Datasheet

20
2490R–AVR–02/2013
ATmega64(L)
The Indirect with Displacement mode reaches 63 address locations from the base address given
by the Y- or Z-register.
When using register indirect addressing modes with automatic pre-decrement and post-incre-
ment, the address registers X, Y, and Z are decremented or incremented.
The 32 general purpose working registers, 64 I/O Registers, 160 extended I/O Registers, and
the 4,096 bytes of internal data SRAM in the ATmega64 are all accessible through all these
addressing modes. The Register File is described in “General Purpose Register File” on page
13.
Figure 9. Data Memory Map
Memory Configuration B
32 Registers
64 I/O Registers
Internal SRAM
(4000 x 8)
$0000 - $001F
$0020 - $005F
$1000
$0FFF
$FFFF
$0060
Data Memory
External SRAM
(0 - 64K x 8)
Memory Configuration A
32 Registers
64 I/O Registers
Internal SRAM
(4096 x 8)
$0000 - $001F
$0020 - $005F
$1100
$10FF
$FFFF
$0060 - $00FF
Data Memory
External SRAM
(0 - 64K x 8)
160 Ext I/O Reg.
$0100