RE: Redrawing XY Graphs
I would also like to know the answer for that incase anyone replying separately to John. Thanks Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain -Original Message- From: John Brohan [mailto:[EMAIL PROTECTED] Sent: Tuesday, May 11, 2004 2:33 PM To: [EMAIL PROTECTED] Subject: Redrawing XY Graphs Redrawing XY Graphs Is there any technique to add new points to an XY graph without re-drawing the whole thing? Dropping points does not seem to be an option in this application. Yours Sincerely John John Brohan National Instruments LabVIEW expert in Montreal Traders Micro "We connect all sorts of things to computers" 317 Barberry Place DDO Montreal PQ Canada H9G 1V3 Tel (514)995-3749 [EMAIL PROTECTED] http://www.TradersMicro.com/Index.htm
Serial Port
Hi I have done data acquisition using NI DAQ card for one of my projects. Right now, have a small project in which data needs to be acquired from a serial port. The system has a temperature controller unit which sends data to the serial port and needs to be collected using LabView. How different is it to configure and acquire data using serial port rather than NIDAQ card. Could anyone help me out in this? Also, this is going to be done using LabView 7 - Evaluation Version. I guess there are no restrictions while we use evaluation version. I hope all the features of a full development system could be used. Thanks for the help, Shankar
RE: Filter
Thank you for your responses. The filter now works. I had not defined the subVI as reentrant. Thanks Shankar -Original Message- From: Rolf Kalbermatter [mailto:[EMAIL PROTECTED] Sent: Sunday, February 08, 2004 10:08 AM To: 'Subramanian Shankar K' Cc: Info LabVIEW (E-mail) Subject: Re: Filter "Paul F. Sullivan" <[EMAIL PROTECTED]> wrote: >"Subramanian, Shankar, K" <[EMAIL PROTECTED]> wrote: > >>... Can a subVI say "Filter.vi" be called simultaneously with >>different input values? > >Unless a subVI is reentrant, it will finish operating on one set of >inputs before starting on another. You can call multiple copies >simultaneously but they will execute sequentially. > >If you wire your three channels of acquired data to three parallel >copies of Filter.vi and wire the filtered outputs all to the same >graph, data flow will prevent the instances of Filter.vi from running >until their respective data are ready and require then all to >complete before the graph is plotted. If all the channel data are >available at the same time, the channels will be processed one after >the other, but with no predetermined order. From the point of view of >the graph or the data acquisition, the filters will appear to run in >parallel, but the fine details will show the channels being processed >in series. One thing to watch out here is if your subVI uses uninitialized shift-registers for local storage. If you let them run in pseudo- parallel without the subVI being reentrant you will see wrong calculations as each instance will use the local storage of the previous execution as starting point for whatever calculation it does. To avoid this make the subVI reentrant and they will each maintain their own local storage data as well as execute in real parallel too, at least as far as the number of CPUs allows. Why not set any VI always reentrant? Well, reentrant VIs do not support single step and other debug operations anymore and use more system resources as you drop them multiple times in your application. Rolf Kalbermatter CIT Engineering Nederland BVtel: +31 (070) 415 9190 Treubstraat 7H fax: +31 (070) 415 9191 2288 EG Rijswijkhttp://www.citengineering.com Netherlands mailto:[EMAIL PROTECTED]
Standalone application installation
Hi I have a question regarding license issue. We actually need to install a LabView developed stand alone application for a customer. Does the customer need to buy any license before I install the RunTimeEngine or am I allowed to install the standalone in customers computer without any additional purchase of license. Thank you for the help, Shankar Subramanian
Filter
Hi, I am acquiring data from three channels of NI DAQ card and plotting in real time. I would like to know how to incorporate 5th low pass Butterworth filter to this raw signal from three channels simultaneously and plot the filtered data also in the waveform along with the raw data. I tried but I am not able to get proper output. I have one question: Can a subVI say "Filter.vi" be called simultaneously with different input values? Thank you for your help, Shankar
Second Post for Stop
Hi, I posted this once but the message did not appear. So, just posting the same message again. I have a subVI that needs an emergency stop. Once this stop is pressed, the VI should stop running. The subVI has several loops running sequentially. I want this " EmStop" button to take effect no matter at which execution point the VI is. I tried putting an altogether separate loop that runs parallel with the program and checks for the "EmStop" periodically. The condition of this loop being "EmStop not pressed - continue". Considering an experiment where "EmStop" is not pressed and the subVI is executed till the end of the program which has a normal stop button which returns it to the main VI. In such a situation the control does not transfer between subVI to main VI since the EmStop loop is still running waiting for EmStop to be depressed. Instead I wired the state of normal "Stop" along with "EmStop" using OR gate to remove this problem. In such a case, if I press on "EmStop" it does not acknowledge because the loop waits for the value of the "Stop" button to evaluate the OR function. But the value of the "Stop" button does not come till the very end as it runs in a sequence. The Stop buttons are Latch when released buttons and I guess setting up a local variable does not work. Could you let me know as to how I could do it? Thanks Shankar
EmStop
Hello, I have a subVI that needs an emergency stop. Once this stop is pressed, the VI should stop running. The subVI has several loops running sequentially. I want this " EmStop" button to take effect no matter at which execution point the VI is. I tried putting an altogether separate loop that runs parallel with the program and checks for the "EmStop" periodically. The condition of this loop being "EmStop not pressed - continue". Considering an experiment where "EmStop" is not pressed and the subVI is executed till the end of the program which has a normal stop button which returns it to the main VI. In such a situation the control does not transfer between subVI to main VI since the EmStop loop is still running waiting for EmStop to be depressed. Instead I wired the state of normal "Stop" along with "EmStop" using OR gate to remove this problem. In such a case, if I press on "EmStop" it does not acknowledge because the loop waits for the value of the "Stop" button to evaluate the OR function. But the value of the "Stop" button does not come till the very end as it runs in a sequence. The Stop buttons are Latch when released buttons and I guess setting up a local variable does not work. Could you let me know as to how I could do it? Thanks Shankar
RE: [W] File Dialog.vi only shows unseen files
I too use the FileDialog.vi to present the user with a list of files from which he can choose. I see that it presents the user with all the files in the path for opening whenever the user tries to open the file. Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain -Original Message- From: Jerome Whelan [mailto:[EMAIL PROTECTED] Sent: Thursday, January 22, 2004 8:57 AM To: Info-LabVIEW Mailing List Cc: Debra NSWC Whelan Subject: [W] File Dialog.vi only shows unseen files I am using FileDialog.vi to present to the user a list of datalog files from which to choose. This may occur more than one time during program execution. I notice that once a file has been listed and selected by the user, that file name is absent from the presented name list next time the FileDialog.vi is called. I have wired the StartPath and DataLogType inputs, other inputs unwired. Stopping and re-running the top level VI makes all file names again visible. Anyone else see this behavior?
Write to File
Hi I have a loop that acquires data from NI DAQ and writes data to a text file. 'Acquiring' and 'writing to file' stages are separate sub VIs inside a loop. As soon as set of 'N' data is acquired, it is sent to write to file subVI to write in File 'X'. The process is repeated until acquisition is done for say, "t" seconds. I wanted to write the data into two files inside the "Write to File" subVI. For this I just send a File refnum to the subVI and write data to a second file (File 'Y') after writing the first (File 'X'). I use a "flush file" command for both of them. I did not use "Copy File" because file X and Y aren't the same totally. There are other parts in the program where File X gets edited and File Y does not. I have a problem with "Scan Backlog" value that AI Read returns. When I write to one file only, scan backlog stays at zero and acquisition happens properly. When I include the code for the second file too, scan backlog increases. I removed that part alone to check whether it is because of writing to second file and it worked again. Could anyone let me know as to what I am doing wrong here? Thank you, Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain
Re:Scrollbar
Thank you for all your suggestions. I am working with the tab indicator now. Thanks Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain
RE: ScrollBar
Thanks for your reply. I think I will stack them avoiding the scrollbar as I would not need all the buttons to be visible. But just curious to know, is there any way of automating scrollbar depending on the window? Thanks Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain -Original Message- From: Kelly Bersch [mailto:[EMAIL PROTECTED] Sent: Monday, January 12, 2004 12:44 PM To: [EMAIL PROTECTED] Subject: RE: ScrollBar Are all of the buttons ever visible at one time? Could you stack the buttons and only have the one you need visible so scrolling isn't necessary? Kelly Bersch Senior Technician Anadigm Telephone:480-344-5262 Email: [EMAIL PROTECTED] http://www.Anadigm.com Anadigm - The Programmable Analog Company -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Subramanian, Shankar, K Sent: Monday, 12 January, 2004 10:26 AM To: '[EMAIL PROTECTED]' Subject: ScrollBar Hi, I have a subVI(X) that takes in inputs from the user in a particular order. I have buttons and controls hidden which become visible as and when the user has to enter the data. As this happens, certain buttons that appear are beyond the window size and user needs to press the scroll bar as he proceeds with the experiment. Is there any way I could automate the movement of the scroll bar if the hidden buttons that appear on the screen go beyond range? Also assume the buttons appear in order and are: Start-->Init-->Config-->..(Say Window ends here ,scrollbar to be used)-->..-->.--> End The next time if the MainVI calls this subVI(X), the window opens at location where the button "End" is. Actually button "End" is invisible at the start of experiment and the only button visible is "Start". So at this point, I have to scroll up and go to the Start button. Is there a way I can open a subVI FP, at particular coordinates or something similar to that such that it always shows "Start" and does an automatic scrolling? Thank you Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain
ScrollBar
Hi, I have a subVI(X) that takes in inputs from the user in a particular order. I have buttons and controls hidden which become visible as and when the user has to enter the data. As this happens, certain buttons that appear are beyond the window size and user needs to press the scroll bar as he proceeds with the experiment. Is there any way I could automate the movement of the scroll bar if the hidden buttons that appear on the screen go beyond range? Also assume the buttons appear in order and are: Start-->Init-->Config-->..(Say Window ends here ,scrollbar to be used)-->..-->.--> End The next time if the MainVI calls this subVI(X), the window opens at location where the button "End" is. Actually button "End" is invisible at the start of experiment and the only button visible is "Start". So at this point, I have to scroll up and go to the Start button. Is there a way I can open a subVI FP, at particular coordinates or something similar to that such that it always shows "Start" and does an automatic scrolling? Thank you Shankar Shankar K. Subramanian TSS ESG Northboro R&D Center Saint-Gobain
