Re: String array in ROM gives error in spite of following example code.
Royce Pereira <[email protected]>
| Newsgroups | gmane.comp.hardware.avr.gcc |
|---|---|
| Message-ID | <CACzHkniJzAQuiXcJ=ukF61izpG8y2uoA2eRW73Fknrq8Mvmjdg@mail.gmail.com> |
Thank you, all, for the guidance. On Fri, Jun 13, 2014 at 12:44 PM, Senthil Kumar Selvaraj <[email protected]> wrote: > On Fri, Jun 13, 2014 at 12:02:58PM +0530, Royce Pereira wrote: >> Thanks, Joerg, >> >> This is news to me :) ! >> >> I googled for '__flash qualifier in AVR-GCC' and I understand that >> using __flash eliminates the need for 'pgm_read_byte(&flashLocation)' >> ? > > It reads as many bytes as necessary. >> >> That is, you read it directly (like other ram variables), and avr gcc >> will read it from flash automatically ? >> > > Yes. And there's the __memx qualifier which lets you access both flash > and RAM seamlessly. > > If you use the __flash<n> qualifiers to place data in flash, there's some > linker script setup involved. > > Regards > Senthil >> >> On Fri, Jun 13, 2014 at 11:19 AM, Joerg Wunsch <[email protected]> wrote: >> > Royce Pereira <[email protected]> wrote: >> > >> >> Even the libc documentation, which was once the bible of avr-gcc on >> >> this is not accurate. The sample code just does not work. >> > >> > Apparently, nobody noticed before. Please, file a bug report >> > to the avr-libc project, so we can fix that. >> > >> > The question here (as always) is whether you really want both, the >> > strings itself as well as the pointers (table of it) in flash. The >> > table is quite small, and could as well be kept in RAM unless you are >> > very thight on RAM. >> > >> > As the compiler now understands the __flash qualifier, using that >> > would make it a lot easier. >> > -- >> > cheers, Joerg .-.-. --... ...-- -.. . DL8DTL >> > >> > http://www.sax.de/~joerg/ >> > Never trust an operating system you don't have sources for. ;-) >> > >> > _______________________________________________ >> > AVR-GCC-list mailing list >> > [email protected] >> > https://lists.nongnu.org/mailman/listinfo/avr-gcc-list >> >> >> >> -- >> Best Regards, >> >> -- Royce Pereira >> >> _______________________________________________ >> AVR-GCC-list mailing list >> [email protected] >> https://lists.nongnu.org/mailman/listinfo/avr-gcc-list -- Best Regards, -- Royce Pereira