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horatius

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Everything posted by horatius

  1. Is there are an open-source and free Firewire driver for Labview?
  2. Yes I tried already in regeneration mode. I posted it here (German Labview Forum). I can translate it if you think you can help and don't speak German. The problem was that in regeneration mode the PC worked unstable. The buffer couldn't filled as fast as necessary. The problem occured sometimes only after few hours of working. Then I tried to increase the buffer but failed. I think I didn't increase the buffer in the right way. You can look the VI (posted link above) and maybe you know how to adjust the buffer properly. Opposite in non-regeneration mode the PC works without problems or interruptions but the array length can be very large.
  3. I fill an array (left side in picture) that I want to send to DAQmxWrite (right side in picture). In practical my array has only 2 different values and an INT8 type would be sufficient. However DAQmxWrite does only accept double arrays. Therefore I have to waste memory. Is there a solution? Download File:post-11132-1244197380.vi Also it's not possible anymore to define array outputs in Mathscript as integer. Also if I have integer within the Mathscript node I'm compelled to convert them to douple type. In previous versions of LV this was possible.
  4. I solved this problem long time ago: You have to send a waveform to the output. The red line is the waveform you have to generate first. Look here: relating thread there is also a link to a German LV Forum if you want to disrupt this process
  5. I posted in another German LV forum, this seems to be the answer: http://www.labviewforum.de/index.php?s=&am...ost&p=63176
  6. When does this NIWeekSession take place? What is this? How to attend? I think the basic principles of arranging points under restrictions and connect them is already solved and discussed in mathematical journals. NI just has to applay this knowledge. Is anyone a scientist in this field and can give some literature as I don't think that NI (as a monopole) will make it public?
  7. I tested loops. I inserted DAQWrite and DAQStart in the while loop. Then I left it outside and constructed a for loop around DAQWriet/Start and While loop. I tested "Continuous sample" and "finite sample" mode. Nothing worked as I need. If I use "Finite Sample" then I get an error that I exceed the number of samples if I start the task again.
  8. Does anyone know the mathematical backgrounds of this tool? It must be a topological optimization problem like travelling-salesman-problem. It's interesting to know if there is a "best solution" or if such an algorithm only finds local minima. I'd like to know how one can optimize between minimize of total wirelength minimize number of crossings minimize number of wire edges another point: this tool should simultaneously work during creation of a block diagramm and automatically snap the objects to optimum positions like a dynamically intelligent grid
  9. I continuously output analog voltage values with a DAQ card. To obtain fast and a reliable homogeneous sampling I use the sample clock of the board and a LV waveform signal. In the waveform for each time step of the sample time the output voltage value is saved. As seen in the block diagram I can select whether the waveform content is outputted only once ("finite samples") or repetitiously ("continuous samples"). However I want to repeat it only for a defined number, let's say 100 times. I have two options: To do this I can: A) 100 times replicate the length of the waveform itself ---> insufficient memory or B) output waveform only once and repeat this procedure 100 times --> no smooth signal transmission as the device reinitializes every time No options works well as I need a homogeneous output without interrupting device initialization procedures and I have to avoid too long waveforms.
  10. yes this is easier how can I arrange both cases in one window, send me your vi!
  11. QUOTE (TobyD @ Nov 5 2008, 08:57 PM) yes, with CCT not so many mouse clicks
  12. Following the post of "ooth" I found the simplest solution. just an Event Structure with 2 cases time out case Event case Download File:post-11132-1225920945.vi
  13. Ok, I surrender Has anyone an example with an Event Structure?
  14. QUOTE (Paul_at_Lowell @ Nov 4 2008, 05:09 PM) this works very well, I get a PNG file as I want then you don't have to install this Code Capture Tool
  15. QUOTE (Paul_at_Lowell @ Nov 5 2008, 04:43 PM) then I have one frame more around my loop and the arrangement is becoming bigger and bigger and less clear but maybe someone has an easy solution
  16. I have loops with long waiting periods. If I press a button the VI should stop the current waiting cycle and continue without passing of whole waiting time. I think it's possible with Event Structure but there must be an easier way to do this.
  17. QUOTE (normandinf @ Nov 3 2008, 11:29 PM) I can't find this procedure. However Code Capture Tool worked excellent. Many thanks.
  18. for example png screenshot of the whole block diagramm screen shot shortcut of windows (Alt+Print) is not the appropriate method as it captures only the currently visible part
  19. Thanks a lot. The invoke node and the setting in VI-properties/Clear indicators worked.
  20. QUOTE This method I tried before I started this thread. The method seemed intuitively at the beginning and I tested. However it didn't work (LV 8.51). Maybe you can test with your labview.
  21. I have a lamp working as boolan indicator on my front panel. After I run my VI the PC takes some time to check the state of a device. Therefore the initial state of the lamp should be off. After checking of the device the lamp is on. However the state of the lamp changes only after the procedure irrespectively whether the lamp is initially on or off. What is an easy method to set the lamp in off state immediatly after pressing the run button?
  22. Hi! I need to grab pics at a frame rate of 60fps (this is the max frame rate of camera Basler A302b). If I use the example vi "grab and save to avi " the pitures are saved only with max.35 fps. I think the speed of the hard disk limits the frame rate. Therefore I think I have to write the pictures first to the RAM, then stop the acquistion and read out the pictures and save them to the hard disk. I couldn't find a sample VI and have no idea how to save to the RAM of the computer. Basler A302b PCI 1428 LV 8.5; IMAQ 4.0
  23. thanks however I can test it only in a few weeks why is this issue not mentioned in labview help?
  24. I have a SUB VI containing a loop with a feedback node that is resetted to a given initial value. If I call this Sub VI repeatedly the feedback node is not resetted to the initial value after the first call of the Sub VI. Instead the value of the last call of the Sub VI is retained and used as new initial value. How do I have to change the prg that for each call of the Sub VI the feedback node is set to the given initial value?
  25. I've generated a waveform array that is continously outputted to an analog voltage channel with sample clock (picture). Is there any function that checks after every full array cycle if there is any user reaction (button press ...). If no the waveform should be repeated else stopped. In my program the process can be stopped within a 100 ms interval. But the process shall only stop after a cycle is accomplished. How do I have to adapt the program?
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