Re: [avr-gcc-list] How to convert Flash Strings from IAR to GCC?

[E . Weddington]

> 
> I'm trying to convert some code from IAR 2.28 to GCC , 
but I can't get
> the GCC version to read strings from flash, the way that 
IAR does.
> 
> I've read the FAQ on getting string in Flash, and the 
recent thread on
> "Strings in Flash".
> 
> I know I could use pgm_read_byte_near() in the case I 
show here, but I 
> need to stay backwards compatible with IAR, 
unfortunately, and it appears in 
> several different places that one I show here.
> 
> How do I get GCC to generate functions that automatically 
uses LPM the way 
> IAR does?

You can't.
GCC does not automatically generate LPM the way that IAR 
does. That's why there are macros in avr-libc to generate 
the necessary assembly code to read data from Flash.

That's why it's necessary to use the pgm_read_* macros 
inside your flash_str_out function.

Eric