Refactor Dac1/Dac2 drivers into a single Dac driver

[jessebraham]

Opening as draft as this is still completely untested and I don't know if it actually works or not yet. It should in theory.

Closes #1472.

[burrbull]

Indexes start from 0

[jessebraham]

The documentation generated for the PAC says otherwise. I don't know why but svdtools 1-indexed these.

[burrbull]

https://github.com/esp-rs/esp-pacs/blob/a7c72f72c4cc50d1595a0d5a395250306d741fed/esp32s2/src/rtc_io.rs#L132-L133

[jessebraham]

Ahh just in the SENS module I guess, it's inconsistent for whatever reason.

[bjoernQ]

I'm getting this

!! A panic occured in 'C:\Users\Bjoern\.cargo\git\checkouts\esp-pacs-175859a47098a821\a7c72f7\esp32\src\rtc_io.rs', at line 129, column 10:
index out of bounds: the len is 2 but the index is 2

Backtrace:

0x400d049d
0x400d049d - esp32::rtc_io::RegisterBlock::pad_dac
    at C:\Users\Bjoern\.cargo\git\checkouts\esp-pacs-175859a47098a821\a7c72f7\esp32\src\rtc_io.rs:129
0x400d41ca
0x400d41ca - Reset
    at C:\Users\Bjoern\.cargo\registry\src\index.crates.io-6f17d22bba15001f\xtensa-lx-rt-0.16.0\src\lib.rs:70
0x400d34f2
0x400d34f2 - ESP32Reset
    at C:\projects\review\jesse\esp-hal\esp-hal\src\soc\esp32\mod.rs:93
0x3ffffffd
0x40079a81
0x400806b5
0x400806b5 - esp_backtrace::arch::backtrace_internal
    at C:\projects\review\jesse\esp-hal\esp-backtrace\src\xtensa.rs:287
0x40007c31
0x4000073d
0x3ffffffd

Adjusting the INDEX to be zero-based (0,1) makes it work

[jessebraham]

Adjusting the INDEX to be zero-based (0,1) makes it work

I blame svd2rust, this is really misleading 😁 (It's 1-indexed in the SVD too, which is why I didn't question it)

Will fix shortly

[MabezDev]

LGTM! Thanks for taking care of this!

[bjoernQ]

LGTM and my voltmeter agrees 😄

[burrbull]

I blame svd2rust, this is really misleading 😁 (It's 1-indexed in the SVD too, which is why I didn't question it)

svd2rust uses 0-based indexing for all arrays. This does not require advanced checks, simpler for calculation and support non-numeric indices. For note, chiptool also uses 0.

There were tries earlier to use values equivalent to indices, but it was bad experience.

P.S. Enter into DAC_CW_EN_R docs. There should be note.