stm32l0xx-hal VS awesome-embedded-rust

Once you can program the microcontroller with your toolchain (cargo, rustc, and cargo-embed or cargo-flash for programming), I would look at the stm32l0x3-hal repository example SPI code. There's also a more advanced example using DMA for data transfer instead of the blocking read and write calls.

Are you saying that this book is a hallucination? And this? And all of this?

Feel free to PR them to the awesome embedded rust list, and the matrix rooms for embedded rust and esp32 (linked on that page) are super active, so feel free to plug this there too :)

If you haven't already, feel free to PR it to the awesome embedded rust list!

list of curated rust microcontroller resources

embedded-hal trait-based HALs: There could be a better description than this. However, this category has the widest base of implementations with more options than can be mentioned here. A more comprehensive list can be found on the awesome embedded Rust repository.

For what it's worth, the ecosystem is definitely growing. See here: https://github.com/rust-embedded/awesome-embedded-rust, there are quite a few drivers for a pretty wide variety of sensors/periphs, and almost every large SoC line is supported.