2 releases

0.1.1 Mar 24, 2024
0.1.0 Mar 21, 2024

#431 in Hardware support

Download history 281/week @ 2024-03-20 35/week @ 2024-03-27 30/week @ 2024-04-03

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1.5K SLoC


JABI (Just Another Bridge Interface) makes creating and deploying bridge devices that provide RPC to common microcontroller peripherals simple.


Interfaces are the available methods by which a single client may connect. Multiple interfaces running concurrently is supported. The following interfaces are currently supported.

  • USB
  • UART

Microcontroller peripherals are made available over each interface via a custom basic RPC. Each interface listens for request packets and dispatches them to the appropriate peripheral. Multiple instances of each peripheral type is supported. The following peripherals are currently supported.

  • Metadata
  • CAN (FD)
  • LIN
  • SPI controller
  • I2C controller
  • UART
  • GPIO
  • PWM
  • ADC
  • DAC

Clients connect to the microcontroller over any one of the interfaces. The following clients are supported.

  • C++
  • Python - pip install pyjabi
  • gRPC
  • Rust - cargo add jabi



Follow Zephyr's Getting Started Guide to get dependencies installed. Then create a new workspace using this repo. We'll create it under jabi, but you can use whatever you want.

west init -m https://github.com/dragonlock2/JABI.git jabi
cd jabi && west update

To port any board, you'll need the following. See firmware/boards for examples.

  • Zephyr board definition. See Zephyr's Board Porting Guide for help.
  • firmware/boards/<board>.conf - enable device drivers and any desired settings
  • firmware/boards/<board>.overlay - selects available interfaces and peripherals

Now compile and flash the firmware.

west build -b <board>
west flash


If you want to build from source, you may need to install a few dependencies.

  • macOS
    • brew install git cmake autoconf automake libtool libusb grpc openssl
  • Linux
    • apt install git cmake autotools-dev autoconf libtool libusb-1.0-0-dev libssl-dev
    • Install grpc from source.
  • Windows
  • Windows (MSYS2/MinGW) (experimental)
    • Install MSYS2 to install the following packages.
    • pacman -S mingw-w64-ucrt-x86_64-gcc git mingw-w64-ucrt-x86_64-cmake mingw-w64-ucrt-x86_64-autotools mingw-w64-ucrt-x86_64-libusb mingw-w64-ucrt-x86_64-grpc
      • If you're not on x86_64, your exact package names may be different.


C++ support is provided as a CMake library and can be added to any CMake project using add_subdirectory. An example project is in examples/cpp.


A Python library is published on PyPI. For the latest changes, it can be built and installed locally by running the following. An example using it is in examples/python.

pip install clients/python


Protobuf definitions are located in jabi.proto. grpc-server is a reference server implementation that bridges one device to a network and can handle parallel requests. It provides various arguments for selecting the desired device. An example client is in examples/grpc-client.


A Rust crate is published on crates.io. For the latest changes, it can be added locally. An example project is in examples/rust.


The following gRPC clients.

  • Google Flutter cross-platform app

Fun things to look into one day.

  • Better documentation...
  • Unit testing...
  • Alternative functions for pins
  • Move to Thrift for RPC (natively supported in Zephyr!)
    • Network (Ethernet, WiFi) support
  • BLE support
  • USB Linux drivers to show up under /dev
  • USB HS dev board for comparable performance to STLINK-V3


~101K SLoC