On boot the VTOR (Vector Table offset register) is set to the start of .vectors
On boot .relocate is copied into .ramfunc and .data
On boot .bss is initiailized to all 0's.
All unitialized global variables are stored here.
On boot the stack is filled with 0xDEADBEEF, and the MSP (Master Stack Pointer) is set to the start of .stack.
All other RAM is unitialized and its contants random per reset. Unused Flash is marked as inaccessible.
The MPU (Memory Protection Unit) enforeces the permissions described in the Legend.