ChibiOS/NIL
NIL has been created with the idea to bring RTOS functionalities to very small devices and yet to be a full-fledged RTOS.
In Brief
Tiny RTOS, below 1kB of code space in its maximum configuration.
Small size of memory objects like Thread, Semaphores etc.
Fully static architecture.
Regardless its size NIL is very efficient and supports a rich set of features.
RT vs NIL
Features comparison and use cases.
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