`async` ADC read

[jounathaen]

• esp32
• esp32s2
• esp32s3
• esp32c2 - Enable async ADC for C2 and H2 #3082
• esp32c3 - ADC: Add async support for oneshot reads for esp32c3 and esp32c6 #2925
• esp32c6 - ADC: Add async support for oneshot reads for esp32c3 and esp32c6 #2925
• esp32h2 - Enable async ADC for C2 and H2 #3082

[jessebraham]

Based on a quick skimming of the TRM (for the C6, at least) it appears that this should be possible by configuring APB_SARADC_ADC_DONE_INT, which "triggers when the ADC completes one data conversion". As long as we have an interrupt we can create a future for it.

Also thank you for pointing this out, this is very valuable feedback! It's easy to overlook things like this :)

[lu-zero]

I just stumbled upon this problem. I wanted to have an embassy wifi example returning its battery status and nb::block does not look like it can be used.

[nan-mu]

I also don't know much about the specific operation of adc. I want to ask, can't we simply use the current read_oneshot to encapsulate a future? I will post an example later.

Update:
Failing that, it seems like nb is refactoring their future macros, and then, I can't wrap read_oneshot without using unsafe

[nan-mu]

I'm wondering if we could have the ADC own all the pins it needs? That might make it easier to do asynchronous stuff, but it might complicate the type declaration.