[Bug target/20288] AVR assignment of a value through a 16 bit pointer generates out of order code

["schlie at comcast dot net" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From schlie at comcast dot net  2005-03-02 23:07 -------
(In reply to comment #0)
> [The follow emphasis is Atmel's from the data-sheet]:
> 
> "On the AVR to do a 16-bit write, *THE HIGH BYTE MUST BE WRITTEN BEFORE THE LOW
> BYTE*. For a 16-bit read, THE LOW BYTE MUST BE READ BEFORE THE HIGH BYTE."
> 
> This applies to all internal 16 bit I/O registers.

Personally see no problem.  The quote above has specifically to do with how to write a
logical 16-bit timer/counter value into a pair of otherwise distinct 8-bit registers, which
controls a specific peripheral function which presumes a specific write sequence to maintain
the logical integrety of that specific timer/counter value; it has nothing to with 16-bit pointers,
the sequencing of multi-byte logical data type transactions, or the compiler in general.



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20288