Opamp

[Geens]

Allow for configuration of the internal opamp peripheral. Only the disabled, voltage-follower and open-loop modes are implemented. Other states can be added later on.

It's my first time implementing such a module. Feedback and remarks are more than welcome!

[pawelchcki]

hey @Geens, Thanks for implementing it! I haven't started work on Hal part of OpAmp myself, so great timing :) as I'll have use for it in my project.

In the mean time I've added OpAmp enum definitions to stm32-rs crate stm32-rs/stm32-rs#486
I think once it lands you might be able to remove some of the magic values from your PR. You can try building that crate locally and add it to local build in cargo, to play with it before its merged.

I'll appreciate any feedback on the Enum PR too - if you think anything is missing, or should be differently named.

[Geens]

Hi @pawelchcki, cool that you're working on this too. I just had a quick look at your commit and I can definitely see the advantage of using the right enum definitions. I also noticed the table you mentioned and realized I did not enable opamp 6 for the devices that have opamps 1, 2, 3, and 6.

I'll try and build with your stm32-rs branch this weekend and update to use the enum defs. Since your branch is not yet part of any release, how do we fix the dependencies for this crate? Do we just leave this pull-request open until the stm32-rs is updated?

[pawelchcki]

@Geens I'm hoping to get this reviewed quite soon, will ping the maintainer tomorrow (don't want to bother them too often).

Once it lands in stm32-rs master it will be available via https://github.com/stm32-rs/stm32-rs-nightlies - that you can use directly in HALs cargo.toml. I think if you like the Enum's it would make sense to review and wait until the stm32 is released, and only then merge this into this crate.

Actually I'll try to push the updated stm32 in my own nightly repository - could be useful for myself too.

[pawelchcki]

Ok seems it worked, feel free to use this repo/branch to work with these changes.

[dependencies.stm32g4]
git = "https://github.com/pawelchcki/stm32-rs-nightlies"
branch = "opamp"
features = ["stm32g431", "rt"]

[Geens]

@pawelchcki, The stm32g471 is missing opamp 6 in the PAC. This was mentioned in STM32G4 #486. For me, it's not really necessary so I don't mind commenting it out. But it seems like it's not hard to add it either.

Also there are no features for the stm32g491 and stm32g4a1 in this crate yet. Also not really needed for me but I would think it's better to add them sooner than later.

How would you continue?

[pawelchcki]

@pawelchcki, The stm32g471 is missing opamp 6 in the PAC. This was mentioned in STM32G4 #486. For me, it's not really necessary so I don't mind commenting it out. But it seems like it's not hard to add it either.

I'm not sure stm32g471 actually has the 6th Opamp - the manual says shoud have it, but STM Cube sources only have first 3 opamps defined there. From what I've read, sadly the STM CubeMX generated files are usually most accurate.

Also there are no features for the stm32g491 and stm32g4a1 in this crate yet. Also not really needed for me but I would think it's better to add them sooner than later.

I don't have strong opinion there. We can always add them in a separate PR

[Geens]

Thanks for the input! I removed opamp6 from the stm32g471.

@dotcypress I think this pull request is ready for review.

[dotcypress]

LGTM 👍

[dotcypress]

Thank you @Geens and @pawelchcki