Re: [avr-gcc-list] Pgmspace.h Use

[E. Weddington]

address@hidden wrote:

> Hello,
>
> for code portability reasons, I would like to avoid to call explicity the
> function pgm_read_byte() like in the following example :
>
> const prog_char array[7] = {0x10,0x20,0x30,0x40,0x50,0x60,0x70};
> y = pgm_read_byte(&array[2]);
> // I would like to to keep the syntax y = array[2]; without having the array
> copied in the SRAM
>
> Is there a way to do it ?
>
>  
No. The declaration you give above *is* how you put the array in Flash,
and how you access the array in Flash. GCC requires a new feature patch
for it to know that the expression, y = array[2], means that array is in
Flash and to use the correct assembly sequence. There is a person
working on such a feature, however, it is very non-trivial to implement
in GCC. And currently there is not a deadline when this work will be
completed as it being written by a volunteer.

Eric Weddington