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Triggering a counter with another counter internally with 9401 (Labview 2009)

Hi ouz-

 

     You are correct that you cannot use the retriggerable property node with the digital input.  It is, however, supported for counter output tasks.  Your digital task uses the counter output as the sample clock, correct?  If so, then retriggering the counter output as the sample clock will 'retrigger' the digital input because the digital input takes samples when the counter outputs edges.

Gary P.
Applications Engineer
National Instruments
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Hi Gary,

 

Thanks for the reply. You are right that triggering clock signal also triggers the read.vi but problem is that I am looking for specific 12 bits of sensor output(in the  rising edge of 16 clock cycles ). If there is an error of missing one clock, error is cumulative since I am reading with referenced to the only rising edge clock and first falling edge of chip select. If I could achieve to trigger my read.vi at each falling edge of chip select and read 12 bits at the rising edge of clock, I have only one time error since I am referencing each 12 bit samples separately to chip select also. I hope I can explain.

 

BTW, do you have any suggestions to read or combine 12 bits together(indexing between 4th and 16th clock cysles) in an efficient way (I am reading right now bit by bit with 1-Channel N sample Read.vi). If I read 16 samples per channel each time, I can easily achieve this. However, I need to work in high frequency(around MHz) so reading only 16 samples per loop results in buffer overflow(classic -200279 error)) . I have searched and found Producer/Consumer pattern. Do you have any other suggestions? I need to read in modwise  such as my first data comes at 4th,20th,36th clock cycles(assuming no error), which may help.

 

Regards,

 

Ouz

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Hi Ouz-

 

     I think it would be best if you create a new forum post for this newer issue (since it has evolved from how to internally route a trigger into how to capture a specific number of bits from a digital signal).  This allows other users who may have encountered this issue to search your post (by the post title) and possibly get you some better help and also documents this issue for future users who may encounter the same issue.

 

     I am not sure I totally understand the issue regarding missing the clock.  The retriggering property should work fine for catching signals on multiple different edges separated by a time interval.

 

     Have a great day!

Gary P.
Applications Engineer
National Instruments
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Hi Gary,

 

Thanks for the help. I think you are right about opening a new topic since it  is different issue.

 

Have a good one, too.

 

Regards,

 

Ouz

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