FreeRTOS-rust

This project is based on code from freertos.rs and some additions to simplify the usage of FreeRTOS in embedded applications written in Rust.

In contrast to freertos.rs this crate differs in these points:

• The application main() entry point is written in Rust.
• The FreeRTOS scheduler can be started from Rust.
• The FreeRTOS heap MemMang/heap/heap_x.cis used as global memory allocator for Rust
• No need for a Clang skeleton project

How it works

The freertos-cargo-build build-dependency compiles the FreeRTOS code from its original "C" sources files into an archive to be linked against your Rust app. Internally it uses the cc crate and some meta info provided by your apps build.rs:

1. A path to the FreeRTOS Sources
2. A path to the app specific FreeRTOSConfig.h
3. A relative path to the FreeRTOS port to be used, e.g. for ARM Cortex-M3 cores.
4. Optional: Additional C code to be compiled

The freertos-rust dependency provides an interface to access all FreeRTOS functionality from your (embedded) Rust app.

Usage

1. Checkout FreeRTOS: https://github.com/FreeRTOS/FreeRTOS-Kernel

2. Add dependencies to your Rust apps Cargo.toml

   [dependencies]
   freertos-rust = "*"
   
   [build-dependencies]
   freertos-cargo-build = "*"
   

3. Add this snippet to your apps build.rs:

   fn main() {
       let mut b = freertos_cargo_build::Builder::new();
   
       // Path to FreeRTOS kernel or set ENV "FREERTOS_SRC" instead
       b.freertos("path/to/FreeRTOS-Kernel");
       b.freertos_config("src");       // Location of `FreeRTOSConfig.h` 
       b.freertos_port("GCC/ARM_CM3"); // Port dir relativ to 'FreeRTOS-Kernel/portable' 
       b.heap("heap4.c");              // Set the heap_?.c allocator to use from 
                                       // 'FreeRTOS-Kernel/portable/MemMang' (Default: heap_4.c)       
   
       // b.get_cc().file("More.c");   // Optional additional C-Code to be compiled
   
       b.compile().unwrap_or_else(|e| { panic!(e.to_string()) });
   }
   

Used C compiler

freertos-cargo-build depends on the cc crate. So the C compiler used can be set by using the CC enviroment variable or otherwise defined by internal defaults. For the ARM architecture this is the arm-none-eabi-gcc which can be found here.

Examples

To get started there are examples in freertos-rust-examples for:

• Cortex M33 (nRF9160)
• Cortex M3 (STM32L151CBU6A)
• Cortex M4 (STM32F411CEU6)
• Windows
• ...more to come...

Project Crates

• To build a project using this create see freertos-cargo-build
• The runtime dependency for you FreeRTOS Rust application will be freertos-rust

License

This repository is using the MIT License. Some parts might state different licenses that need to be respected when used.

• The Linux port is licensed under GPLv2