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working of start trigger

i want to know how a start trigger starts the acquisition of data.please give me any example

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Message 1 of 6
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Do you want to know the theory behind it or are you looking for an example?

 

What hardware are you using?

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Message 2 of 6
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theory

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A typical Multifunction DAQ Card (E, M, S, X Series) is continously acquiring samples to its onboard buffer (FIFO, ringbuffer).

As soon as the Start Trigger occurs the latest value of the buffer becomes valid and all the samples available from that point of time will be transfered to the RAM via DMA.

 

 

Christian

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Hello Christian,

 

Thank you and Best Regards,

I implemented a advance Measurement and Control system using cRIO-9074
with c-Series I/O cards( NI 9217, 9411, 9264)
I have some questions about it,

(1)- Data rate from FPGA targate to host vi is too low. how can I increase
it, when I run my host VI,  sometimes all temperature sensor update at
same time and sometimes one by one, can you please give me some hint, how
can I correct it, I used two FIFOs for NI-9411 digital pulses, I put all
Digital input  and all analog output and input in a seperate while loop in
FPGA targate VI.

(2)- I have to write that data to analyse for further result. I tried all
possible way to write data including wite to spreadsheet.vi, write to
text.vi, Data storage.vi, Write to measurement.vi. All this VI work
efficientlywhen it run individualy, But when I connect this VI to
writedata from FPGA host VI. than it always give empty file.
 I saw your post in NI discussion forum about how to write data from
Host.vi, But still I am confuse that how can I creat a protocol between
host VI and Fpga target vi. to write the data in a file. I have nearabout
38 channel to write data.

(3)- I have to measure time difference between two digital pulses, to find
a flow rate. I am using counter for it with risisng edge shot.vi, but when
i get a timestemp when there is risisng edge for the second rising edge
how can I get timestemp. Its like i have to measure time between two
pulses, I triend waveform measurement.vi to find cycle period. but it not
worked. any other was to measure it.

I am stuck in this question since from last one month. I already followed
NI-discussion forum solution but it doesnt work. I think the way I applied
is may be wrong. 

Looking forward to hear from you soon.

Plese send an additional email copy to tpatel1313@gmail.com
 
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Message 5 of 6
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Hi,

 

I think the way you are looking for support does not work via the forums. From what you wrote we have to make to many assumptions to give you hints. And I think hints won't help you.

So please call your local NI Office for support. We offer professional services so that an engineer will assist you.

 

 

Thanks,

Christian

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