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Products => Test Equipment => Topic started by: Anand on May 21, 2015, 09:36:26 pm

Title: DS1054z bug (with poll)
Post by: Anand on May 21, 2015, 09:36:26 pm
Input signal: probe compensation 1kHz square wave from the scope
Trigger: DC / CH1 / 1.5V
Aquisition: High Res / 120k mem. depth
Horizontal position: 0ps
Horizontal scale: 50us/div

I get the attached pic.

Firmware version: 4.03 and the bug was present on 4.02.SP4
Title: Re: DS1054z bug (with poll)
Post by: kwass on May 21, 2015, 10:16:54 pm
Input signal: probe compensation 1kHz square wave from the scope
Trigger: DC / CH1 / 1.5V
Aquisition: High Res / 120k mem. depth
Horizontal position: 0ps
Horizontal scale: 50us/div

I get the attached pic.

Firmware version: 4.03 and the bug was present on 4.02.SP4

Good find, but weird how it has to be exactly those setting on the Aquire menu to see this.  IIRC people of this forum found that High Res mode was useless, so this is yet another reason to never use it.  I've added this to the bug list thread.
Title: Re: DS1054z bug (with poll)
Post by: Anand on May 21, 2015, 10:23:43 pm
Good find, but weird how it has to be exactly those setting on the Aquire menu to see this.  IIRC people of this forum found that High Res mode was useless, so this is yet another reason to never use it.
Well, I've got another bug, that dissapears when High Res is on. I'll post that soon, too.

I've added this to the bug list thread.
Sweet, thanks, I've wanted to do it myself but I didn't know if it was just me experiencing this bug so... I asked around first. :D
Title: Re: DS1054z bug (with poll)
Post by: DanielS on May 22, 2015, 01:22:33 am
That's a strangely specific bug.

And yes, I got that on my 1054Z too.

This is a strangely specific bug. It works on any channel when the same channel is used as the trigger source and only one channel is enabled at a time.

I probably would never have come across this bug on my own since I practically always use at least two channels and usually limit memory depth to 30-60k points when I save waveforms.
Title: Re: DS1054z bug (with poll)
Post by: miguelvp on May 22, 2015, 01:48:33 am
Too bad the poll doesn't have a I don't own a DS1054z so we can look at the results.
Title: Re: DS1054z bug (with poll)
Post by: alsetalokin4017 on May 22, 2015, 02:49:47 am
Yep,  mine does that too. (firmware 04.02.SP4)

I wonder if "unhacked" scopes do it.
Title: Re: DS1054z bug (with poll)
Post by: evb149 on May 22, 2015, 02:54:53 am
So the bug is that it shows the trigger point as preceding the displayed edge by a couple of hundred microseconds?
Title: Re: DS1054z bug (with poll)
Post by: kedwards22 on May 22, 2015, 06:10:06 am
I've got a brand new un-hacked scope (still using the trial time) and it has the bug.
Title: Re: DS1054z bug (with poll)
Post by: Anand on May 22, 2015, 07:22:38 am
Too bad the poll doesn't have a I don't own a DS1054z so we can look at the results.

Fixed. :D
Title: Re: DS1054z bug (with poll)
Post by: dom0 on May 22, 2015, 09:34:13 am
So the bug is that it shows the trigger point as preceding the displayed edge by a couple of hundred microseconds?

Yep
Title: Re: DS1054z bug (with poll)
Post by: alsetalokin4017 on May 22, 2015, 03:55:30 pm
Seventy-five microseconds, actually,  IF your horizontal trigger position is on the center graticule marker. Less if the trigger position is to the left, more if it is to the right of center. Seems weird that the error should depend on the screen Horizontal Position that way.

And it does it on Trailing Edge and Both Edges trigger slope settings as well.

Title: Re: DS1054z bug (with poll)
Post by: alsetalokin4017 on May 22, 2015, 04:12:52 pm
In Horizontal Zoom mode it's even stranger.

Title: Re: DS1054z bug (with poll)
Post by: Jeroen3 on May 26, 2015, 06:12:32 pm
Confirmed in DS1104Z-S. Only in High-Res mode though.
Could it be because 125MSa/s / 120 kpts = 1.04166666......?
Title: Re: DS1054z bug (with poll)
Post by: rolycat on June 01, 2015, 09:43:51 am
Too bad the poll doesn't have a I don't own a DS1054z so we can look at the results.

Fixed. :D

Why not just click the "View Results" button below the poll?
Title: Re: DS1054z bug (with poll)
Post by: Psi on June 01, 2015, 10:26:33 am
Its so specific that it could be a debug test that someone forgot to wrap with #ifdef debug
Title: Re: DS1054z bug (with poll)
Post by: jadew on June 01, 2015, 12:08:39 pm
I get this on the DS1104Z.
Title: Re: DS1054z bug (with poll)
Post by: alsetalokin4017 on June 01, 2015, 02:02:58 pm
Has anyone who is running the latest 1000 series firmware version 04.03 tried this test to see if the bug is still there?
Title: Re: DS1054z bug (with poll)
Post by: ebastler on June 01, 2015, 04:42:35 pm
Has anyone who is running the latest 1000 series firmware version 04.03 tried this test to see if the bug is still there?
Well, according to the poll above, 3 people have tried it and have all reproduced the error.
Title: Re: DS1054z bug (with poll)
Post by: alsetalokin4017 on June 01, 2015, 04:49:50 pm
Has anyone who is running the latest 1000 series firmware version 04.03 tried this test to see if the bug is still there?
Well, according to the poll above, 3 people have tried it and have all reproduced the error.

Duh... insert embarrassed smiley here ... Thanks....

Does anyone know what the 04.03 firmware actually _does_ fix (or change) then?
Title: Re: DS1054z bug (with poll)
Post by: ankerwolf on September 23, 2015, 09:08:03 am
Hello,
it is a very special bug!
I can reproduce also in Version 00.04.03.SP1
BUT
ONLY at 120kpts & H=50┬Ás
AND depends on the position of T !!!
See attached pictures.
Title: Re: DS1054z bug (with poll)
Post by: Karel on September 23, 2015, 06:51:19 pm
Yep, same here with latest firmware.
But only when one channel is switched on. When switching on multiple channels, the phenomena disappears.
Title: Re: DS1054z bug (with poll)
Post by: ankerwolf on September 23, 2015, 07:17:45 pm
But only when one channel is switched on. When switching on multiple channels, the phenomena disappears.
That is right, because of the Mem.Depth is NOT 120k !
(And the bug ist only at 120k pts)