as: AVR-Modifiers
1
1 9.5.2.3 Relocatable Expression Modifiers
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1
1 The assembler supports several modifiers when using relocatable
1 addresses in AVR instruction operands. The general syntax is the
1 following:
1
1 modifier(relocatable-expression)
1
1 'lo8'
1
1 This modifier allows you to use bits 0 through 7 of an address
1 expression as 8 bit relocatable expression.
1
1 'hi8'
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1 This modifier allows you to use bits 7 through 15 of an address
1 expression as 8 bit relocatable expression. This is useful with,
1 for example, the AVR 'ldi' instruction and 'lo8' modifier.
1
1 For example
1
1 ldi r26, lo8(sym+10)
1 ldi r27, hi8(sym+10)
1
1 'hh8'
1
1 This modifier allows you to use bits 16 through 23 of an address
1 expression as 8 bit relocatable expression. Also, can be useful
1 for loading 32 bit constants.
1
1 'hlo8'
1
1 Synonym of 'hh8'.
1
1 'hhi8'
1
1 This modifier allows you to use bits 24 through 31 of an expression
1 as 8 bit expression. This is useful with, for example, the AVR
1 'ldi' instruction and 'lo8', 'hi8', 'hlo8', 'hhi8', modifier.
1
1 For example
1
1 ldi r26, lo8(285774925)
1 ldi r27, hi8(285774925)
1 ldi r28, hlo8(285774925)
1 ldi r29, hhi8(285774925)
1 ; r29,r28,r27,r26 = 285774925
1
1 'pm_lo8'
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1 This modifier allows you to use bits 0 through 7 of an address
1 expression as 8 bit relocatable expression. This modifier useful
1 for addressing data or code from Flash/Program memory. The using
1 of 'pm_lo8' similar to 'lo8'.
1
1 'pm_hi8'
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1 This modifier allows you to use bits 8 through 15 of an address
1 expression as 8 bit relocatable expression. This modifier useful
1 for addressing data or code from Flash/Program memory.
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1 'pm_hh8'
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1 This modifier allows you to use bits 15 through 23 of an address
1 expression as 8 bit relocatable expression. This modifier useful
1 for addressing data or code from Flash/Program memory.
1