Here[1] you will find the vector table of Cortex-M3 core.
There are 4 vectors (16 bytes) that are named "Reserved" (plus one more at index 13). Do you think they can be used for custom purposes? The word "Reserved" seems this can't be done.
I'd like to use those vectors, that are in the non-volatile Flash memory, to store some data. In my case, I will save the MAC address (6 bytes) and a product serial number (4 bytes).
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