The basic gist is that you fork mbed-os, add a package.json (see old C:\Users\<user>\.platformio\packages\framework-mbed file and adapt version) and add the platformio folder (builder scripts, GitHub - platformio/builder-framework-mbed: ARM mbed build script for PlatformIO Build System). You can then reference that fork as the source for framework-mbed through platform_packages.
Since the mbed-os version is above what the builder scripts expect, you may occassionally run into errors. I did when I just tested this using my fork and platformio.ini
[env:nucleo_f103rb]
platform = ststm32
board = nucleo_f103rb
framework = mbed
platform_packages =
framework-mbed@https://github.com/maxgerhardt/mbed-os.git
monitor_speed = 9600
and src\main.cpp and mbed_app.json from platform-ststm32/examples/mbed-rtos-blink-baremetal at develop · platformio/platform-ststm32 · GitHub
with the error
ModuleNotFoundError: No module named ‘jsonschema’:
A missing Python dependency. So I opened a CLI, used pio system info to find the Python executable and then executed
<python path> -m pip install jsonschema
to install the missing dependency.
After that, a “Upload & Monitor” gives
PACKAGES:
- framework-mbed 6.601500.210922+sha.d3c2a6db
- tool-dfuutil 1.9.200310
- tool-openocd 2.1100.0 (11.0)
- tool-stm32duino 1.0.2
- toolchain-gccarmnoneeabi 1.90201.191206 (9.2.1)
Collecting mbed sources...
..
--- Miniterm on COM3 9600,8,N,1 ---
--- Quit: Ctrl+C | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H ---
This is the bare metal blinky example running on Mbed OS 6.15.0.
--- exit ---
So this is running mbed-os 6.15.0 now, compared to the latest framework-mbed 6.9.0 package available.