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PicoLog sample time

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PicoLog sample time

Postby PaulF » Wed Jan 20, 2010 12:07 pm

I am using a PicoLog 1012 with PicoLog R 5.20.9.
With a Sample interval of 5 minutes, as many samples as possible & 288 samples this should be a total period of 24 hours, this run actually completes in 22 Hrs 54 minutes. A sample interval of 1 second, as many samples as possible & 3600 samples completes in 58 mins 25 secs. A sample interval of 1 second, single sample & 3600 samples completed in 1 Hr 6 mins.
Can you throw any light on where the timing innacuracy could be comming from & how it can be improved.
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Re: PicoLog sample time

Postby PeterF » Fri Feb 19, 2010 1:55 pm

Hi,
We are taking a look at this, to see what the problem can be.
Regards,
PeterF.
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Re: PicoLog sample time

Postby nogaluca » Tue Sep 21, 2010 7:10 am

Hello,
I've got a PicoLog-1216 and I'm writing a Visual Basic .NET software to control it. I can achieve 1us sampling rate using one single channel, but I've noticed that it is impossible to capture samples in a time-windows less than 32us. Could somebody tell me why, please?

Luca N.
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Re: PicoLog sample time

Postby ziko » Tue Sep 21, 2010 1:12 pm

How are you writing your code? What functions are you using? Are you working in block mode or Streaming mode? What parameters are you passing?

Kind regards
Ziko

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Re: PicoLog sample time

Postby nogaluca » Tue Sep 21, 2010 1:37 pm

I'm working in block mode and I'm using Pico.Drivers.dll functions.
Under here there is the section with which I get the samples. I have to use Thread.Sleep because the function PL1000.Ready() doesn't work.... (any suggestion?)

Code: Select all
PL1000.SetTrigger(handle, False, 0, 0, 0, 0, 0, 0, 0)

PL1000.SetInterval(handle, block_time, num_of_samples, channel)

PL1000.Run(handle, num_of_samples, PL1000.BLOCK_METHOD.BM_SINGLE)

Thread.Sleep(block_time)

PL1000.GetValues(handle, PLvalues, num_of_samples, overflow_index, trigger_index)


All works fine if I use block_time>32us, or num_of_samples >32. But with smaller sampling window, the program returns me zero values.

Regards,

Luca N.
Last edited by nogaluca on Wed Sep 22, 2010 7:07 am, edited 1 time in total.
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Re: PicoLog sample time

Postby nogaluca » Wed Sep 22, 2010 6:59 am

I've tested the code more accurately and I've found that the time I wait between the Run command and the GetValues one became too short if I use a window <32us. In this case Thread.Sleep command put the thread to sleep for 32ms that maybe is too little. It is sufficient increase Thread.Sleep time.

However now the problem is Ready command that doesn't work. Without this function I can't wait the correct time needed for conversion. I have to wait always a bigger time. Could you help me to use Ready command?
Under here the code that wait for conversion but that doesn't work. It use always Pico.Drivers.dll functions.

Code: Select all
Do While ready = False
        PL1000.Ready(handle, ready)
Loop
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Re: PicoLog sample time

Postby nogaluca » Mon Oct 04, 2010 12:38 pm

Nobody knows how solve this problem? :(
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Re: PicoLog sample time

Postby gruntman » Tue Oct 05, 2010 4:43 pm

Nogaluca,

The unit is not going to work properly if you are not calling the pl1000ready function as this function polls the driver and determines when the data has been collected. If the function is not working, there must be an incorrect value getting past somewhere along the way. Attached is a quick example that I made in VB.NET...

Regards,

Richard Boyd
Crag Technologies, Inc
http://www.pc-oscilloscopes.com
Attachments
PL1000_VB.zip
PL1000 VB.Net Rough Example
(85.36 KiB) Downloaded 139 times
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Re: PicoLog sample time

Postby nogaluca » Wed Oct 06, 2010 10:37 am

Thank you a lot. If I use your function declarations all seem to work correctly. With Pico.Drivers.dll module, instead it doesn't work.

Is there an official module for function declaration for PicoLog 1000 series with all functions?

Best regards,

Luca Nogarotto
Electronic Engineer at Nidec Sole Motor Corporation S.r.l.
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