[ECOS] Questions about vectors.S (ARM port)

["llandre" <r&d at wawnet dot biz>]

I've just started to examine the vectors.S file.
Since I never worked before with GNU assembler, I would ask you some
explanations about it.

1) Where the symbols __rom_data_start is defined? I think it is generated by
the linker but I did not find it in the documentation of ld.

2) Which is the difference between the following instructions?
              ldr r1, =__exception_handlers
              ldr r1, .__exception_handlers
              ldr r1, __exception_handlers

3) Which is the meaning of the following macro?
#define  PTR(name)
.##name: .word name

4) The boot procedure assumes that the PLATFORM_SETUP1 macro performs
a remap operation in order to map RAM memory at the address 0.
If this operation is not possible (some microcontrollers don't permit to
modify
the base address of CS0), is it necessary to heavily change the vectors.S
file?


Thank you very much in advance.

llandre



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