3 PWM RGB and 3 PWM CCT failed

[lexius]

What happened?

ESP32 board.
When I cerate segments like: RGB, CCT, RGB, CCT, RGB, CCT - the last one will be reset on save without visible error. When I create RGB, RGB, RGB, CCT, CCT, CCT - all working fine.

To Reproduce Bug

WLED 0.15.0, 0.15.1 beta 2

Expected Behavior

6 segments must be added

Install Method

Binary from WLED.me

What version of WLED?

0.15.1 beta2

Which microcontroller/board are you seeing the problem on?

ESP32

Relevant log/trace output

Anything else?

No response

Code of Conduct

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[blazoncek]

Please use debug build and dump serial output while ESP reboots and then dump serial output when saving configuration.

[blazoncek]

I think I know what's causing this issue and there is not much that can be done (as it is too complicated to implement in UI properly).

@DedeHai & @willmmiles can you take a look? I think it has to do with the fact that CCT channels need to be aligned to even numbers. See pin manager, LEDC allocation.

[DedeHai]

yes, highly likely that it's caused by the timer-alignment required for CCT. To solve it, it would need to be re-ordered with some logic to best consolidate timer use in all possible use cases.

[willmmiles]

Yup, looks like it's a channel allocation issue. I don't think this is a UI problem so much as a "how to process a config" concern. It's basically the same challenge as parallel I2S: we cannot assume that buses are independent -- there are shared resources and allocation matters. The "right answer" is to have a phase after config parsing but before bus implementation creation where resource mappings can be planned and reordered.

Although I suppose the root UI concern -- demonstrated here, actually! -- is that unresolvable configs don't tell the user what went wrong, it just "silently" drops something. It might be worth thinking about implementing a validation endpoint to make the UI easy.