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basic level trigger

anyone pls help
 
i am using labview 7.1
with the vi 'basic level trigger', i need to determine the location of signal with the threshold level. for what i know, the vi can only detect once within one sampled block of data. if within one sampled block of data, it consists of many curves?with the same threshold level value, i need to determine many location(time/index), how m i going to do?
 
thanks for enlightening me
 
 
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Message 1 of 7
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If you look inside the VI, you will see that the Call Library Function Node that is being used actually returns an array of trigger locations. Index 0 is extracted but you can remove the array index function and have all of the detected trigger locations. Be sure to save the VI with a new name and in a new location.
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Message 2 of 7
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hi

thanks for the help.
sorry to disturb again. i have used the method.but it doesnt work. it still gives the same result which means only one location detected. in fact it has 2 values for each rising n falling edge.

i have gone into the basic level trigger to c the index array.it indexes 0. within one sampled block of data, it may consist of of many curve(for sure many rising and falling edge). preseting y value for let say 0.04 i need to determine many locations(time/index), is any other method to detect?previously i used 'basic level trigger'

thanks for the advice.
regards

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Message 3 of 7
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Sorry. One thing that I forgot to mention is the "max number of trigger pts" input to the Call Library Function Node. This is a hidden front panel control. Right click on the terminal on the block diagram and select 'Show Control'. Change the value to some high number and try it again. I don't have the VI I modified on the computer here but I remember trying a value of -1 to see whether that setting would return all trigger locations but I can't remember if that worked or not. It's an easy thing for you to try though.
Message 4 of 7
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sorry
i have tried it but it doenst work either.
 
u told me to put the value of -1. i dun really understand.
 
if i use threshold 1d array, the output will b the same as in basic level trigger?i have tried.it is not my luck. it doesnt work either. i am at my wits end.
 
sorry for disturbing once again...
 
thanks.regards
 
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Message 5 of 7
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Here's an example that uses the modified basic trigger level detection.
Message 6 of 7
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thanks
 
it works eventually!!!billion of thanks on your willingness to help
 
regards
 
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Message 7 of 7
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