FreeRTOS

A version is available now for the Ras Pi Pico.

See: https://www.freertos.org/Documentation/02-Kernel/03-Supported-devices/04-Demos/Raspberry-Pi/smp-demos-for-the-raspberry-pi-pico-board
Says it was updated Nov 2024, but the repo it points to clearly says it's depreciated and points to another repo. None of them really explain correctly how to download the actual RTOS.

Corrected(ish) notes:

# https://datasheets.raspberrypi.org/pico/getting-started-with-pico.pdf
# install VSCode, and the Raspberry Pi Pico extension, in the extension
# "Open New Project From Example" and select the blink, then set the location to
# a new PiPico folder under Documents. 
# You must build the project to get the SDK downloaded
cd ~/Downloads
# https://github.com/FreeRTOS/FreeRTOS
git clone https://github.com/FreeRTOS/FreeRTOS.git --recurse-submodules
cd FreeRTOS
git submodule update --init --recursive
export PICO_SDK_PATH=~/.pico-sdk/sdk/2.1.0 #or whatever version it is
export PICO_TOOLCHAIN_PATH=~/.pico-sdk/toolchain/13_3_Rel1
export FREERTOS_KERNEL_PATH=~/Downloads/FreeRTOS/FreeRTOS/Source
# https://github.com/FreeRTOS/FreeRTOS-Community-Supported-Demos
# download the zip and extract. 
cd ~/Downloads/FreeRTOS/FreeRTOS-Community-Supported-Demos-main/CORTEX_M0+_RP2040
mkdir build
cd build
cmake ..
make

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