Missing data between frames, Setup issue?

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sjett
Newbie
Posts: 5
Joined: Mon Nov 09, 2015 4:13 pm

Missing data between frames, Setup issue?

Post by sjett »

Good day,
Need Advice ,correction or guidance on my setup issue with computer, pico setting .
I am using a dell 5290 2in1 with a usb c hub that has the pico 4823 connected and a Hdmi cable to monitor.
I was diagnosing an intermittent stalling . If you look at the end of frame 23 you can see the power
supply voltage dropping on channel H and then its Zero volts at frame 24 . What do I need to change
in my set to fix this. Screen shots attached
link wave https://drive.google.com/file/d/1o1fz9l ... =drive_web
Dell 5290 2n1
usb c hub
Pico 4823
pico usb3.0 cable
HDMI cable to Monitor

Thank you for the help and learning experience.
Scott Jett
Attachments
Frame 23.jpg
frame 24.jpg

picowight
TwoWaves
TwoWaves
Posts: 164
Joined: Sat Oct 26, 2019 6:45 pm

Re: Missing data between frames, Setup issue?

Post by picowight »

The way to do this is to set a trigger for one of the channels that it will never reach - for example set the Cam sensor at 16v and set it all the way at the end (right hand side) of the screen, then set the trigger to repeat or anything except auto.
Run the scope on say 2s/div and when the data reaches the trigger it will scroll back from it so as long as you notice within 20s you stop the capture and the failure point is there.
Video on it - Pico 6 but principle is the same https://www.youtube.com/watch?v=j1mwR6c0Jho

HTH

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Rfmotors1
TwoWaves
TwoWaves
Posts: 94
Joined: Fri Aug 31, 2012 8:14 am

Re: Missing data between frames, Setup issue?

Post by Rfmotors1 »

I would like to jump into this topic, picowight has good workaround technique that works well if you are present next to the laptop at the time of the event of interest.
But I would still call it as workaround and I hope this could be solved somehow.
Ideally the frames won't have any gap between or they could be overlapping.
Let's say overlap 5% +- some deviation?
If the following frame could start recording before the first finish, even the transmission from scope to laptop would be delayed or slower, it would be fine.
The same problem is with saving to hdd, at the saving time the capture is paused. For example when using actions set to save at full buffer, if the saving could start before last frame fill up the buffer? it could be saved on time, and no waiting time could be needed? As at this case the frames are already transferred to laptop and displayed.
I have no clue if it could be done or what technical problems are preventing the delays and waiting time for saving files to hdd but at least Pico knows few guys would appreciate if it could be solved.
Thank you Pico for fantastic product, I don't complain.
Best Regards,
Roman

sjett
Newbie
Posts: 5
Joined: Mon Nov 09, 2015 4:13 pm

Re: Missing data between frames, Setup issue?

Post by sjett »

Thank you I will try it , was conserned that the shared usb c port of the hub could be causing a problem .

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