DSO4084B Bug report

xyz

Hi, here are some bugs that i found. My device info:



1. Adjust mem depth to >4K, in my case 64K. Set trigger to auto mode. Take a single shot of any waveform or just use run/stop. Turn horisontal position left and right to see waveform behind the screen. When trigger is set to auto mode waveform displays correctly from memory (pic. 1). Now switch trigger to normal mode and use horisontal position again. The waveform is cutted (pic. 2).



2. Set trigger to auto mode. Set time base to some large value, for example 500us. Take a single shot of any waveform (pic. 1). Decrease time base, in my case to 1us (pic. 2). You can see some line drawing issue. When one of line points is out of the screen, the line is not drawn. Drawing algorithm could use some interpolation to calculate missing point at x1 = 0 and x2 = screen width, and then draw line normally.



3. Using stopped waveform from previous point, change trigger to normal mode. Decrease time base to <=50us. Waveform is displayed incorrectly (pic. 1, 2).



4. Connect probe to device internal 1kHz generator. Set time base to 50ns, and set trigger to auto mode. Use single button (pic. 1). Then decrease time base to 20ns and use single button again (pic. 2), and so on (pic. 3)... See the waveform.



5. Set trigger to normal mode. Set time base <=20ns. Use single button. Horisontal position and time base controls are not working.

There are some other issues, but they probably exist due to problems that i listed above.
Also mem depth (sampling frequency) usage is kind different that i found in devices of other manufacturers (Rigol for example).
Now i have to force trigger on some detail that i want to see, and then eventualy zoom out to see the rest (using complete 64K mem).
It would be nice if i could do it in opposite way... I mean, that 64K mem was displayd default on entire screen width (without scrolling).
Then i could force trigger on some general data (usart frame for example), and then zoom in to see the details (using max sampling fequency available at current time base).

Hope to see some bug fixes soon...
Thank You.

amy

xyz replied at 2019-3-16 19:29
Thank You Amy for info. What about horizontal position knob and trigger position knob issues?

Sir, the knobs should be broken. Please contact your seller to get a new keyboard.

xyz

Thank You Amy for info. What about horizontal position knob and trigger position knob issues?

amy

_xyz_ replied at 2019-3-15 00:19
Hi Amy. It's been almost three months without any information/update. Did you decide there is no bug ...

About this bug, that is normal.
"Mem depth >4K, trigger mode normal. Connect probe to any periodic signal and set trigger level to the middle of the signal. Now move trigger level above or below your signal and use horisontal position knob. Signal i cutted. Just like in the first post  that i wrote in this thread."

In normal mode, when the signal is triggered, the oscilloscope reads one frame of data from the FPGA, and does not read all the data.
In the trigger gap, the FPGA has been re-collected, and the oscilloscope can not read the remaining data. So when you move left and right, the oscilloscope always shows a frame waveform.
It is recommended that you set the trigger mode as a single trigger.

_xyz_

Hi Amy. It's been almost three months without any information/update. Did you decide there is no bug? Or maybe it's just my device? Please, let me know... There're some other bugs that i want to report but i don't want to post them until previous ones are closed. Thank You for any info.

xyz

Hi, Any news about the update?

xyz

Hi, I have just update my oscilloscope to the latest firmware version, 20181208.
What I noticed is that horizonatl position knob and trigger position knob are not responsive anymore.
If you turn a knob slowly then it works "almost" fine, but if you turn it a little too fast then it is not working, or even works in opposite direction.
Vertical position knobs are working fine on all four channels...

Also this one is still not repaird:

Mem depth >4K, trigger mode normal. Connect probe to any periodic signal and set trigger level to the middle of the signal. Now move trigger level above or below your signal and use horisontal position knob. Signal is cutted. Just like in the first post that i wrote in this thread.

Maybe I didn't explain it preciseley. I know that the exaple that i wrote above is not what you normally do with your oscilloscope, but it shows the problem...
Imagine that you have some periodic signal, single pulse or frame and it appears every 1 minute period.
When it appears, oscilloscope triggers it, and then 1 minute without trigger.
If you now try to move signal horizontally you will see that only 4k data of the signal is displayed, even if i have mem. depth set to >4k.

xyz

Hi, here is some feedback to the latest update (firmware 1.1.2(180608.0)).
Bugs that i reported above are fixed except this one:

Mem depth >4K, trigger mode normal. Connect probe to any periodic signal and set trigger level to the middle of the signal. Now move trigger level above or below your signal and use horisontal position knob. Signal i cutted. Just like in the first post  that i wrote in this thread.

amy

xyz replied at 2018-4-2 17:10
Hello, here is some feedback to the latest update, and some new bugs found.

Sir, sorry to reply you so late.
These bugs had been modifyed.
Please download in this link: http://hantek.com/en/ProductDetail_3_12166.html

amy

xyz replied at 2018-4-2 17:10
Hello, here is some feedback to the latest update, and some new bugs found.

Sir, thanks for your feedback.
We will test and reply you. Please wait for several days.