Where's My Data !!!!! ?

Forum for discussing PicoScope version 6 (non-automotive version)
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NickA62
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Joined: Mon Oct 01, 2012 8:23 am

Where's My Data !!!!! ?

Post by NickA62 »

I am making measurements at 500kS/s or 1MS/s over a period of 5s using a 4226 picoscope. This uses 5MB of buffer memory, which is well within the scopes limit.

It all looks fine on the screen during and immediately after measurements; when I save the measurement I get a file that is about 13MB, so about the expected size for two channels. BUT when I re-load the file into picoscope the detailed data is not there. All I can see is some aggregated form of the data (ie an envelope of the waveform with a low sample rate).

What happened? Where's my data? I want the full waveform, not a summary of it. From the 13MB size of the *.psdata file it seems that the data is stored, but how can I access it?

bennog
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Location: Netherlands

Re: Where's My Data !!!!! ?

Post by bennog »

The latest beta has some issues with the screen update.

Have you tryed zooming in and out again.
This wil probably fix your problem.

Benno

NickA62
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Re: Where's My Data !!!!! ?

Post by NickA62 »

Firstly, I am using picoscope 6.6.18.8 not the latest beta.

Yes, I have tried zooming in and out, but to no avail; I can only see the agregated waveforms (envelopes). When I try to export this aggregated waveform to CSV or Matlab (in the hope of getting the data back) I get empty files. If I try to "save as" a new picoscope file, picoscope just crashes.

BUT

I repeated my measurements using "block mode", ie I reset the "slow sampling transition" to 20s so that my 5s recordings were made in full before the screen updated. (this is awkward, because there is less control of sample rate - but it's OK). The files made in this way are totally zoomable and contain the full waveform data.

There seems no reason why waveforms acquired in continuous acquisition (ie slow sampling) mode shouldn't contain the full data - the full data IS displayed on screen at the end of the test, the problems only happen when I try to save the data to file for later analysis.

SO

I have a work around, but it's not one I particularly like. So if you can help it would be appreciated.

Hitesh

Re: Where's My Data !!!!! ?

Post by Hitesh »

Hi NickA62,

Please could you update your PicoScope version to 6.6.50 (available from http://www.picotech.com/software.html) and see if the issue persists.

PicoScope 6 Beta can be installed alongside this (http://labs.picotech.com/)

If the issue persists, please send screenshots of the issue and the saved psdata file to support@picotech.com

Thanks,

NickA62
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Joined: Mon Oct 01, 2012 8:23 am

Re: Where's My Data !!!!! ?

Post by NickA62 »

Hi Hitesh,

I finally got around to updating picoscope and doing a few tests.

With picoscope 6.6.57.20 installed and using 1MS/s, 500ms per division with the slow sampling transition set to the 200ms default, I can now save waveforms "in full" and export full data to Matlab. At least, I can on my win7 x64 desktop PC; I have still to check the laptop.

Looks like 6.6.18 was a little buggy in a way that 6.6.57 is not.

Thanks for your advice & thanks for fixing the bug.

Nick A

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