ESP32 hard reset

[Isysxp]

Apologies if this has been mentioned elsewhere and that the below is sooooo trivial:
This problem relates to using Thonny to develop lvgl_micropython apps.
Using Thonny for task based app i.e. lvgl which has listener tasks etc. is problematic in that even after a soft reset, some event driven code is still running. If you try to run the app again, the dreaded TypeError: can't convert module to int error appears. The only way to fix this is to press the reset button on the (in my case) ESP32 board which is a bit of a pain. So, a trivial fix for this is to add a very short app to another Thonny window:

import machine
machine.reset()

Then, run this app and restart the backend will get you back to a point where you can run the lvgl app again.
Hope it helps someone as using lvgl via this excellent repo with Python is so much easier than repeated app uploads to your favourite dev board!

[kdschlosser]

you cannot use soft resets because a soft reset only clears the memory and not the hardware states. The drivers have no way of being informed that a soft reset is occurring so cleanup becomes impossible to do.

[Isysxp]

Absolutely. But I think this is a problem with the IDE used to develop an app. I have so far checked PyCharm, Idle, VSCode and MuEditor and failed dismally to get a working environment for various reasons. Thonny is the only app that is easy to use. VSCode and PyCharm do provide a hardware reset option but not Thonny. The absence of a hard reset option in this dev env is unfortunate and I note your comment: thonny/thonny#3423 and my note above was partially in response to this for new chum users as it is a simple workaround.

[StephenDone]

I use a usb switch to get round the problem, as the reset button on some of my devices is hard to access. This is is, though it's discontinued now... https://amzn.eu/d/0bb2mIa8

In vscode, you can define tasks with hotkeys. I've bought a WiFi usb switch. At some point, I intend to have a task that includes cycling the usb power as part of the upload.

I use vscode with custom tasks in combination with mpremote to mount my code without needing to upload all the code each time I modify it. It's by far the best dev env I've found so far.

[Isysxp]

Hi Stephen,
Haven't seen this USB switch ... not a bad idea even if you can't get one! But your point is well made hence my original note. I am afraid my experience with VSCode is not great probably because I have too many extensions. Nonetheless, I did get it to work but with some difficulty. With this app, you can get a hard reset if you disconnect and reconnect. Once I have found a stable sequence, I can then add a script on a hot key. Despite all of this, using this repo is a lot quicker in one way for app development than the Arduino alternative using code from (eg) EEZ studio. The alternative might be GUI Guider which looks like it generates lvgl_micropython code in which case, this might be an option for a complete app design package......

[StephenDone]

Lvgl_micropython is excellent for getting up and running quickly. It is also much easier to iteratively update and test your code, compared to uploading firmware every time you want to test something.

Maybe you should start a separate discussion asking people to describe their development environments. I am sure we could all learn something by reading what people post.

[Isysxp]

I agree, this discussion can now be closed.