Runtime (crt0)
By default, when using my link scripts, the standard runtime is initialised by crt0 as follows:
| Address | Size | Link Script Variable | Comment |
|---|---|---|---|
0x03fffe |
~256k | _STACK_SIZE |
Stack (SSP). Grows towards 0. At round about 0x0000400 it would start stomping all over the memory area used by the monitor |
0x040000 |
n/a | _RUN_ADDRESS |
Start of user program (.text), followed by initialised data (.data) and then unititialised data (.bss). The .bss area is initialised to all zeroes before main() is called. |
Heap
crt0 allocates all free memory from the end of the .bss area to the end of ram to the heap (malloc/free).