frequency and duty cycle measurement
in [LabView]
|
From: Jeremy_B on 18 Jun 2008 19:10 Hi Suneel,Have a look at the example VI at this link: <a href="http://zone.ni.com/devzone/cda/epd/p/id/4149" target="_blank">http://zone.ni.com/devzone/cda/epd/p/id/4149</a> I think it will do what your looking for. It will get a waveform subset based on cursor positions on a graph, and then graph the waveform subset. You could then pass the resulting waveform into whatever processing you need.
From: svelamal on 19 Jun 2008 00:40 Thanks Jeremey, Looks like this is the ideal example.... But right now i dont have enough effort hours left to implement it to my VI's.... But for sure out of my interest i will come on the weekend and work for it... Thanks again for you help.... Now i am supporting one of our other project which need a proper timer concept... Sorry for putting here but again needed ur help... Requirement is something like this.... - A button press should start the clock (milliseconds..) - At the backend it should continue the clock. - Again a button press should stop the clock and give the time in (ms or s) - Reset the clock to 0 and again wait for the next press.. This i am trying to implement today.... Any help from your end is very much appreciable.. Cheers, Suneel
From: Jeremy_B on 19 Jun 2008 13:10 Hi Suneel, You could have your button press execute a case statement which gets the current value of the millisecond timer (Tick Count (ms) VI in the Timing palette), and then record the value again after your other button press, and then subtract the two.
From: suneelkv on 29 Jun 2008 06:40 Hi Jeremy, This is Suneel, today i tried to impement waveform_extractor.vi to my program. But unfotunately thats not working out. - As i explained you before my req is i need to take a .wav file from a path, - read it and then use this waveform extractor.vi - extract the waveform upto a particular time period and apply some functions to calculate the frequency and duty cycle. I've attached the VI where i am getting broken arrows for the same logic of waveform extraactor .vi also attached the .vi Please repair it and re-send the same Awaiting for ur reply Cheers, Suneel/svelamal Waveform_Extractor_With_Duty-Cycle1.vi: http://forums.ni.com/attachments/ni/170/335974/1/Waveform_Extractor_With_Duty-Cycle1.vi
From: JoeLabView on 29 Jun 2008 08:10
That is because you have multi-channel sound data and the output of the Sound File Read is an array of waveforms. See image below: I added an index array just to show you that there is in fact an array of waveforms. Now, the rest of the code will not be happy with dealing with a single waveform, and I do not know which channel information you want to deal with. RayR <img src="http://forums.ni.com/attachments/ni/170/335983/1/ArrayWaves.PNG"> Message Edited by JoeLabView on 06-29-2008 08:09 AM ArrayWaves.PNG: http://forums.ni.com/attachments/ni/170/335983/1/ArrayWaves.PNG |