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The assembler supports several modifiers when using relocatable addresses in AVR instruction operands. The general syntax is the following:
modifier(relocatable-expression)
lo8
This modifier allows you to use bits 0 through 7 of
an address expression as 8 bit relocatable expression.
hi8
This modifier allows you to use bits 7 through 15 of an address expression
as 8 bit relocatable expression. This is useful with, for example, the
AVR ldi instruction and lo8 modifier.
For example
ldi r26, lo8(sym+10)
ldi r27, hi8(sym+10)
hh8
This modifier allows you to use bits 16 through 23 of
an address expression as 8 bit relocatable expression.
Also, can be useful for loading 32 bit constants.
hlo8
Synonym of hh8.
hhi8
This modifier allows you to use bits 24 through 31 of
an expression as 8 bit expression. This is useful with, for example, the
AVR ldi instruction and lo8, hi8, hlo8,
hhi8, modifier.
For example
ldi r26, lo8(285774925)
ldi r27, hi8(285774925)
ldi r28, hlo8(285774925)
ldi r29, hhi8(285774925)
; r29,r28,r27,r26 = 285774925
pm_lo8
This modifier allows you to use bits 0 through 7 of
an address expression as 8 bit relocatable expression.
This modifier useful for addressing data or code from
Flash/Program memory. The using of pm_lo8 similar
to lo8.
pm_hi8
This modifier allows you to use bits 8 through 15 of
an address expression as 8 bit relocatable expression.
This modifier useful for addressing data or code from
Flash/Program memory.
pm_hh8
This modifier allows you to use bits 15 through 23 of
an address expression as 8 bit relocatable expression.
This modifier useful for addressing data or code from
Flash/Program memory.
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