Modern embedded framework, using Rust and async.
Find a file
2022-04-13 16:04:31 -04:00
.github Update cargo-batch. 2022-04-08 00:35:00 +02:00
.vscode embassy, embassy-nrf: add nightly Cargo feature to gate nightly-only features. 2022-02-12 01:16:31 +01:00
docs Update after review 2022-02-23 13:24:09 +01:00
embassy Merge #694 2022-04-12 21:27:13 +00:00
embassy-boot Avoid writing bootloader flash if not needed 2022-03-31 15:23:06 +02:00
embassy-hal-common Update rust nightly, embedded-hal 1.0, embedded-hal-async. 2022-03-11 00:38:07 +01:00
embassy-lora Update to latest rust-lorawan version 2022-04-08 12:58:57 +02:00
embassy-macros macros: cleanup, make work in stable. 2022-02-12 01:16:31 +01:00
embassy-net Add more docserver metadata. 2022-04-05 21:05:09 +02:00
embassy-nrf Make Driver::disable async and fix comment 2022-04-13 14:55:02 -04:00
embassy-rp Reexport unborrow macro in HALs 2022-04-07 12:57:02 +02:00
embassy-stm32 Merge #714 2022-04-12 21:42:36 +00:00
embassy-traits Update rust nightly, embedded-hal 1.0, embedded-hal-async. 2022-03-11 00:38:07 +01:00
embassy-usb Split UsbDevice::run into run and run_until_suspend 2022-04-13 16:04:31 -04:00
embassy-usb-hid Remove channel and make run future cancelable 2022-04-13 14:55:02 -04:00
embassy-usb-serial Remove channel and make run future cancelable 2022-04-13 14:55:02 -04:00
examples Split UsbDevice::run into run and run_until_suspend 2022-04-13 16:04:31 -04:00
stm32-data@8fb98d7462 Add ADC support for H7 2022-04-12 22:25:00 +02:00
stm32-gen-features Add stm32wlexx support 2022-04-08 03:43:58 +02:00
stm32-metapac Convert chip name to upper case to fix rebuilds 2022-03-28 18:44:17 +03:00
stm32-metapac-gen Merge #668 2022-03-15 22:19:59 +00:00
tests/stm32 stm32/spi: fix blocking transfer hanging after async. 2022-03-15 04:13:33 +01:00
xtask Update lots of deps 2021-09-11 01:35:23 +02:00
.gitignore ci: add build with stable. 2022-02-12 01:16:31 +01:00
.gitmodules Add stm32-metapac crate, with codegen in rust 2021-05-31 02:40:58 +02:00
ci.sh Add stm32wlexx support 2022-04-08 03:43:58 +02:00
ci_stable.sh Add STM32F217ZG to CI 2022-03-27 19:56:44 +03:00
LICENSE-APACHE First commit 2020-09-22 18:03:43 +02:00
LICENSE-MIT First commit 2020-09-22 18:03:43 +02:00
README.md traits: migrate Delay to embedded-hal 1.0+async, remove Rng and Flash. 2022-01-27 00:08:02 +01:00
rust-toolchain.toml Update rust nightly, embedded-hal 1.0, embedded-hal-async. 2022-03-11 00:38:07 +01:00

Embassy

Embassy is a project to make async/await a first-class option for embedded development. For more information and instructions to get started, go to https://embassy.dev.

Executor

The embassy::executor module provides an async/await executor designed for embedded usage.

  • No alloc, no heap needed. Task futures are statically allocated.
  • No "fixed capacity" data structures, executor works with 1 or 1000 tasks without needing config/tuning.
  • Integrated timer queue: sleeping is easy, just do Timer::after(Duration::from_secs(1)).await;.
  • No busy-loop polling: CPU sleeps when there's no work to do, using interrupts or WFE/SEV.
  • Efficient polling: a wake will only poll the woken task, not all of them.
  • Fair: a task can't monopolize CPU time even if it's constantly being woken. All other tasks get a chance to run before a given task gets polled for the second time.
  • Creating multiple executor instances is supported, to run tasks with multiple priority levels. This allows higher-priority tasks to preempt lower-priority tasks.

Utils

embassy::util contains some lightweight async/await utilities, mainly helpful for async driver development (signaling a task that an interrupt has occured, for example).

HALs

Hardware Absraction Layers with asynchronous behaviors are provided for a variety of platforms. For example, the embassy-nrf crate contains implementations for nRF 52 series SoCs.

  • uarte: UARTE driver implementing AsyncBufRead and AsyncWrite.

  • qspi: QSPI driver implementing Flash.

  • gpiote: GPIOTE driver. Allows awaiting GPIO pin changes. Great for reading buttons or receiving interrupts from external chips.

  • saadc: SAADC driver. Provides a full implementation of the one-shot sampling for analog channels.

  • rtc: RTC driver implementing Clock and Alarm, for use with embassy::executor.

Examples

Examples are found in the examples/ folder seperated by the chip manufacturer they are designed to run on. For example:

  • examples/nrf are designed to run on the nrf52840-dk board (PCA10056) but should be easily adaptable to other nRF52 chips and boards.
  • examples/rp are for the RP2040 chip.
  • examples/stm32 are designed for the STM32F429ZI chip but should be easily adaptable to other STM32F4xx chips.
  • examples/std are designed to run locally on your pc.

Running examples

  • Setup git submodules (needed for STM32 examples)
git submodule init
git submodule update
  • Install probe-run with defmt support.
cargo install probe-run
  • Change directory to the sample's base directory. For example:
cd examples/nrf
  • Run the example

For example:

cargo run --bin blinky

Developing Embassy with Rust Analyzer based editors

The Rust Analyzer is used by Visual Studio Code and others. Given the multiple targets that Embassy serves, there is no Cargo workspace file. Instead, the Rust Analyzer must be told of the target project to work with. In the case of Visual Studio Code, please refer to the .vscode/settings.json file's rust-analyzer.linkedProjectssetting.

Minimum supported Rust version (MSRV)

Required nightly version is specified in the rust-toolchain.toml file. Nightly is required for:

  • generic_associated_types: for trait funcs returning futures.
  • type_alias_impl_trait: for trait funcs returning futures implemented with async{} blocks, and for static-executor.

Stable support is a non-goal until these features get stabilized.

Documentation

Embassy documentation is located in the docs/ folder. The documentation is built in embassy-book and published to https://embassy.dev by CI.

Why the name?

EMBedded ASYnc! :)

License

This work is licensed under either of

at your option.