This repository houses example applications built for the Arm® Mbed™ OS platform that demonstrate the usage and abilities of the Bluetooth® Low Energy (BLE) firmware-over-the air (FOTA) service. The service specification and sources can be found here. As defined in the specification, the FOTA service facilitates the transfer of firmware updates over BLE.
The examples come with batteries included! They're bundled with an automated build tool, "fota.sh", that eases the build process for the end-user. Please refer to the sections below for more information.
Currently, the only supported target boards for the examples are the NRF52840_DK and DISCO_L475VG_IOT01A. The BLE documentation describes the BLE APIs available on Mbed™ OS; going through this documentation isn't strictly essential to run the examples, but is helpful in understanding the sources.
The fota.sh cli tool aids in setup and build of the examples in this repository. Please run ./scripts/fota.sh --help for usage instructions.
Note: If the
-for--flashoption isn't provided (it could be the case that an end-user is trying to build without the board connected), then the target binary is not flashed. This is especially useful for building the examples with a CI workflow. Note that both flashing and erasing is acheived usingpyocd.In the case of the MCUboot example, the "factory firmware" is saved and would require manual transfer when the board is indeed connected. In either case, the demonstration step would be the only part that requires manual intervention from the user.
Important: The tool assumes the target board (
NRF52840_DK), toolchain (GCC_ARM), and example (mock) unless otherwise specified by the end-user. Currently, only theGCC_ARMtoolchain has been verified to work; the verification of functionality for binaries built using ARM Compiler 6 is pending.
Please refer to the example-specific READMEs for build and demonstration instructions.
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Dependency Conflicts: The difference in version requirements of the PyYAML dependency imposed by both mbed-os and pyocd led to the creation of a temporary virtual environment (venv), which is used in the target binary flashing stage of both examples. This is a known issue and would require changes to the
requirements.txtfile in the mbed-os to resolve. Another conflict is that between pyocd and mbed-ls on the version requirement of PrettyTable, which is resolved through the temporary venv.
Yet another minor conflict that doesn't hinder the build process is one between mbed-tools and mbed-os on the version requirement of the Click dependency; mbed-tools requires that the minimum version of Click to be greater than 7.1 while mbed-os requires it to be greater than 7.0. Now, the dependencies for mbed-os are installed after those of mbed-tools, which overwrites the newer version and generates a conflict. This would (again) require changes to the requirements file in the mbed-os repository to bump up the minimum version number of Click to 7.1. -
Target Binary Flashing: For the Mock example, compiling with mbed-tools results in the following error:
ERROR: Build program file (firmware) not found <path to mock example>/target/cmake_build/<target board>/develop/<toolchain>/target.hexThe tool is looking for a hex file under the cmake build output whose name comes from project directory (in this case, "target"). However, the generated one is named
BLE_GattServer_FOTAService.hex. Again, this is a known issue and has been filed (282) in the mbed-tools repository by noonfom.
The software in this repository is licensed under Apache-2.0. Please refer to LICENSE for more information.
Mbed™ OS is an open-source, device software platform for the Internet of Things. Contributions are an important part of the platform, and our goal is to make it as simple as possible to become a contributor. Contributions to this repository are greatly appreciated and accepted under the same Apache-2.0 license. To encourage productive collaboration, as well as robust, consistent and maintainable code, we have a set of guidelines for contributing to Mbed™ OS.
Important: Please target the
developmentbranch of this repository for pull requests.