So when writing the Rust code, you used primitive Rust types. I know in the standard library there is the std::ffi C types that are redefined for Rust, but I understand here in the embedded space having the whole std library is overkill or not possible. My question is though, are there circumstances where the Rust types and C types don’t match in the function signature and the function either fails or causes undefined behavior? If so, would you happen to know any methods by which to avoid this behavior? Thanks for the great video!

This is going to be very useful as I have a C project that I would love to add some Rust code into. Thank you for showing me the way.

the edition in rust is actually the Rust major version, it basically the year it was released in, but its not the year you made your project in.

you can actually pass the '--lib' flag to cargo new to make a library from the start

Maybe to go further, you could create a library target in the CmakeLists file with perhaps a custom build command to build the whole binary all in one go with the use of a single make command.

1:55 actually 'edition = "2021"' refers to the RUST VERSION. Has nothing to do with the date you made your project

This is extremely cool. Can't pretend to completely understand it, but the ability to use C libraries could be super-useful in future. Thank you!

Did you explain why you have the rust signatures for gpio_put_explicit and sleep_ms with return type i32, even though the actual C functions both return void?

I wish cmake would let you just add rust as a lang for the project, and then your rust and C code 'just work' together like C and C++. I know there are reasons that make this unrealistic but its really the dream for me to be able to seriously mix it all together

if you want rust and C to work together easier then make it compile to a obj file and link that to C meaning when compiling then no having to link a library just link both obj files

This is excellent work. Clear, concise, thorough.

Well, that's convenient. I began a project with C-Rust interop a few hours ago.

The "edition" key *does not mean* year created. Rust editions are are not released every year, and it defines a set of things you want that may contain breaking changes (such as the standard library). This allows those core components to be updated and have breaking changes without breaking old projects when they update rust, as they still use the old edition. The default edition is always the most recent edition, in this case 2021(however we may be getting edition 2024 later this year)

I just wanted to thank you for your channel, and the wonderful work you do. Specially the rust embedded

This is great, thanks! My current goals include learning C and Rust, so this video is perfect for me.

Your channel is a gold mine.

Rust has just made it into the linux kernel. Proof that these two languages can live in peace

Panik with a k is just panic in german :D

Great video! I am now on my way to Micro Center to buy a Pi Pico!

in the first part of the video you did `cmake .`, it's better to keep generated files in a build folder so ``` mkdir build cd build cmake .. ``` that way you can (if you want a clean build) just delete the build folder and create a new one, also if your using git you can add `build` to the .gitignore file so that the build files don't get tracked

That's a cool demo, I'm interested in rust but I've never tried it before, it's an interesting use case ! Just une question, you "lied to the compiler" with the return values, why ? Is it like in maths "when it's too complex for the moment, so we're gonna ignore it" ?

To add here, to help with the CMake import of the library, one could use "corrosion-rs/corrosion".

How do you validate that the ‘bool’ on the C side is the same bit-size as the ‘bool’ on the Rust side? Also how do you validate that the ‘int’ on the C side is the same bit-size as the ‘i32’ on the Rust side? IIRC, I remember that it may cause problems, ‘int’ in C may be 32 bits wide but it doesn’t have to, The same thing about the ‘bool’ type variable, Some languages use an 8 bit integer to represent it while others use a 32 bit integer to represent it, How do you validate that the types on both the C and Rust side align with each other? Thanks.

I maybe missed it, but when do you import the c library into rust? Or how does rust know where those two c functions are?

Really awesome video!

You are using terminal impressively fast! How did you figure out the shortcuts?

Really cool video! I was left with a couple of doubts, In the video you declare functions that receive/return integers or booleans, which are variables that both C and Rust understand, what if you want to send a Rust reference or C pointer? Or a struct declared on C or Rust? And is it possible to run C code alongside Rust using the embassy framework?

Can we use only rust without C for embedded development? Or is there a library which handles all of these FFI things?

Another great vid 👍

9:33 I'm curious why you're "lying" to the compiler about the return value. Is it for demo purposes, are you unable to omit the return value, or are you unable to specify `-> ()`?

Great video!

My challenge is managing interrupts between two cores where one runs C and the other runs Rust.

I love C++ but I don't think that C++ and C really are competing today. I believe C++ and Rust are languages that are suitable for application software like compilers or system utilities. However for system software I think languages like Odin, V, Zig and most notably Mojo will be contenders to dethrone C in embedded, system and low-level software. Personally I think this language X is better than language Y is a bit of a flawed perspective as all languages have their pros and cons.

Any languages can coexist peacefully. It's the people using them can't.

y do you use sublime instead of nvim?

Does Rust on the pico have working concurrency? Does Rust work with the memory compactor/defragmenter on FreeRTOS? Edit:Seems like there is a rust crate for interfacing with FreeRTOS.

Hey, would you do a video on the SSD1306 display? how to correctly address page in all modes, horizontal, vertical and page addressing mode, To be able set cursor anywhere to want it. the pages/column thing is easy to understand, basically the stuff from page 28 to 32. you're able to send a single one of multiplier bytes, 2 modules in command and 2 modes for data. the order how bytes are send. the datasheet is kinda hard to understand, more people complain about it. i have seen 2 approaches on how people handle the I²C stuff, but only one of them is how it actually works, the other one an indirect and abstract method, but works. i use a original Microchip Fubarino pic32mx and the Arduino IDE, but not using the arduinio library language of what ever it's called, like you would program a pic and manipulate it's registers directly.

C Never Dies, U Can add C to Rust, But You can't Add Rust to C.

yoo finally

Is it possible to have this the other way round? I.e. have the Rust as the library and not the C.

Please as next step show us debugging this code.

Rust and Soylent Green are our future!

Since they both use LLVM, could you link them at the object level and forgo making them as a library? Assuming names and types match up. I think I'm missing something important here...

Yeah but then there is no point in using rust. It's still cool knowledge to have I guess but it does defeat the point of using rust.

This would also work with C++, right?

Can we write C to the Pico from Nano?

2021 is the version of rust release

the edition is the rust's edition, not the project's edition Its not really obvious

edition has nothing to do with your project its the version of rust you run on

What is this war?

C+Rust = CRust

Crust

Neat

This was hard to follow, too many aspects went unexplained.

CRust.

You're writing rust as a C programmer, how dear you?:D

:O

No they can't :). Because the compiler can't no the memory state of data that has gone through C... So even if all your Rust code is safe, C taints it.