Re: [avr-gcc-list] extracting bytes

[Erik Christiansen]

On Fri, Dec 03, 2004 at 01:10:18AM -0800, Jonny Dyer wrote:
> In AVR-AS is there an assembler directive like HIGH() and LOW() in the 
> Atmel assembler for extracting bytes from a word?

Yes indeedy, there are two modifiers, used as follows:
hi8/lo8 treat the data or progmem label as a byte address, e.g. for use
with lpm. (So manual doubling, as in Atmel examples, is harmful.)
pm_hi8/pm_lo8 treat the progmem label as byte_address/2, e.g. for use
with icall.

e.g.:
ldi   ZL,pm_lo8(some_progmem_label)
ldi   ZH,pm_hi8(some_progmem_label)

Erik