Author Topic: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes  (Read 318252 times)

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Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1825 on: December 07, 2020, 09:34:32 am »
More Slope trigger tests....some not triggering due to settings used.
Screenshots should speak for themselves.

In each test you're performing, you're using a "<=" type of time definition, meaning the first transition point can occur any time between the defined time and zero before the second transition point.
No look at them again, <=, >= and both rising and falling for each.

Oh, yep, sure enough.  Awesome.


Quote
Haven't tried [-- . --] yet..........and maybe not tonight as it's getting late and needing beauty sleep !  :bullshit:

In the next 24hrs I promise.  ;)

LOL!  No worries.  Same here, actually.  It's 3:30am for me right now!  That's okay, because that's my normal schedule (I'm weird that way), but it means I'll have to pick this back up tomorrow.

If there's something in particular you'd like me to try on my end, please let me know.
« Last Edit: December 07, 2020, 09:41:56 am by kcbrown »
 

Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1826 on: December 07, 2020, 10:17:11 am »


Least I can say this is not trigged from this signal data if your previously told trigger slope etc settings are used and last 1.5ms data before trig time position is what is in CSV.

This signal that you see in the screenshot *did* cause the trigger as I defined it above to fire.  That's the point.  I see no reason it should have, but it did anyway.

No.

Perhaps some language barrier.

What I mean.
There in .CSV can not find anything what can explain this trig in this place. Btw how you know it is trigged. have you seen trig out signal just for this. So we do not even know if it is trigged or captured without true trig due to example some rare well hidden bug what now pop up in just with all your settings.

Have you tried same with analog side BW reject.
Have you tried it with more wide slope steep. Example 1ms / 2ms. Do it change situation.
Have you tried using Trigger noise reject ON. (more wide hysteresis).
Have you tried using 1x probe (now with 10x probe your real input is 50mV/div) .... oh but you have 4V DC offset...

When it do wrong looks like trig, do it happen always in same time position related to signal, same place in this slow falling edge?

So this signal data, so what can see in this CSV,  can not be source for this trig if settings are all as told and if this works as I think it is designed and done.

Also this language barrier make me wonderin this your explabnation about slope trig timing.

Long time ago after when SDS1004X-E was launched I have written quite detailed introduction to these trigger functions, but unfortunately they are all in Finnish language and google can not translate it or result is just total garbage.

When slope rise, first it meet bottom threshold hysteresis bottom threshold  level... it may cross over this level many times... but this bottom need be crossed rising direction and after this last rising cross over first time it rise cross over hysteresis upper level what is also same as this trigger type bottom threshold level... after then it start count time.  Signal is rising  and time go next it cross over upper trig threshold bottom hysteresis threshold and it may cros over it multiple times...up direction down direction until it do not drop and it continue rising... soon it first time cross over upper threshold hysteresis top level what is also  same as upper trigger threshold. If time is over minimum but under maximum it generate trigger.  Of course this timing can also explain opposite way. Result is same.


Old image from my trigger guidance material


about hysteresis, of course there need also some explanation what happen in these images bit here these are only for rise knowledge about hysteresis.

In this case riding signal do not produce trig position jumping... all overlaid single acquisitions hav eperfectly trigged.


Riding sawtooth produce different triggers because narrow normal hysteresis because its level p-p is higher that hysteresis window.  This is of course made for demonstrate this effect. Mostly situation in nature is lot of more complex due do random peaks, noise or ripple etc etc..

And without  right crossing hysteresis do not happen ok trig. This hysteresis is is included in both thresholds when trigger mode have two level thresholds.

Also in attached image hysteresis are marked. In this case no need more think hysteresis imho but just for better knowledge who do not know this.



This trig have failed/error due to reason what is unknown at this time.
Still I tiny bit wonder this fat part of trace just before wanted trigger position also its timing is fun...
« Last Edit: December 07, 2020, 02:45:56 pm by rf-loop »
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Offline ballen

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1827 on: December 07, 2020, 03:36:37 pm »
It is explained bit more but unfortunately "scrambled by natural enigma". Our "enigma" is our Finnish language what is said is second difficult after Chinese in world. 
In some images there is some english/finglish explanations. But more deep text explanations just with Finnish.
https://siglent.fi/oskilloskooppi-tietoa-sds1004x-e--wfm-speed.html

I am slowly reading through this with help from Google translate.  It's very helpful, thank you for writing it!

PS: there is a typo in the second (all yellow) table shown in Figure 1, in the line with t/div= 1ms.  Column 6 contains 1G sa/s. It should read 1M sa/s.

 
 
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Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1828 on: December 07, 2020, 09:47:49 pm »


Least I can say this is not trigged from this signal data if your previously told trigger slope etc settings are used and last 1.5ms data before trig time position is what is in CSV.

This signal that you see in the screenshot *did* cause the trigger as I defined it above to fire.  That's the point.  I see no reason it should have, but it did anyway.

No.

Perhaps some language barrier.

What I mean.
There in .CSV can not find anything what can explain this trig in this place. Btw how you know it is trigged. have you seen trig out signal just for this. So we do not even know if it is trigged or captured without true trig due to example some rare well hidden bug what now pop up in just with all your settings.

Ah.  Yes, I agree, there's nothing in the data that explains why the trigger fired.  Rest assured, what was captured *is* the result of the trigger firing.  How do I know?

  • Because I had the trigger operation mode as "normal".
  • Because (as you can see from the screenshot), I had the mask operation turned on and set to stop the scope upon violation of the mask, and the capture happens only when the trigger fires when in "normal" mode.
  • Because in the CSV you can see that the second condition (passing through 4.5V from below -- well, 4.49V is what the time zero value is.  Close enough, especially with sin(x)/x interpolation) *was* met at time zero.

I've posted at least 3 different instances of the issue, along with CSV data to back it up.  One of them was in response to Tautech when he suggested I use "single" mode to reproduce the issue.  I did, and the end result is the same: the CSV data doesn't show anything to explain why the trigger fired, but the screenshot shows clearly that it did.

At this point, I don't know what other evidence I can supply, but the conclusion from the data is clear: the slope trigger mechanism, at least when using a bracketed time range, is buggy, and will fire when it shouldn't, unless the trigger mechanism is keying off data that is *consistently* failing to land in the capture.

Quote
Have you tried same with analog side BW reject.

Limiting the bandwidth helps.  I'm running a test now to see if the issue reproduces at all with a 20 MHz bandwidth limit on the input.  But limiting the bandwidth shouldn't be necessary.  What if you're trying to find high-frequency noise in the signal?   The point here is that if noise causes the trigger to fire and the trigger mechanism exclusively uses ADC output, that noise should be present in the capture!   But it wasn't, and isn't.


Quote
Have you tried it with more wide slope steep. Example 1ms / 2ms. Do it change situation.

Good question.  I don't know.  I'll have to test that as well.   But that said, it's unclear what to expect to gain from it.  200us is plenty of time when the sample rate is 1GS/s.  It's not like that time window approaches the limitations of the speed of the scope or anything.

Quote
Have you tried using Trigger noise reject ON. (more wide hysteresis).

Yes.  It does increase the amount of time to reproduction, but I have seen the issue reproduce even with that in place.


Quote
Have you tried using 1x probe (now with 10x probe your real input is 50mV/div) .... oh but you have 4V DC offset...

I've not tried that.

Quote
When it do wrong looks like trig, do it happen always in same time position related to signal, same place in this slow falling edge?

Looks that way.


Quote
So this signal data, so what can see in this CSV,  can not be source for this trig if settings are all as told and if this works as I think it is designed and done.

Agreed.

Quote
Also this language barrier make me wonderin this your explabnation about slope trig timing.

Well, let me try explaining how I think it works a different way.

When you're using the time range option for the slope trigger, what you're really doing is defining a bounding box with a section of the bottom (when using "rising" mode) side of the box that the waveform must pass through and a corner that it must also pass through for the trigger to fire.  Like this:



The above shows the trigger configuration I used: a rising slope trigger with a time range of 1.2ms to 1.4ms, a lower voltage of 3.5V, and an upper voltage of 4.5V.  The squiggly waveform I've drawn shows a waveform segment that would correctly cause the trigger to fire.

In this case, there are two gates through which the waveform must pass in order for the trigger to fire.  The first gate is at T = -1.4ms to -1.2ms (meaning, 1.4ms to 1.2ms before the trigger fires), i.e. anywhere within that range is fine, and the threshold voltage through which the waveform must pass is 3.5V.  The second gate is the 4.5V threshold.  It must occur between 1.2ms and 1.4ms after the first threshold was passed.  If that timing requirement is met at the point the waveform passes through 4.5V, the trigger fires.

Now, it would make the most sense for a rising slope trigger to insist on a rising edge when it passes through the threshold voltages, and I happen to think that such is strictly necessary, because otherwise the trigger could fire on a rising slope that is much greater than that which the trigger conditions specify.  What *is* necessary, regardless, is that the waveform pass through the voltages in question while meeting the time requirements for each transition.

Of course, there's an additional requirement: the waveform must never pass below the 3.5V threshold at any time between T = -1.2ms and T = 0.  If it does, then that would invalidate the trigger conditions.  Another way of stating it is that the *last* time the waveform passes through the 3.5V threshold must be between 1.4ms and 1.2ms prior to the time when it passes through 4.5V.


Maybe the above makes what I've got in mind more clear.  If not, I'll do my best to clarify further.
« Last Edit: December 08, 2020, 12:49:49 am by kcbrown »
 

Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1829 on: December 08, 2020, 02:50:41 am »
Have you tried same with analog side BW reject.

So far this issue has *not* reproduced with the 20MHz bandwidth limiter enabled on the probe.  Looks to me like whatever's causing this, it's very high frequency noise that somehow doesn't appear in the capture.

I'll try some of the other things next.
 

Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1830 on: December 08, 2020, 03:56:42 am »
Have you tried it with more wide slope steep. Example 1ms / 2ms. Do it change situation.
I altered the time range to be 0.5ms to 1.5ms, and kept the voltage thresholds the same.  It made no difference -- the problem reproduced easily.
 

Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1831 on: December 08, 2020, 04:01:37 am »
The issue also reproduces with acquisition in "slow" mode, i.e. fast or slow makes no difference here.
 

Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1832 on: December 08, 2020, 04:05:44 am »
Have you tried same with analog side BW reject.

So far this issue has *not* reproduced with the 20MHz bandwidth limiter enabled on the probe.  Looks to me like whatever's causing this, it's very high frequency noise that somehow doesn't appear in the capture.

I'll try some of the other things next.

This is very strange if it do not appear in capture or captured raw ADC data. It must be there, infinitely. Without it, it do not trig. But all is possible. Also some bug in FW what cause this reason is hiding. 
Do you have FULL  .CSV or Binary data. Screen shot png and paired with this full saved sample data. Example 3 set of these pairs so that these pairs are somehow marked so that can not mix and with perfectly explained trigger setting and scope other settings (norm/Auto, possible trigger coupling filters and, trigger setup exactly and so on. (display dots/interpolatin line or sinc do not affect any thing, they are post processed.)
Because if there is really no raw ADC data what explain wrong/failed trig, it need solve what make it. These can bit look and forward to Siglent for further analysis. It is not lottery machine and it do not have its own mind what some times do irrationally something like human..
If practice and theory is not equal it tells that used application of theory is wrong or the theory itself is wrong.
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Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1833 on: December 08, 2020, 04:18:43 am »
This is very strange if it do not appear in capture or captured raw ADC data. It must be there, infinitely. Without it, it do not trig. But all is possible. Also some bug in FW what cause this reason is hiding. 
Do you have FULL  .CSV or Binary data.

Yes.  Well, I *had* it but had to reboot my computer, and didn't have them stored in a location that would survive the reboot.  But seeing how I can reproduce this essentially at will, getting the data isn't a problem at all.


Quote
Screen shot png and paired with this full saved sample data. Example 3 set of these pairs so that these pairs are somehow marked so that can not mix and with perfectly explained trigger setting and scope other settings (norm/Auto, possible trigger coupling filters and, trigger setup exactly and so on. (display dots/interpolatin line or sinc do not affect any thing, they are post processed.)

Sinc versus dots versus linear doesn't affect triggering??

OK, that raises a question: does the triggering mechanism *always* use sinc?  Or straight point-to-point?  Or something else?  It has to somehow detect that a transition has happened between acquired points, clearly, so it has to be doing some kind of interpolation for that, no?


Quote
Because if there is really no raw ADC data what explain wrong/failed trig, it need solve what make it. These can bit look and forward to Siglent for further analysis. It is not lottery machine and it do not have its own mind what some times do irrationally something like human..

Agreed.  OK, so the question then is: how do you want me to upload the data?  To where?  The resulting 7-zip archive of 14Mpoints of CSV data is far too large for uploads to this forum.
 

Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1834 on: December 08, 2020, 04:22:41 am »
Quote from: kcbrown
Quote from: rf-loop

Have you tried same with analog side BW reject.

Limiting the bandwidth helps.  I'm running a test now to see if the issue reproduces at all with a 20 MHz bandwidth limit on the input. But limiting the bandwidth shouldn't be necessary.  What if you're trying to find high-frequency noise in the signal?  The point here is that if noise causes the trigger to fire and the trigger mechanism exclusively uses ADC output, that noise should be present in the capture!   But it wasn't, and isn't.

Of course. I think you have missed this point what I try.

I try analyze this problem. Not make guide how you can use it for something.
Primary purpose when I ask you do some like this is for isolate problem ana analyze because I know bit about how it works. So I may have some logic behind example this question. But I do not tell these my internal speculations behind these for avoid some mess.

Now I know after your words many things what you have tried and no effect. Now I also know that BW limit have effect. First time we hit something what have even some effect. So... this finding is Important but what all need think due to this... but also about this finding I do not want start speculate here what it may mean or not.  But it is important finding together with these findings about settings changes what have no effect.  ;)

 
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Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1835 on: December 08, 2020, 04:26:59 am »
This is very strange if it do not appear in capture or captured raw ADC data. It must be there, infinitely. Without it, it do not trig. But all is possible. Also some bug in FW what cause this reason is hiding. 
Do you have FULL  .CSV or Binary data.

Yes.  Well, I *had* it but had to reboot my computer, and didn't have them stored in a location that would survive the reboot.  But seeing how I can reproduce this essentially at will, getting the data isn't a problem at all.


Quote
Screen shot png and paired with this full saved sample data. Example 3 set of these pairs so that these pairs are somehow marked so that can not mix and with perfectly explained trigger setting and scope other settings (norm/Auto, possible trigger coupling filters and, trigger setup exactly and so on. (display dots/interpolatin line or sinc do not affect any thing, they are post processed.)

Sinc versus dots versus linear doesn't affect triggering??

OK, that raises a question: does the triggering mechanism *always* use sinc?  Or straight point-to-point?  Or something else?  It has to somehow detect that a transition has happened between acquired points, clearly, so it has to be doing some kind of interpolation for that, no?


Quote
Because if there is really no raw ADC data what explain wrong/failed trig, it need solve what make it. These can bit look and forward to Siglent for further analysis. It is not lottery machine and it do not have its own mind what some times do irrationally something like human..

Agreed.  OK, so the question then is: how do you want me to upload the data?  To where?  The resulting 7-zip archive of 14Mpoints of CSV data is far too large for uploads to this forum.

It need think. Also it need take account that what if...  and so on..  Do you have binary data also from same acquisition what you have CSV and I do not mean small part of acq. but of course every byte from start to end.
How big your zips are for both separately.
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Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1836 on: December 08, 2020, 04:40:59 am »
It need think. Also it need take account that what if...  and so on..  Do you have binary data also from same acquisition what you have CSV and I do not mean small part of acq. but of course every byte from start to end.
How big your zips are for both separately.

Well, "zip" and "7-zip" are actually two different things.  "7-zip" does a *much* better job of compressing.  While "zip" of the 14Mpoint CSV gets me a 30 megabyte zip file, "7-zip" gets me a roughly 9 megabyte "7z" file.  Both are archive formats that can store multiple files within the archive, so they're both good for the same thing.  You can get "7-zip" from https://www.7-zip.org.

I don't know how much space an archive containing the binary format file will take.  I'll let you know.

Right now I'm running the test with the trigger bandwidth limiter enabled, and it hasn't reproduced yet (it's been running for about 30 minutes so far, with about 15K frames analyzed -- I'm using the mask function to detect a violation).  I'll let that run a bit longer before reverting back to full bandwidth on everything for the purpose of gathering the data.

The real question is where I should upload the resulting (rather large) archive files to.  Any suggestions?
 

Online bdunham7

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1837 on: December 08, 2020, 04:50:02 am »
You can try a free Box account (not Dropbox) as I don't think they are banned in China...yet...while Dropbox is.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1838 on: December 08, 2020, 04:53:30 am »
I know this all may be bit frustrating. If I have here now this scope I can try repeat this error using noises etc... but I do not have.

In this image there is 1GSa/s  1ms/div 14M memory.

There was some other image where was 500MSa/s and 2ms/div

Both show this error.

But I have not seen any test (or my far over best before date eyes have not hit) test where is native 500MSa/s sampling speed.
In this 2ms 500MSa image it is decimated samplerate.

So, can you do also test just like this image:


But change one thing. Turn just this ADC from interleaved mode to non interleaved mode so it have real 500MSa/s.
This you can do more easy than easy.
Keep 1ms and this channel. Turn Ch1  ON.  Now you see samplerate is 500MSa/s now ADC is not inteerleaved mode but normal 2 channel 500MSa mode.
As told some previous image also have 500MSa/s but is is decimated from 1GSa interleaved sampling.

It may have some difference depending how trigger engine listen these 4 x 250MHz 8 bit bus from ADC or 2 x 250MHz bus in non interleaved mode...
If it give real big difference.. it is very extremely important finding, together with this previous finding about BW reject (and case is that before BW reject in ADC data can not see any reason for wrong trig. )

Imho, both are important finding, it this change affect or if not. These can imagine are like road crosses and  how to go forward, right or left or straight.
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Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1839 on: December 08, 2020, 05:02:15 am »
It need think. Also it need take account that what if...  and so on..  Do you have binary data also from same acquisition what you have CSV and I do not mean small part of acq. but of course every byte from start to end.
How big your zips are for both separately.

Well, "zip" and "7-zip" are actually two different things.  "7-zip" does a *much* better job of compressing.  While "zip" of the 14Mpoint CSV gets me a 30 megabyte zip file, "7-zip" gets me a roughly 9 megabyte "7z" file.  Both are archive formats that can store multiple files within the archive, so they're both good for the same thing.  You can get "7-zip" from https://www.7-zip.org.

I don't know how much space an archive containing the binary format file will take.  I'll let you know.

Right now I'm running the test with the trigger bandwidth limiter enabled, and it hasn't reproduced yet (it's been running for about 30 minutes so far, with about 15K frames analyzed -- I'm using the mask function to detect a violation).  I'll let that run a bit longer before reverting back to full bandwidth on everything for the purpose of gathering the data.

The real question is where I should upload the resulting (rather large) archive files to.  Any suggestions?

I am not just born. (ref zips)  ;)
I have used many many kind of packaging things as there have been personal computers far before IBM compatible shits.

It is fun how different result these different methods/algorithms give some times.
« Last Edit: December 08, 2020, 05:51:20 am by rf-loop »
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Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1840 on: December 08, 2020, 05:50:05 am »
It is explained bit more but unfortunately "scrambled by natural enigma". Our "enigma" is our Finnish language what is said is second difficult after Chinese in world. 
In some images there is some english/finglish explanations. But more deep text explanations just with Finnish.
https://siglent.fi/oskilloskooppi-tietoa-sds1004x-e--wfm-speed.html

I am slowly reading through this with help from Google translate.  It's very helpful, thank you for writing it!

PS: there is a typo in the second (all yellow) table shown in Figure 1, in the line with t/div= 1ms.  Column 6 contains 1G sa/s. It should read 1M sa/s.

Typing mistake corrected, thank you.
If practice and theory is not equal it tells that used application of theory is wrong or the theory itself is wrong.
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Online kcbrown

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1841 on: December 08, 2020, 06:24:37 am »
I know this all may be bit frustrating. If I have here now this scope I can try repeat this error using noises etc... but I do not have.

In this image there is 1GSa/s  1ms/div 14M memory.

There was some other image where was 500MSa/s and 2ms/div

Both show this error.

But I have not seen any test (or my far over best before date eyes have not hit) test where is native 500MSa/s sampling speed.
In this 2ms 500MSa image it is decimated samplerate.

So, can you do also test just like this image:


But change one thing. Turn just this ADC from interleaved mode to non interleaved mode so it have real 500MSa/s.
This you can do more easy than easy.
Keep 1ms and this channel. Turn Ch1  ON.  Now you see samplerate is 500MSa/s now ADC is not inteerleaved mode but normal 2 channel 500MSa mode.
As told some previous image also have 500MSa/s but is is decimated from 1GSa interleaved sampling.

It may have some difference depending how trigger engine listen these 4 x 250MHz 8 bit bus from ADC or 2 x 250MHz bus in non interleaved mode...
If it give real big difference.. it is very extremely important finding, together with this previous finding about BW reject (and case is that before BW reject in ADC data can not see any reason for wrong trig. )

Imho, both are important finding, it this change affect or if not. These can imagine are like road crosses and  how to go forward, right or left or straight.

The issue reproduces just as easily under these conditions as it does at 1GS/s.   I've captured the data for this, so I'll include it in the data dump.

I also found the original CSV from the single shot reproduction (I'd forgotten it was also still on the USB stick).
 

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1842 on: December 08, 2020, 09:50:01 am »
If you have box.com account you can PM me download link. Please name files or mark somehow other way so I know what is what.
If practice and theory is not equal it tells that used application of theory is wrong or the theory itself is wrong.
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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1843 on: December 08, 2020, 10:13:14 am »
Have you tried same with analog side BW reject.

So far this issue has *not* reproduced with the 20MHz bandwidth limiter enabled on the probe.  Looks to me like whatever's causing this, it's very high frequency noise that somehow doesn't appear in the capture.

I'll try some of the other things next.

This is very strange if it do not appear in capture or captured raw ADC data. It must be there, infinitely. Without it, it do not trig. But all is possible. Also some bug in FW what cause this reason is hiding. 
Do you have FULL  .CSV or Binary data. Screen shot png and paired with this full saved sample data. Example 3 set of these pairs so that these pairs are somehow marked so that can not mix and with perfectly explained trigger setting and scope other settings (norm/Auto, possible trigger coupling filters and, trigger setup exactly and so on. (display dots/interpolatin line or sinc do not affect any thing, they are post processed.)
Because if there is really no raw ADC data what explain wrong/failed trig, it need solve what make it. These can bit look and forward to Siglent for further analysis. It is not lottery machine and it do not have its own mind what some times do irrationally something like human..
Are we absolutely sure the trigger voltages are converted to adc values, and not let's say analog comparators? The strange thing is that when using scpi those voltages are attributes of each channel. In a complete digital situation, it would be more logical for them to be attributes of the trigger.
It could explain the behavior if they where analog... :-//
« Last Edit: December 08, 2020, 10:19:12 am by HendriXML »
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Offline rf-loop

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1844 on: December 08, 2020, 12:50:10 pm »
Have you tried same with analog side BW reject.

So far this issue has *not* reproduced with the 20MHz bandwidth limiter enabled on the probe.  Looks to me like whatever's causing this, it's very high frequency noise that somehow doesn't appear in the capture.

I'll try some of the other things next.

This is very strange if it do not appear in capture or captured raw ADC data. It must be there, infinitely. Without it, it do not trig. But all is possible. Also some bug in FW what cause this reason is hiding. 
Do you have FULL  .CSV or Binary data. Screen shot png and paired with this full saved sample data. Example 3 set of these pairs so that these pairs are somehow marked so that can not mix and with perfectly explained trigger setting and scope other settings (norm/Auto, possible trigger coupling filters and, trigger setup exactly and so on. (display dots/interpolatin line or sinc do not affect any thing, they are post processed.)
Because if there is really no raw ADC data what explain wrong/failed trig, it need solve what make it. These can bit look and forward to Siglent for further analysis. It is not lottery machine and it do not have its own mind what some times do irrationally something like human..
Are we absolutely sure the trigger voltages are converted to adc values, and not let's say analog comparators? The strange thing is that when using scpi those voltages are attributes of each channel. In a complete digital situation, it would be more logical for them to be attributes of the trigger.
It could explain the behavior if they where analog... :-//

How many times it need say: Siglent trigger engine is totally and fully in digital side.
If you do not believe, please take one SDS on table and parts... and try find analog trigger side pathway from it,  starting from BNC and ending to ADC input. If you today find low price segment new DPO and it use analog trigger system just throw it out from window as fast as it arrive to your hand.  It belongs to museum.
Siglent is not Keysight IV machine what still have analog side pathway trigger engine lika in old times mostly all DSO.
Also Siglent OLD DL/CNL/CNL/CFL series have analog side pathway analog comparator trigger system
All X models have  full true digital side trigger system.
Only exception is ExtTrig input in some X/X-? models. It is analog trigger  where trigger level to compatator ís done using DAC.'
If you do not know what is true digital side trigger system you can find example nice Rohde&Schwarz explanation about it.
With these kind of Trigger things what are example in Siglent and many other modern scopes is quite difficult to do with analog trigger using simple circuits.

Of course now this case rise one question. These trigger things are complex and time critical things deep inside system. Always is possible that we hit some unexpected error. These are so comples no one can never test all combinations in product development. If some say it can he do not know what he is talking. So, this possible need keep in mind until further data and tests.
We have now ONE thing what is clear it affect. BW limit. Other things like more wide slope rising time limits did not affect. Now I am not sure if he have tested if trigger filter have effect but if I understand right trigger hysteresis change did not. Also changing ADC mode from interleaved to non interleaved did not affect.
Also just this particular trigger type many conditions must be met, much more complex than some simplest possible edge trig.
If it make error and do not trig..  btw... it have made this error. We have seen it in every  image. So this need keep carefully in thinking logic.
It need think. Every time it have "trigged" wrong place... we really do not even know if it is trigged... but other thing we know sure... every this fail image we see part of signal what meet all needs for trig and it have not trigged  or least positioned it to right place... what is also important to keep in mind.
How we know it is trigged just there where is trigger time position and signal position is wrong. Think again... who ever is thinking this... how we know it IS trigged  just in this position where trigger mark is and we see this signal in wrong position in case it have failed. Who know... I do not know and trigger do not tell what and when she have done things
« Last Edit: December 08, 2020, 01:26:22 pm by rf-loop »
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Offline HendriXML

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1845 on: December 08, 2020, 01:51:34 pm »
Truth or fact is not about how many times one says something..  :o

I don't say its likely, but seeing the scope's behavior..

Also there could be benefits to analog triggers, for example when using slow "time div's", but very fast signals. At the moment I'm experimenting with that, to see how the scope responds.

Its stil running but it managed to capture a pulse of 32 ns each 700s using only 10 Samples/s (100 s/div thus 23 min/screen). That's amazing if it where only digital...

Maybe it sampling faster under water than it says?

If thats true than we have another possible explanation..(I see that the faulty trigger examples are at max sample rate, so probably not)
« Last Edit: December 08, 2020, 02:02:01 pm by HendriXML »
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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1846 on: December 08, 2020, 02:35:47 pm »
Truth or fact is not about how many times one says something..  :o

I don't say its likely, but seeing the scope's behavior..

Also there could be benefits to analog triggers, for example when using slow "time div's", but very fast signals. At the moment I'm experimenting with that, to see how the scope responds.

Its stil running but it managed to capture a pulse of 32 ns each 700s using only 10 Samples/s (100 s/div thus 23 min/screen). That's amazing if it where only digital...

Maybe it sampling faster under water than it says?

If thats true than we have another possible explanation..(I see that the faulty trigger examples are at max sample rate, so probably not)

It is true because he knows it for fact. It is fully digital, and triggering engine works with full sample rate, before decimation....
 

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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1847 on: December 08, 2020, 02:41:06 pm »
On a slow time base it is very possible to have it trigger on a pulse (2.5V, 32 nS) without seeing it happen on screen. Using a very simple edge trigger.

It probably doesn't prove much, because it is propably sampling faster under water.

Edit:
This post crossed the above one... in which my guess is already confirmed
« Last Edit: December 09, 2020, 12:42:39 am by HendriXML »
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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1848 on: December 08, 2020, 03:01:43 pm »
Truth or fact is not about how many times one says something..  :o

I don't say its likely, but seeing the scope's behavior..

Also there could be benefits to analog triggers, for example when using slow "time div's", but very fast signals. At the moment I'm experimenting with that, to see how the scope responds.

Its stil running but it managed to capture a pulse of 32 ns each 700s using only 10 Samples/s (100 s/div thus 23 min/screen). That's amazing if it where only digital...

Maybe it sampling faster under water than it says?

If thats true than we have another possible explanation..(I see that the faulty trigger examples are at max sample rate, so probably not)

ADC in SDS1000X-E works always full speed. interleaved mode full speed or non interleaved full speed. If we are now talking about SDS1000X-E. Trigger do not care your decimated samplerate at all. No one make serious oscilloscope what trig from decimated data...
If scope display show example 1ksa/s ADC works still full speed! And digital trigger engine is there.

Is now time to take some lesson how digital oscilloscopes overall works behind screen and input connectors. I think it is better to open new thread just for this if need.

« Last Edit: December 08, 2020, 03:05:50 pm by rf-loop »
If practice and theory is not equal it tells that used application of theory is wrong or the theory itself is wrong.
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Re: Siglent SDS1104X-E and SDS1204X-E Mixed Signal Oscilloscopes
« Reply #1849 on: December 08, 2020, 03:18:54 pm »
On a slow time base it is very possible to have it trigger on a pulse (2.5V, 32 nS) without seeing it happen on screen. Using a very simple edge trigger.

It probably doesn't prove much, because it is propably sampling faster under water.

That is why there exists peak detect mode. It will show those peaks..
 


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