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[shingarov]

Trying to run openhantek from current master with 5200A.
Firmware is successfully uploaded and the program starts and the scope starts data acquisition (green led flashing); when changing voltage limits, relays click when they should.
However, the ui draws no lines whatsoever.
I inserted some debug print statements to see what code is even reached. For example, I inserted a debug print at the beginning of retrieveChannelLevelData() and device->controlRead() is called successfully but control only gets to that point once at the beginning of execution. I also inserted another print at the beginning of PostProcessing::input() and that function is never reached.
Any suggestions how to debug this further?

[davidgraeff]

There were a lot of changes to make the 6022 work. And nobody had a 5200 to test the changes with.
Could you debug step after data acquisition to see where it gets lost?

[shingarov]

You mean stepping in gdb? Yeah I can do that although I think it's going to be painful because I am not familiar with the openhantek codebase.

I am thinking about maybe an alternate approach, to start with a commit which is known to work with 5200 and bisect.

Do you know of a commit when the 5200 worked?

[davidgraeff]

Bisect is sometimes a good approach, yes. Not in this case though. There are a lot of style/format and file move code changes since the very original OpenHantek version.
I would not recommend a pure gdb stepping. Use QtCreator/VisualStudio for fast code navigation while stepping.

Start here: https://github.com/OpenHantek/openhantek/blob/master/openhantek/src/hantekdso/hantekdsocontrol.cpp#L175 in HantekDsoControl::getSamples(unsigned &previousSampleCount)

• See if getSamples actually returns raw data and not erroring out.

This should return back to the state machine in https://github.com/OpenHantek/openhantek/blob/master/openhantek/src/hantekdso/hantekdsocontrol.cpp#L1209:

        case CAPTURE_READY5200: {
            std::vector<unsigned char> rawData = this->getSamples(expectedSampleCount);
            if (this->_samplingStarted) {
                convertRawDataToSamples(rawData);
                emit samplesAvailable(&result);
            }
        }

• See if convertRawDataToSamples does something with the raw data and not erroring out.

As soon as samplesAvailable is emitted, the data should arrive in the post processing. I do not expect a problem there, 'cause it works for other DSOs.

[henrik1g]

Did you have any success? I have a similar problem with the DSO-2250. Some very old versions of openhantek work. But anything current fails with symptoms similar to yours.
(Firmware upload, green led, relays clicking, all there, but no data on the screen)

[milahu]

Use QtCreator/VisualStudio for fast code navigation while stepping.

thanks, will try that

I have a similar problem with the DSO-2250.

same here

i only see the voltage curve for math (CH1+CH2) but no voltage curve for CH1
CH1 is connected to CAL (calibration signal), 1KHz square wave 2Vpp
CH2 is connected to GND

spectrum for CH1 and math is visible

i use version 45521b4 cos my GPU only supports GLSL 1.20

$ glxinfo | grep -i "shading language"
OpenGL shading language version string: 1.20
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 1.0.16

[Ho-Ro]

Unfortunately this repo is not supported at the moment (#277), but you can try this hint from #221:

You can check if my environment magic from above can help you:
$ MESA_GL_VERSION_OVERRIDE=3.2 MESA_GLSL_VERSION_OVERRIDE=150 OpenHantek

Otherwise please try the glscope.cpp part of this commit: OpenHantek/OpenHantek6022@97540df
If it works you should implement a run-time check for the OpenGL version and select the appropriate shader code: OpenHantek/OpenHantek6022@727950b

[milahu]

MESA_GL_VERSION_OVERRIDE=3.2 MESA_GLSL_VERSION_OVERRIDE=150

yes! its working now (version e7e0c7b), i just have to wait 5 seconds for the GUI to load
tried it before, but gave up too quick
is it a good idea to automate this hack? (more aggressive detection of GLSL support)

version 97540df works without the env-variables
but only with the --useGLES flag, also 5 seconds for app start
without that flag it fails with QOpenGLShader::link: error: vertex shader lacks `main'

[Ho-Ro]

IIRC I started from this patch that enabled OpenGL SL versions < 1.50. I added the version detection later because there was a report about regressions with (much) higher OpenGL SL versions (>2.00 ?). But you could try for your system.
My Debian stable on a ThinkPad T400 with Intel graphic reports 1.20 capability even if the installed OpenGL version supports at least 1.50.
I do not know much about OpenGL SL programming, it was a simple C&P from @coozoo.

Martin