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Transfer Time Rapid Block Mode

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Transfer Time Rapid Block Mode

Postby Armin_T. » Wed Apr 06, 2011 2:45 pm

Hello,

I would like to know some facts about the transfer time of sampled captures by picoscopes to a pc, using rapid block mode. I made an experiment with PS 4224: I have chosen 1000 captures of a 1kHz signal with 100 Samples per capture. The sampletime was 1 second (according to the red LED on the scope), but the transfer-time to the pc was about 6 seconds. The resulting transfer-rate seems very slow (17kS/s) compared to the transfer-rate in streaming mode. Is this normal, or must I have done something wrong?
Would the transfer-time be the same with an more advanced Scope like one of the 5000 or 6000 series?

Thank you.

Regards,
Armin
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Re: Transfer Time Rapid Block Mode

Postby ziko » Thu Apr 07, 2011 1:10 pm

Hi Armin,

Rapid block differes from a normal trigger in that after it has taken all the captures it transfers to the PC. With a normal trigger after each trigger event happens it is transferred to the PC.

So the memory is first of all segmented and the trigger re-arm time between each of the waveforms is 2.5us approximately. Once it has done all the captures it transfers to the PC. So inevetebly there will be more data to transfer at the end its just the time between each of those waveforms will be reduced significantly.

Hope that makes sense.
Ziko

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Re: Transfer Time Rapid Block Mode

Postby Armin_T. » Fri Apr 08, 2011 12:30 pm

Thanks for your answer. I have another question regarding the Rapid Block Mode. The Buffer Memory of the Scopes can be divided into a limited number of Buffer Segments. I have an application that requires a record of 267k Buffer Segments with 100 Samples for each Segment an for each channel of the Scope. Which of your Scopes would be suitable for this application? I just found the PS6403 with 1 million Buffer Segments, but the other specs of that scope are much better than my application would require. Are there any cheaper scopes with this number of Buffer Segments?

Thank You!

Regards,
Armin
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Re: Transfer Time Rapid Block Mode

Postby ziko » Tue Apr 12, 2011 1:19 pm

Hi Armin,

Like you pointed out the 6403 can do this, however all our other scopes would not be able to do 267k, the next step down would be 65,536 on the 6402, 3205A, 3205B, 3206A, 3206B then 32,768 segments on the 5204 and 3204B.

Hope this helps.[url][/url]
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Re: Transfer Time Rapid Block Mode

Postby msagues » Thu Mar 15, 2012 6:29 pm

Hello!

THE SETUP:
I am working with a PicoScope 5203 in Rapid Block Mode.
I configure the oscilloscope to capture 6400 segments of 200 samples at 2 ns timebase.
The time between trigger signals is 80.2us (80.2 microseconds).
The trigger signal is introduced from the external channel and the signal level is correctly set.

THE RESULT:
The oscilloscope captures the 6400 segments, but the oscilloscope is not triggered for every trigger signal (it triggers aproximately in 1 out of 7).

THE QUESTION:
I read in the forum that the trigger re-arm time is of the order of a few microseconds. However, according to the Programmer's Guide: "using Rapid Block Mode the minimum time between waveforms can be reduced to 600 microsecods" (pg8).

Am I doing something wrong, or 600 microseconds is the real trigger re-arm time?

I would apreciate any help on this matter,

Thanks in advance,

Mikel
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Re: Transfer Time Rapid Block Mode

Postby Martyn » Fri Mar 16, 2012 8:21 am

For the 5000 series scopes the trigger re arm time is 600 us, as stated in the manual, and therefore for your waveform capturing 1 out of 7 triggers would be correct.

Our newer scopes have improved performance in this area, for example the 6000 series can re arm in 1us and capture up to 1 million segments, and the 3000a can re arm in 2us.
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Re: Transfer Time Rapid Block Mode

Postby msagues » Fri Mar 16, 2012 10:53 am

Thanks!

Your answer was very helpfull...
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