Zephyr and the Memory Footprint

Do you want to use Zephyr RTOS on a Microcontroller with only a few bytes of Flash? Let's try it!

On the Optimizing for Footprint doc site you will find some hints how to reduce the memory footprint. With this I could reduce the kernel to 6872 bytes. Ok, this is just the kernel to have an idea how much flash it needs. You can analyze the memory usage from the rom/ram-report (for more details have a look at the Zephyr Optimization Tools).

Memory region         Used Size  Region Size  %age Used
           FLASH:        6872 B        16 KB     41.94%
            SRAM:        1232 B         2 KB     60.16%
        IDT_LIST:          56 B         2 KB      2.73%

But how much does a small hello world application need, for example?