Hacking the Rigol DHO800/900 Scope

[ebastler]

Good luck distinguishing Vmax, Vtop, Vamp and Vpp, to pick just one example. 

Maybe I have eagle eyes, but I can easily do that.

You have three people in this thread who very quickly jumped in to say that the icons alone are too difficult to distinguish. (Visually, since they are small; and cognitively, since many of them are very similar to others.) Nobody has chimed in yet to support your suggestion. Small numbers, but I dare say that a full-blown usability study would come to the same conclusion. 

[AndyBig]

This is very interesting. You need to get the application from DHO1000 and see how it is done there.

Should all be nicely laid out in the .GEL files which Rigol offers for download, shouldn't it? I certainly appreciate their open format for the firmware update files. 

Yes, I have already downloaded and unpacked the GEL for DHO1000, I’ll try to look and compare later

[RAPo]

I'm not pushing my preferences to anyone. If some people want text labels fine, I would like to do without.

Usability studies show that some people like an icon only approach, others like icon+text.
The people from Microsoft have made a special registry setting for that called TaskbarGlomLevel.

TaskbarGlomLevel change its value to 0, 1 or 2 depending on what you need it to do.
To always combine, hide labels (default): TaskbarGlomLevel = 0
Combine when taskbar is full/Show labels: TaskbarGlomLevel = 1
Never combine/Show labels: TaskbarGlomLevel = 2

You have three people in this thread who very quickly jumped in to say that the icons alone are too difficult to distinguish. (Visually, since they are small; and cognitively, since many of them are very similar to others.) Nobody has chimed in yet to support your suggestion. Small numbers, but I dare say that a full-blown usability study would come to the same conclusion.

[RAPo]

Personally I prefer just icons when we can distinguish them clearly or can customize which ones appear on the grid space available.

But when icons differ only at the pixel level then it's better to use a label.

I appreciate the effort Rigol placed in creating those icons BUT it doesn't seem to work for me. With that said, I wouldn't be able to design better icons.

The icons are good, but could have a bit higher contrast.

[Fungus]

The DHO1000 does it like this:
The firmware is supposedly the same, I wonder if we can get the DHO800 to do it like the DHO1000.

This is very interesting. You need to get the application from DHO1000 and see how it is done there.

Download the .gel file from Rigol.

[Randy222]

If you look at the measurement dialogs, Rigol has supplied a different icon for each type of measurement.

Sure. But I would not be willing to memorize the subtle details to distinguish them all, and recall which one means which. And, when in use, stare at them long enough to actually see all the little details.

A better hack is to add some code that gives a slider switch "icons on/off".

[Randy222]

This is very interesting. You need to get the application from DHO1000 and see how it is done there.

Should all be nicely laid out in the .GEL files which Rigol offers for download, shouldn't it? I certainly appreciate their open format for the firmware update files. 

Yes, I have already downloaded and unpacked the GEL for DHO1000, I’ll try to look and compare later

Most of everything that's in the dho800-900 code comes from their "same level" DSO model.

[Randy222]

A few items to note.
1) screen res. build.prop is where you go. I set mine to 1280x750 (that's 1.25x native). It displays well, lets you grab pics at that res 96dpi.
2) build.prop setting will carry into "dumpsys |grep Display" , but , actual physical screen seems to be captured by a function "fts_dt_coords", no matter the prop setting, this function gets "x(0 1024) y(0 600)". This appears to be the physcial screen layout.

Now, onto another question. What is the scope doing here (pics).
I have some noise from open probe, then I go to Stop mode, then I off/on CH1 keypad. Why the changes in the display? Is the last one just a view of last captured screen in buffer? Pics are in the 1280x750 size.

[Fungus]

Now, onto another question. What is the scope doing here (pics).

[Randy222]

Now, onto another question. What is the scope doing here (pics).

I get it, but the scope was in STOP mode for pic #2 and #3. Where did the superposition samplings go after doing a CH1 off the on ?

[Randy222]

But could we omit the names and only show (a scaled down) icon together with the value on one line?

Icons that are one line of text high will simply not be legible on the screen.

Maybe I didn't express myself quite right, but if you take the current icon height (so the same viewing as we are used to) and place the values next to it, it can work.

See the image (Attachment Link)

You think too well of my ability to modify the application )))

Remember Pipi Longstocking: “I have never tried that before, so I think I should definitely be able to do that.” 

I was checking this out on my 804. But, instead of opening a Measure side tray I just open a Measure Window, add some measurements, and that can give way more info than the side tray can, withouit icons. Measure Window has each measurement already expanded. I do notice though that some values get truncated in side-by-side windows, but you can move it to above-below view so that the truncate gets removed, it's like "153...mv" in side-side view will then be "153.52mv" in the above-below windowing view.

So, although the icons thing for side tray does allow more stuff in the side tray, not sure if we need to remove icons there. If you need so many measures, then use the Measure Window and just use side tray Measure for one or three measures. Measure Window allows you to see all the stats for that measurement without expanding the item in side tray, which then pushes the other measures out of view.

I guess in some ways the UI is flexible, just depends on how you want or need to view data on the screen.

[AceyTech]

...not sure if we need to remove icons there. If you need so many measures, then use the Measure Window and just use side tray Measure for one or three measures.

...And "640K ought to be enough for anyone."
   -B. Gates

[AceyTech]

The DHO1000 does it like this:
The firmware is supposedly the same, I wonder if we can get the DHO800 to do it like the DHO1000.

This is very interesting. You need to get the application from DHO1000 and see how it is done there.

Download the .gel file from Rigol.

@Fungus, I read that as they were saying: "Hey, that's a great idea.  Maybe you could 'Download the .gel file from Rigol.', roll up your sleeves and pitch in on the effort".

And before you attack me ad hominem;
I would love to contribute on the Android hacks, and I'm trying to learn like @AndyBig did, but I'm not very capable yet.

[shapirus]

Measure window is awfully large, taking half of the waveform display area. It works for some situations, but for others a small sidebar works better.

[AceyTech]

A few items to note.
1) screen res. build.prop is where you go. I set mine to 1280x750 (that's 1.25x native). It displays well, lets you grab pics at that res 96dpi.
2) build.prop setting will carry into "dumpsys |grep Display" , but , actual physical screen seems to be captured by a function "fts_dt_coords", no matter the prop setting, this function gets "x(0 1024) y(0 600)". This appears to be the physcial screen layout.

Can you write up a step/step guide for editing build.prop for those of us not super great at Android/Linux hackin'?  I'm pretty good with things now, but it's frustrating trying to parse thru exabytes of crap that may/not be applicable to a particular model.  I'm sure others would like something as well.

Now, onto another question. What is the scope doing here (pics).
I have some noise from open probe, then I go to Stop mode, then I off/on CH1 keypad. Why the changes in the display? Is the last one just a view of last captured screen in buffer? Pics are in the 1280x750 size.

I can't check on my scope right now, but here's a theory:

Can you try that exact same experiment on the 1K calibration signal? 

It sounds like you're stopping acquisition of a spurious noise signal source and expecting the same results.  Try a known repetitive source.

[Mechatrommer]

with a bit of practise that is not too hard. Rigol did a good job on the icons, and if you add a measurement, you'll see the corresponding icon.

Good luck distinguishing Vmax, Vtop, Vamp and Vpp, to pick just one example. 

Maybe I have eagle eyes, but I can easily do that.

my condolence to you, did you get the eagle eyes from operation? afaik human should have human eye and eagle cant type in forum... but anyway funny aside... my aging eyes luckily still can distinguish too... except not sure what they represent, i didnt rely too much on small icons... this proved eagle eye conundrum..

[ebastler]

I get it, but the scope was in STOP mode for pic #2 and #3. Where did the superposition samplings go after doing a CH1 off the on ?

Your switching CH1 off has cleared from the screen buffer the picture of the multiple, overlaid CH1 traces.  So when you switch CH1 on again, the only data the scope has to display is the most recent capture (from the capture data buffer), and that's what it shows you.

I.e. it falls back onto the same information it would show you right away upon stopping if you had disabled the "waveform freeze", as described in the manual section Fungus has shared.

[Randy222]

I get it, but the scope was in STOP mode for pic #2 and #3. Where did the superposition samplings go after doing a CH1 off the on ?

Your switching CH1 off has cleared from the screen buffer the picture of the multiple, overlaid CH1 traces.  So when you switch CH1 on again, the only data the scope has to display is the most recent capture (from the capture data buffer), and that's what it shows you.

I.e. it falls back onto the same information it would show you right away upon stopping if you had disabled the "waveform freeze", as described in the manual section Fungus has shared.

Not sure, only because that last capture trace from buffer is always a smaller clean capture? Why is it never one of the other more erratic looking items?

[ebastler]

Not sure, only because that last capture trace from buffer is always a smaller clean capture? Why is it never one of the other more erratic looking items?

The "erratic looking items" are the overlay of many traces taken in succession, with intensities weighted by how often a certain pixels sees a trace, and how long ago the last trace hit it. That mimics the behavior of analog CRT scopes. It lets you see which types of traces are frequent and which ones represent rare events. Called "digital phosphor technology" or similar by the scope manufacturers, it was a big step forward in digital scopes, especially when it became available in affordable ones about 10 years ago.

All the individual sweeps look like the "clean" one in your third screenshot.

May I recommend that you spend a bit more time with the scope part of your DHO, and less with the Android part?    Otherwise you might have saved yourself a lot of money by buying a cheap tablet instead of the scope...

[Randy222]

Measure window is awfully large, taking half of the waveform display area. It works for some situations, but for others a small sidebar works better.

Not true. The waveform display remains the same, that's just a window that gets shrunk to 1/2 the LCD display.
But yeah, it shrinks the waveform window. Pros & Cons. I guess Rigol calls it "flexible" views.

But if you jam 6 Measures in side Tray "measure", when you expand one it will force the ones below down and some will fall out of view. Measure Window you can see all the expanded Measures at the same time. Pros & Cons.

Rigol almost got UI right. They should just code in some on/off sliders and allow the user to have icons or not. Or better yet, code the APK to read a "style" xml file from /rigol/data/ where you can edit your own styles or "skin", this way everyone can run their UI their own way.

[Randy222]

Not sure, only because that last capture trace from buffer is always a smaller clean capture? Why is it never one of the other more erratic looking items?

The "erratic looking items" are the overlay of many traces taken in succession, with intensities weighted by how often a certain pixels sees a trace, and how long ago the last trace hit it. That mimics the behavior of analog CRT scopes. It lets you see which types of traces are frequent and which ones represent rare events. Called "digital phosphor technology" or similar by the scope manufacturers, it was a big step forward in digital scopes, especially when it became available in affordable ones about 10 years ago.

All the individual sweeps look like the "clean" one in your third screenshot.

May I recommend that you spend a bit more time with the scope part of your DHO, and less with the Android part?    Otherwise you might have saved yourself a lot of money by buying a cheap tablet instead of the scope...

I uderstand the individual traces are overlayed.

I think you missued what I was saying.

My observation was rather straightforward. None of the erratic looking individual traces ever are displayed after turning CH back On. Given how bright the screen in with all the overlay traces (a blob of color), I never get one of the bigger/larger traces when CH goes back to On.

[ebastler]

My observation was rather straightforward. None of the erratic looking individual traces ever are displayed after turning CH back On. Given how bright the screen in with all the overlay traces (a blob of color), I never get one of the bigger/larger traces when CH goes back to On.

As seen by the shading of the overlaid traces, the ones with higher amplitudes are rare events. They should show up as individual capture sporadically if you try often enough. Or, if you want to isolate them deliberately, you can set a higher trigger threshold.

[AceyTech]

I have some noise from open probe, then I go to Stop mode, then I off/on CH1 keypad. Why the changes in the display? Is the last one just a view of last captured screen in buffer? Pics are in the 1280x750 size.

Again, @Randy222

You're stopping acquisition of a spurious noise signal source and expecting the same results each time.
Can you duplicate this "erratic looking data" on the 1K calibration signal?  (a known repetitive source.)

[Randy222]

I have some noise from open probe, then I go to Stop mode, then I off/on CH1 keypad. Why the changes in the display? Is the last one just a view of last captured screen in buffer? Pics are in the 1280x750 size.

Again, @Randy222

You're stopping acquisition of a spurious noise signal source and expecting the same results each time.
Can you duplicate this "erratic looking data" on the 1K calibration signal?  (a known repetitive source.)

Sporadic traces are easier to see it.
A constant 1kHz sq.wave will run with a thicker horizononatl lines, then you Stop it, CH off, CH on, then the horizonatl sections become thin. Repeat that and you get the same thing with slightly different looking horizontal line. Can'y really see what I mean with a contant repeat signal.

Sporadic traces are all over the screen, I would expect some of them to show during the last step, but what I get is always a "narrow" trace kinda through the center of what was once the blob of color on the screen.

Probably all normal, was just making observation.

[Randy222]

Cooling fan noise.
I must say, the little mighty that comes with is rather noisy, I can here that whine from 20ft away. So I can understand those who say the thing is noisy.

I changed direction on making that noise go away. Instead is large external fan I will park two small fans inside under the rear cover to replace the noisy little mighty that came with. Something like the attached.