Re: [ECOS] MBX redboot

[Jesper Skov <jskov@cambridge.redhat.com>]

>>>>> "Jonathan" == Jonathan Larmour <jlarmour@redhat.com> writes:

>> "Natarajan, Mekala (CTS)" wrote:
>> 
>> How to debug the rom monitor(redboot).  When i build the redboot
>> image from the configuration tool, it creates *.elf, *.srec and
>> .bin file.  Can i use the .elf file,load this into ram and debug
>> the code(redboot).

Jonathan> No you can't debug redboot itself very easily because even a
Jonathan> RAM based RedBoot will steal most of the exception vectors
Jonathan> etc. for itself (as will any application that has GDB stubs
Jonathan> included). And quite right too - you wouldn't be able to use
Jonathan> a RAM based RedBoot to upgrade if it still relied on the
Jonathan> ROM/Flash based one to run.

Actually, debugging the vector magic can be done simply by changing
the location of the virtual vector table in the RAM application
(RedBoot).

Then the ROM monitor can be used for debugging most of the RAM app
startup initialization, including virtual vector setup. You may have
to hack a few things to prevent the RAM app from taking over exception
vectors and/or serial control. But it's definitely doable.

Jesper