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Re: [avr-libc-dev] missing pgm_read_ptr


From: Joerg Wunsch
Subject: Re: [avr-libc-dev] missing pgm_read_ptr
Date: Tue, 7 Jul 2015 08:44:47 +0200
User-agent: Mutt/1.5.23 (2014-03-12)

As Maurin Donneaud wrote:

> I have linux avr-libc 1:1.8.0-4.1 installed
> I'm wondering why pgmspace.h do not have the pgm_read_byte macro ?

$ fgrep pgm_read_byte ~/src/avr-libc/include/avr/pgmspace.h
    pgm_read_byte_near() or pgm_read_word_near() instead of
    pgm_read_byte_far() or pgm_read_word_far() since it is more efficient that
    \def pgm_read_byte_near(address_short)
#define pgm_read_byte_near(address_short) __LPM((uint16_t)(address_short))
    \def pgm_read_byte_far(address_long)
#define pgm_read_byte_far(address_long)  __ELPM((uint32_t)(address_long))
    \def pgm_read_byte(address_short)
#define pgm_read_byte(address_short)    pgm_read_byte_near(address_short)

So well, I think it's just there.
-- 
cheers, Joerg               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/
Never trust an operating system you don't have sources for. ;-)



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