application-rs

Rust Example

As the other two examples in this Repo, this application implements a small abstraction of the runtimes API. The example program mentioned in the main README can be found in the examples folder.

This abstraction follows the API defined by embedded_hal. It by far doesn't cover every part of the API, but delivers a conform implementation for Gpios, serial connections and timers.

Building this example

This code gets compiled to the rust target wasm32-unknown-unknown. As the Rust compiler includes a huge stack in WASM, (see here), this code is compiled with the option -z stack-size=32768 (see config.toml). The library is seperated from the example, as they live in seperate folders (src and examples). The library tries to avoid any formatting code as this bloats the binary size in Rust. It is furthermore recommended to compile the program in release mode with the following profile:

[profile.release]
panic           = "abort" # aborts on panic, disabling most error formatting
codegen-units   = 1
opt-level       = 'z' # optimized for the size

The example avoids the formatting bloat by mapping all errors to the unit type () and returning in an error case. This can be more difficult to debug, but makes sure that the resulting binary is small.

To compile this example, execute the following command in this folder:

cargo b --release --example pins_and_gpio