ESP32 Hello World Example (with defmt)

Setup

• Rust =1.77 : The rustup command to install toolchains. (link)
• espup : The ESP32 toolchain installation (link)

This crate compiles for no_std environments.

Compile

$ rustup run esp cargo build --release;

Problem

In the Cargo.toml, if the patch.crates-io is :

• not commented : it compiles with the commands above

• commented : it does not compile with the following error :

  --> /home/ferris/.cargo/registry/src/index.crates.io-6f17d22bba15001f/embedded-hal-1.0.0/src/lib.rs:21:5
  |
  21 | use defmt as defmt;
  |     ^^^^^^^^^^^^^^ no external crate `defmt`
  
  For more information about this error, try `rustc --explain E0432`.
  error: could not compile `embedded-hal` (lib) due to 1 previous error
  warning: build failed, waiting for other jobs to finish...