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8210C–AVR–09/11
Atmel AVR XMEGA D
Figure 4-2.
Data memory map.
I/O memory, EEPROM, and SRAM will always have the same start addresses for all XMEGA
devices.
4.6
Internal SRAM
The internal SRAM always starts at hexadecimal address 0x2000. SRAM is accessed by the
CPU using the load (LD/LDS/LDD) and store (ST/STS/STD) instructions.
4.7
EEPROM
XMEGA AU devices ha EEPROM for nonvolatile data storage. It is addressable in a separate
data space (default) or memory mapped and accessed in normal data space. The EEPROM
supports both byte and page access. Memory mapped EEPROM allows highly efficient
EEPROM reading and EEPROM buffer loading. When doing this, EEPROM is accessible using
load and store instructions. Memory mapped EEPROM will always start at hexadecimal address
0x1000.
4.8
I/O Memory
The status and configuration registers for peripherals and modules, including the CPU, are
addressable through I/O memory locations. All I/O locations can be accessed by the load
(LD/LDS/LDD) and store (ST/STS/STD) instructions, which are used to transfer data between
the 32 registers in the register file and the I/O memory. The IN and OUT instructions can
address I/O memory locations in the range of 0x00 0x3F directly. In the address range 0x00 -
0x1F, single-cycle instructions for manipulation and checking of individual bits are available.
Start/End
Address
I/O Memory
(Up to 4 KB)
EEPROM
(Up to 4 KB)
Internal SRAM
0x0000
0x1000
0xFFFF
0x2000
Data Memory