difference if I went up to gigabit Ethernet? What throughput have people managed on gigabit connections? Thanks, Adam
Re: Need to Modify the Benchtop Function Generator.VI
Hello, i am a labview newbie and so its very hard to me to make this code changes by my own. So it would be nice if anyone who have modified Benchtop Function Generator.VI would send me the VI via email to [EMAIL PROTECTED] . Thanks alot Volker Kupfer Sorry for my bad english :)
Re: Does anyone know of LabView drivers for an axiomtek AX4810P (PCI-GPIB)
Matthews, Thankyou for your response. I have aquired LabView drivers for my card, which consists of a VI for each command in the GPIB command set. When I run the NI 488.2 getting started wizard it detects 488.2 software but then says that it can't find any 488.2 hardware. Windows tells me that the device (PCI card) is working properly. Does the NI 488.2 wizard and MAX only detect NI cards or should it be detecting mine? Thanks in advance for all everyone's help.
