Re: [ECOS] MIPS Evalution board boot ROM

[Jonathan Larmour <jlarmour at redhat dot co dot uk>]

Bart Veer wrote:
> 
> >>>>> "Ling" == Ling Su <lingsu@palmmicro.com> writes:
> 
>     Ling> I remembered that I have to burn a CygMon ROM to debug eCos
>     Ling> on the MIPS evaluation board. I just find the
>     Ling> /ecos/loaders/vr4300-4373/stubrom.bin and stubrom.img, is
>     Ling> that the CygMON mentioned before? Currently my board is
>     Ling> configured by a PMON boot ROM, if I replace it, how could I
>     Ling> find the manual for the CygMON, otherwise, I am not sure how
>     Ling> could I go ahead to try it.
> 
> What is needed on the target hardware is something that implements the
> gdb target-side stubs, so that gdb is able to interact sensibly with
> the target board. gdb is able to interact with some other rom monitors
> but quite possibly at reduced functionality, for example there will be
> no thread-aware debugging. Offhand I do not know how well gdb can
> interact with pmon.

It can't. If you have PMON on the board, and you want your application to
work under that, you can set the CYGSEM_HAL_USE_ROM_MONITOR option ("Work
with a ROM monitor") to PMON rather than "GDB_stubs", which should allow
programs to be loaded under PMON. However you can't debug them with GDB
which makes development more than a little difficult!

> To avoid incompatibility problems between gdb and
> the target side code, we recommend installing target-side gdb stubs.
> This can be a full-blown cygmon rom monitor, or it can be just a
> minimal set of stubs. If you only intend to use gdb then there is no
> reason to prefer cygmon over just the stubs.

[ As mentioned in my other mail, cygmon is not supported for the vrc4373 ]
 
[snip useful docs]

Jifl
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