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Sine wave generator resets at random times
Posted: Fri Mar 03, 2023 6:58 pm
by barrowes
When I set the red pitayas output to be a sine wave at around 260 kHz, it seems to work, but when I sample that sinewave with channel 1, for example, I get the sine wave but every now and then the sine wave output seems to reset itself in a glitch that ruins the phase right in the middle of the 16 K buffer that I acquire. Please see the attached Matlab plots, and pic of matlab code. Tried to attach pictures but it says the board attachment quota has been reached.
https://drive.google.com/file/d/1w_O5nK ... sp=sharing
https://drive.google.com/file/d/1w_HFr_ ... sp=sharing
https://drive.google.com/file/d/1wlUKfX ... sp=sharing
Is there a way I can set the sine wave output or do something to get around this glitch?
Re: Sine wave generator resets at random times
Posted: Mon Mar 06, 2023 11:37 am
by redpitaya
Dear Barrowes,
You may not have enough time between ACQ:START and ACQ:TRIG commands (Red Pitaya needs time to acquire a full buffer, which might cause issues when requesting data too quickly, especially on higher decimations - you might get old data values).
Also, keep in mind that the triggering moment is at sample number 8192. Maybe use ACQ:TRIG CH1_PE or CH1_NE together with an ACQ:TRIG:LEV 0.2 (0.2 Volts or similar).
Re: Sine wave generator resets at random times
Posted: Fri Mar 10, 2023 1:22 pm
by barrowes
It looks like this issue has gone away with a different red pitaya. We do need a little bit of time in between start and trigger, but that does not seem to be the problem with this data-transfer glitch.
For now, it looks like the problem is solved with a different red pitaya, but if it crops back up I will post again.
Re: Sine wave generator resets at random times
Posted: Mon Mar 20, 2023 10:01 am
by redpitaya
This should nt be happening, Try using the same card as before and after that, the same power supply as before to identify the source. The same for the Ethernet cable..
Re: Sine wave generator resets at random times
Posted: Thu Mar 23, 2023 9:52 pm
by lozano
Hi Red Pitaya, I work with Barrowes on the project where we are getting this glitch issue. After some time, this issue has come back again. It might have never been resolved in the first place. I might have not noticed if it occurred less at that time. I have tried the suggestions noted about adding more time and changing the trigger level but doesn't seem to work. I also have tried other test in this order.
- Switched Red Pitaya boards
- Switched from a wireless to an ethernet connection
- One by one took out other electrical components in our system, mainly amplifiers for our coils. Until there was just 2 coils and the board
- Switch from input 1 to input 2, for the sampling
- Connected "out 1" directly to both "input 1" and "input 2" respectively
- Changed the power source from a USB powerbank to the supplied wall outlet power source
I still get the glitch issue even after trying all these tests. It varies from only seeing it after every couple shots to almost every shot. Also, sometimes the glitch can only happen one time during the waveform to multiple/several times. I'm stumped on what may be causing it. My next steps are to try other red pitaya boards that we have, to see if it occurs multiple boards. I will also try communicating to the board with Python instead of Matlab, which I've been using this whole time. Very perplexed that this issue is still occurring even when I connected the outputs directly to the inputs. Is there any more insight that you may have on why we are getting this issue?
Note, I do have the boards updated to the newest version of "1.04-28". The OS specifically for the STEMlab 125-14 & STEMlab 125-10 boards.
Re: Sine wave generator resets at random times
Posted: Fri Mar 24, 2023 9:49 am
by redpitaya
lozano wrote: ↑Thu Mar 23, 2023 9:52 pm
Hi Red Pitaya, I work with Barrowes on the project where we are getting this glitch issue. After some time, this issue has come back again. It might have never been resolved in the first place. I might have not noticed if it occurred less at that time. I have tried the suggestions noted about adding more time and changing the trigger level but doesn't seem to work. I also have tried other test in this order.
- Switched Red Pitaya boards
- Switched from a wireless to an ethernet connection
- One by one took out other electrical components in our system, mainly amplifiers for our coils. Until there was just 2 coils and the board
- Switch from input 1 to input 2, for the sampling
- Connected "out 1" directly to both "input 1" and "input 2" respectively
- Changed the power source from a USB powerbank to the supplied wall outlet power source
I still get the glitch issue even after trying all these tests. It varies from only seeing it after every couple shots to almost every shot. Also, sometimes the glitch can only happen one time during the waveform to multiple/several times. I'm stumped on what may be causing it. My next steps are to try other red pitaya boards that we have, to see if it occurs multiple boards. I will also try communicating to the board with Python instead of Matlab, which I've been using this whole time. Very perplexed that this issue is still occurring even when I connected the outputs directly to the inputs. Is there any more insight that you may have on why we are getting this issue?
Note, I do have the boards updated to the newest version of "1.04-28". The OS specifically for the STEMlab 125-14 & STEMlab 125-10 boards.
Thank you for this additional information, please contact our support email and mention this thread.