Add dummy mode about openhantek6022

[Ho-Ro]

Yeah, I already thought about this enhancement, I will check what's needed to bypass the HW detection when I've got some spare time...

[Ho-Ro]

I think the proposal is still valuable but after looking at it for one hour it will take a lot of work to connect too many loose ends. When I want to test the program without my scope at hand I either take a cheap saleae LA clone, e.g. from Lcsoft. It doesn't provide usable values as there is no ADC connected to the EzUSB chip, but at least the GUI works as expected in realtime. And my most portable solution is an old and no more used DVB-T stick that's also EzUSB based. I define another 6022 model and udev rule with the new "cold" VID/PID and after uploading the FW into RAM this device looks like a 6022 (without useful data).
Maybe a volunteer wants to provide a working dummy mode as a Xmas gift. 👍

[marcizhu]

What would be required to add this feature?
I haven't looked at the code too much, but maybe adding a fake DSOModel object that generates some simple waveforms should be enough.

Another (possibly more difficult option) would be to simulate a USB hardware device from the software itself, so the main program would detect a real device and start using it as such.

[Ho-Ro]

The fake model is simple, I did this as mentioned above, also creating dummy samples is one line in hantekdsocontrol.cpp. But it's more difficult to circumvent the USB device detection and handling.
It starts there:

OpenHantek6022/openhantek/src/main.cpp

Line 134 in 1b4c059

//////// Find matching usb devices ////////

Solution would be to define a dummy device: std::unique_ptr<USBDevice> device = dummy_device; maybe derived from class USBDevice that provides a dummy_model plus some more content, but never triggers any USB communication.
The data transfer happens in hantekdsocontrol.cpp, the device is polled by a timer every 25% of expected cycle time:

OpenHantek6022/openhantek/src/hantekdso/hantekdsocontrol.cpp

Line 104 in 1b4c059

/// \brief Updates the interval of the periodic thread timer.

Please check the OpenHantek developer documentation and feel free to experiment :)

[marcizhu]

Sure! I'll take a look at it and try to add this feature to the software in the next few days! If I succeed, I'll open a PR :D

[Ho-Ro]

I implemented a demo mode with edc9a26, call it with OpenHantek --demoMode or OpenHantek -d.