Re: [lwip-devel] memory alignment in 32bit architecture

[Piero 74]

you shoul be right..
i'm thinking to arm7 data abort can occur even for unaligned access,
but it could be possible to have only wrong data... anyway, in my
application i never try to recovery from exceptions, managing i prefer
to force a board restart.

i'd like to search a way to fix problem in lwip code

thanks for your reply
piero

2009/3/20, Sprow <address@hidden>:
> In article <address@hidden>,
>    Piero 74 <address@hidden> wrote:
>> my micro will generate a data abort exception.
>> what solution do you suggest?
>
> ARM7? I doubt it, the abort-on-unaligned-word-load option wasn't added to
> the ARM core until architechture 6, which the ARM7 isn't.
>
> Your memory controller might produce an abort, in which case you could write
> an exception handler to look at the aborting instruction, do a corresponding
> set of byte loads and shifts, store the result in the appropriate register
> then return from the abort.
>
> More simply you could look at the assembler output, if I remember IAR right
> it outputs correct code but warns you about too for good measure as it's
> often a mistake,
> Sprow.
>
>
>
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