And if the macro versions are employed a few times then they would quickly
grow larger than the table anyways.
--
Lucas Vinicius Hartmann

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Em qua., 29 de jul. de 2020 às 10:41, Gregory Nutt <spudan...@gmail.com>
escreveu:

>
> > What about platforms like AVR?  That would not be a good decision for
> > AVR since it is a harvard machine and cannot access data in ROM
> > without special operations.
>
> This is not a show stopper, at least not for the AVR.  While a
> table-driven solution is not optimal for AVR, it will support access to
> constant data in ROM if the data has the storage class IOBJ as defined
> in include/nuttx/compiler.h.  I don't know if the compiler will
> automatically generate the correct instruction to access the table
> across the bus bridge; I am not an AVR expert. There is a up_ function
> may need to be used to access the ROM table???
>
> AVR Memory:  https://microchipdeveloper.com/8avr:memory
> C Interface:
>
> http://ww1.microchip.com/downloads/en/AppNotes/Atmel-2575-C-Functions-for-Reading-and-Writing-to-Flash-Memory_ApplicationNote_AVR106.pdf
>
> Hmm.. I notice that compiler.h defines IOBJ as __flash but the above
> document says:  "The datatypes are actually used as __flashor
> __farflashpointers (consequently 16 and 24 bit)."  That should be change
> to __farflash.
>
>

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