GUI leaves display artifacts


Attached is a screenshot from an actual device we’re testing with. It appears the graphing routines “wrap around” with some inputs, causing the trace to completely disappear. Because of this, some stray artifacts are left behind (see the top 1" or so of both the current and voltage graphs).

I’m measuring processor current here, so the change in current can be quite large, and quite sudden. The idle current for this processor should be around 0.5mA, while “full on” is around 7.5mA. The change (on->off or off->on) can happen in a few nS. Obviously, there are other current drains here (still looking for those!) that raise the floor to something like 8.6mA. In this mode the processor is running ~50% of the time. (8.6mA floor + 50% of 7mA is about the 11.9mA shown).

On a high note, the measured current matches very well with other test equipment we have, but Joulescope is so much easier to use!

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Thanks @TimToombs for that screenshot and description. That behavior is not something that I have seen before. I have added it to the bug list, and I will do more testing on my Ubuntu 18.04 LTS machine to see if I can duplicate it. Although it can really reduce frame rate, you can try PreferencesWaveformshow_min_maxfill in the meantime. At the very least, the artifacts will be different :wink:

I was about to say that those short glitches could be due to the 1 to 2 samples of Joulescope autoranging, but I see that you have it set to 180 mA fixed range.

I’m very happy to hear that you are finding Joulescope easy to use and useful! Thanks for taking the time to post your findings, and we’ll be working to address these types of issues.